clean up unused imports

.drone.yml

@@ -25,12 +25,12 @@ steps:
   - name: unit-integration-tests
     image: maven:3-jdk-11
     environment:
-      VAULT_VERSION: 1.6.1
+      VAULT_VERSION: 1.7.0
     commands:
-      - curl -s -o vault_1.6.1_linux_amd64.zip https://releases.hashicorp.com/vault/1.6.1/vault_1.6.1_linux_amd64.zip
+      - curl -s -o vault_1.7.0_linux_amd64.zip https://releases.hashicorp.com/vault/1.7.0/vault_1.7.0_linux_amd64.zip
-      - curl -s https://releases.hashicorp.com/vault/1.6.1/vault_1.6.1_SHA256SUMS | grep linux_amd64 | sha256sum -c
+      - curl -s https://releases.hashicorp.com/vault/1.7.0/vault_1.7.0_SHA256SUMS | grep linux_amd64 | sha256sum -c
-      - unzip vault_1.6.1_linux_amd64.zip
+      - unzip vault_1.7.0_linux_amd64.zip
-      - rm vault_1.6.1_linux_amd64.zip
+      - rm vault_1.7.0_linux_amd64.zip
       - mv vault /bin/
       - mvn -B resources:testResources compiler:testCompile surefire:test
     when:

.travis.yml

@@ -7,7 +7,7 @@ addons:
       secure: "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"
 
 env:
-  - PATH=$PATH:. VAULT_VERSION=1.6.1 ANALYSIS=false
+  - PATH=$PATH:. VAULT_VERSION=1.7.0 ANALYSIS=false
 
 cache:
   directories:
@@ -18,8 +18,8 @@ jobs:
   include:
     - jdk: openjdk8
     - jdk: openjdk11
-      env: PATH=$PATH:. VAULT_VERSION=1.6.1 ANALYSIS=true
+      env: PATH=$PATH:. VAULT_VERSION=1.7.0 ANALYSIS=true
-    - jdk: openjdk15
+    - jdk: openjdk16
 
 before_script:
   - |

CHANGELOG.md

@@ -1,3 +1,21 @@
+## 0.9.3 (2021-04-02)
+
+### Improvements
+* Use pre-sized map objects for fixed-size payloads
+* Minor dependency updates
+* Unit test adjustments for JDK 16 build environments
+
+### Test
+* Tested against Vault 1.7.0
+
+## 0.9.2 (2021-01-24)
+
+### Fixes
+* Only initialize custom trust managers, if CA certificate is actually provided (#43)
+
+### Improvements
+* Minor dependency updates
+
 ## 0.9.1 (2021-01-03)
 
 ### Improvements

README.md

@@ -32,7 +32,7 @@ Java Vault Connector is a connector library for [Vault](https://www.vaultproject
     * SQL secret handling
     * KV v1 and v2 support
 * Connector Factory with builder pattern
-* Tested against Vault 1.6.1
+* Tested against Vault 1.7.0
 
 
 ## Maven Artifact
@@ -40,7 +40,7 @@ Java Vault Connector is a connector library for [Vault](https://www.vaultproject
 <dependency>
     <groupId>de.stklcode.jvault</groupId>
     <artifactId>jvault-connector</artifactId>
-    <version>0.9.1</version>
+    <version>0.9.3</version>
 </dependency>
 ```
 
@@ -86,20 +86,20 @@ vault.authAppRole("01234567-89ab-cdef-0123-456789abcdef", "fedcba98-7654-3210-fe
 
 ```java
 // Retrieve secret (prefix "secret/" assumed, use read() to read arbitrary paths)
-String secret = vault.readSecret("some/secret/key").get("value", String.class);
+String secret = vault.read("secret/some/key").get("value", String.class);
 
 // Complex secret.
-Map<String, Object> secretData = vault.readSecret("another/secret/key").getData();
+Map<String, Object> secretData = vault.read("secret/another/key").getData();
 
 // Write simple secret.
-vault.writeSecret("new/secret/key", "secret value");
+vault.write("secret/new/key", "secret value");
 
-// Write complex data to arbitraty path.
+// Write complex data.
 Map<String, Object> map = ...;
-vault.write("any/path/to/write", map);
+vault.write("path/to/write", map);
 
 // Delete secret.
-vault.delete("any/path/to/write");
+vault.delete("path/to/delete");
 ```
 
 ### Token and role creation

pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>de.stklcode.jvault</groupId>
     <artifactId>jvault-connector</artifactId>
-    <version>0.9.1</version>
+    <version>0.9.3</version>
 
     <packaging>jar</packaging>
 
@@ -23,6 +23,7 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <argLine></argLine>
     </properties>
 
     <developers>
@@ -96,6 +97,7 @@
                     <version>2.22.2</version>
                     <configuration>
                         <reuseForks>false</reuseForks>
+                        <argLine>@{argLine} --illegal-access=permit</argLine>
                     </configuration>
                 </plugin>
             </plugins>
@@ -111,13 +113,13 @@
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>2.12.0</version>
+            <version>2.12.2</version>
         </dependency>
 
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
-            <version>5.7.0</version>
+            <version>5.7.1</version>
             <scope>test</scope>
         </dependency>
         <dependency>
@@ -129,13 +131,19 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>3.6.28</version>
+            <version>3.8.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-inline</artifactId>
-            <version>3.6.28</version>
+            <version>3.8.0</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.github.stefanbirkner</groupId>
+            <artifactId>system-lambda</artifactId>
+            <version>1.2.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
@@ -151,7 +159,7 @@
             <dependency>
                 <groupId>org.sonarsource.scanner.maven</groupId>
                 <artifactId>sonar-maven-plugin</artifactId>
-                <version>3.7.0.1746</version>
+                <version>3.8.0.2131</version>
             </dependency>
         </dependencies>
     </dependencyManagement>
@@ -286,7 +294,7 @@
                     <plugin>
                         <groupId>org.owasp</groupId>
                         <artifactId>dependency-check-maven</artifactId>
-                        <version>6.0.4</version>
+                        <version>6.1.5</version>
                         <executions>
                             <execution>
                                 <goals>
@@ -299,6 +307,26 @@
             </build>
         </profile>
 
+        <profile>
+            <id>jdk1.8</id>
+            <activation>
+                <jdk>1.8</jdk>
+            </activation>
+            <build>
+                <pluginManagement>
+                    <plugins>
+                        <plugin>
+                            <groupId>org.apache.maven.plugins</groupId>
+                            <artifactId>maven-surefire-plugin</artifactId>
+                            <configuration>
+                                <argLine>@{argLine}</argLine>
+                            </configuration>
+                        </plugin>
+                    </plugins>
+                </pluginManagement>
+            </build>
+        </profile>
+
         <profile>
             <id>sonatype</id>
             <distributionManagement>
@@ -317,11 +345,11 @@
             <id>local</id>
             <distributionManagement>
                 <repository>
-                    <id>local</id>
+                    <id>stklcode</id>
                     <url>${dist.repo.local}</url>
                 </repository>
                 <snapshotRepository>
-                    <id>local</id>
+                    <id>stklcode</id>
                     <url>${dist.repo.local.snapshot}</url>
                 </snapshotRepository>
             </distributionManagement>

src/main/java/de/stklcode/jvault/connector/HTTPVaultConnector.java

@@ -30,6 +30,9 @@ import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
 
+import static java.util.Collections.emptyMap;
+import static java.util.Collections.singletonMap;
+
 /**
  * Vault Connector implementation using Vault's HTTP API.
  *
@@ -222,17 +225,17 @@ public class HTTPVaultConnector implements VaultConnector {
 
     @Override
     public final SealResponse sealStatus() throws VaultConnectorException {
-        return request.get(PATH_SEAL_STATUS, new HashMap<>(), token, SealResponse.class);
+        return request.get(PATH_SEAL_STATUS, emptyMap(), token, SealResponse.class);
     }
 
     @Override
     public final void seal() throws VaultConnectorException {
-        request.put(PATH_SEAL, new HashMap<>(), token);
+        request.put(PATH_SEAL, emptyMap(), token);
     }
 
     @Override
     public final SealResponse unseal(final String key, final Boolean reset) throws VaultConnectorException {
-        Map<String, String> param = new HashMap<>();
+        Map<String, String> param = new HashMap<>(2, 1);
         param.put("key", key);
         if (reset != null) {
             param.put("reset", reset.toString());
@@ -244,7 +247,7 @@ public class HTTPVaultConnector implements VaultConnector {
     @Override
     public HealthResponse getHealth() throws VaultConnectorException {
         /* Force status code to be 200, so we don't need to modify the request sequence. */
-        Map<String, String> param = new HashMap<>();
+        Map<String, String> param = new HashMap<>(3, 1);
         param.put("standbycode", "200");    // Default: 429.
         param.put("sealedcode", "200");     // Default: 503.
         param.put("uninitcode", "200");     // Default: 501.
@@ -260,7 +263,7 @@ public class HTTPVaultConnector implements VaultConnector {
     @Override
     public final List<AuthBackend> getAuthBackends() throws VaultConnectorException {
         /* Issue request and parse response */
-        AuthMethodsResponse amr = request.get(PATH_AUTH, new HashMap<>(), token, AuthMethodsResponse.class);
+        AuthMethodsResponse amr = request.get(PATH_AUTH, emptyMap(), token, AuthMethodsResponse.class);
 
         return amr.getSupportedMethods().values().stream().map(AuthMethod::getType).collect(Collectors.toList());
     }
@@ -270,7 +273,7 @@ public class HTTPVaultConnector implements VaultConnector {
         /* set token */
         this.token = token;
         this.tokenTTL = 0;
-        TokenResponse res = request.post(PATH_TOKEN + PATH_LOOKUP, new HashMap<>(), token, TokenResponse.class);
+        TokenResponse res = request.post(PATH_TOKEN + PATH_LOOKUP, emptyMap(), token, TokenResponse.class);
         authorized = true;
 
         return res;
@@ -279,15 +282,14 @@ public class HTTPVaultConnector implements VaultConnector {
     @Override
     public final AuthResponse authUserPass(final String username, final String password)
             throws VaultConnectorException {
-        final Map<String, String> payload = new HashMap<>();
+        final Map<String, String> payload = singletonMap("password", password);
-        payload.put("password", password);
         return queryAuth(PATH_AUTH_USERPASS + username, payload);
     }
 
     @Override
     @Deprecated
     public final AuthResponse authAppId(final String appID, final String userID) throws VaultConnectorException {
-        final Map<String, String> payload = new HashMap<>();
+        final Map<String, String> payload = new HashMap<>(2, 1);
         payload.put("app_id", appID);
         payload.put("user_id", userID);
         return queryAuth(PATH_AUTH_APPID + "login", payload);
@@ -295,7 +297,7 @@ public class HTTPVaultConnector implements VaultConnector {
 
     @Override
     public final AuthResponse authAppRole(final String roleID, final String secretID) throws VaultConnectorException {
-        final Map<String, String> payload = new HashMap<>();
+        final Map<String, String> payload = new HashMap<>(2, 1);
         payload.put("role_id", roleID);
         if (secretID != null) {
             payload.put("secret_id", secretID);
@@ -328,7 +330,7 @@ public class HTTPVaultConnector implements VaultConnector {
     public final boolean registerAppId(final String appID, final String policy, final String displayName)
             throws VaultConnectorException {
         requireAuth();
-        Map<String, String> payload = new HashMap<>();
+        Map<String, String> payload = new HashMap<>(2, 1);
         payload.put("value", policy);
         payload.put("display_name", displayName);
 
@@ -342,11 +344,13 @@ public class HTTPVaultConnector implements VaultConnector {
     @Deprecated
     public final boolean registerUserId(final String appID, final String userID) throws VaultConnectorException {
         requireAuth();
-        Map<String, String> payload = new HashMap<>();
-        payload.put("value", appID);
 
         /* Issue request and expect code 204 with empty response */
-        request.postWithoutResponse(PATH_AUTH_APPID + "map/user-id/" + userID, payload, token);
+        request.postWithoutResponse(
+                PATH_AUTH_APPID + "map/user-id/" + userID,
+                singletonMap("value", appID),
+                token
+        );
 
         return true;
     }
@@ -366,7 +370,12 @@ public class HTTPVaultConnector implements VaultConnector {
     public final AppRoleResponse lookupAppRole(final String roleName) throws VaultConnectorException {
         requireAuth();
         /* Request HTTP response and parse Secret */
-        return request.get(String.format(PATH_AUTH_APPROLE_ROLE, roleName, ""), new HashMap<>(), token, AppRoleResponse.class);
+        return request.get(
+                String.format(PATH_AUTH_APPROLE_ROLE, roleName, ""),
+                emptyMap(),
+                token,
+                AppRoleResponse.class
+        );
     }
 
     @Override
@@ -385,7 +394,7 @@ public class HTTPVaultConnector implements VaultConnector {
         /* Issue request, parse response and extract Role ID */
         return request.get(
                 String.format(PATH_AUTH_APPROLE_ROLE, roleName, "/role-id"),
-                new HashMap<>(),
+                emptyMap(),
                 token,
                 RawDataResponse.class
         ).getData().get("role_id").toString();
@@ -394,12 +403,13 @@ public class HTTPVaultConnector implements VaultConnector {
     @Override
     public final boolean setAppRoleID(final String roleName, final String roleID) throws VaultConnectorException {
         requireAuth();
-        /* Request HTTP response and parse Secret */
-        Map<String, String> payload = new HashMap<>();
-        payload.put("role_id", roleID);
 
         /* Issue request and expect code 204 with empty response */
-        request.postWithoutResponse(String.format(PATH_AUTH_APPROLE_ROLE, roleName, "/role-id"), payload, token);
+        request.postWithoutResponse(
+                String.format(PATH_AUTH_APPROLE_ROLE, roleName, "/role-id"),
+                singletonMap("role_id", roleID),
+                token
+        );
 
         return true;
     }
@@ -457,7 +467,13 @@ public class HTTPVaultConnector implements VaultConnector {
     public final List<String> listAppRoles() throws VaultConnectorException {
         requireAuth();
 
-        SecretListResponse secrets = request.get(PATH_AUTH_APPROLE + "role?list=true", new HashMap<>(), token, SecretListResponse.class);
+        SecretListResponse secrets = request.get(
+                PATH_AUTH_APPROLE + "role?list=true",
+                emptyMap(),
+                token,
+                SecretListResponse.class
+        );
+
         return secrets.getKeys();
     }
 
@@ -467,7 +483,7 @@ public class HTTPVaultConnector implements VaultConnector {
 
         SecretListResponse secrets = request.get(
                 String.format(PATH_AUTH_APPROLE_ROLE, roleName, "/secret-id?list=true"),
-                new HashMap<>(),
+                emptyMap(),
                 token,
                 SecretListResponse.class
         );
@@ -479,14 +495,14 @@ public class HTTPVaultConnector implements VaultConnector {
     public final SecretResponse read(final String key) throws VaultConnectorException {
         requireAuth();
         /* Issue request and parse secret response */
-        return request.get(key, new HashMap<>(), token, SecretResponse.class);
+        return request.get(key, emptyMap(), token, SecretResponse.class);
     }
 
     @Override
     public final SecretResponse readSecretVersion(final String mount, final String key, final Integer version) throws VaultConnectorException {
         requireAuth();
         /* Request HTTP response and parse secret metadata */
-        Map<String, String> args = new HashMap<>();
+        Map<String, String> args = new HashMap<>(1, 1);
         if (version != null) {
             args.put("version", version.toString());
         }
@@ -499,14 +515,14 @@ public class HTTPVaultConnector implements VaultConnector {
         requireAuth();
 
         /* Request HTTP response and parse secret metadata */
-        return request.get(mount + PATH_METADATA + key, new HashMap<>(), token, MetadataResponse.class);
+        return request.get(mount + PATH_METADATA + key, emptyMap(), token, MetadataResponse.class);
     }
 
     @Override
     public void updateSecretMetadata(final String mount, final String key, final Integer maxVersions, final boolean casRequired) throws VaultConnectorException {
         requireAuth();
 
-        Map<String, Object> payload = new HashMap<>();
+        Map<String, Object> payload = new HashMap<>(2, 1);
         if (maxVersions != null) {
             payload.put("max_versions", maxVersions);
         }
@@ -524,12 +540,12 @@ public class HTTPVaultConnector implements VaultConnector {
         }
 
         // Add CAS value to options map if present.
-        Map<String, Object> options = new HashMap<>();
+        Map<String, Object> options = new HashMap<>(1, 1);
         if (cas != null) {
             options.put("cas", cas);
         }
 
-        Map<String, Object> payload = new HashMap<>();
+        Map<String, Object> payload = new HashMap<>(2, 1);
         payload.put("data", data);
         payload.put("options", options);
 
@@ -541,7 +557,7 @@ public class HTTPVaultConnector implements VaultConnector {
     public final List<String> list(final String path) throws VaultConnectorException {
         requireAuth();
 
-        SecretListResponse secrets = request.get(path + "/?list=true", new HashMap<>(), token, SecretListResponse.class);
+        SecretListResponse secrets = request.get(path + "/?list=true", emptyMap(), token, SecretListResponse.class);
 
         return secrets.getKeys();
     }
@@ -559,7 +575,7 @@ public class HTTPVaultConnector implements VaultConnector {
 
         // If options are given, split payload in two parts.
         if (options != null) {
-            Map<String, Object> payloadMap = new HashMap<>();
+            Map<String, Object> payloadMap = new HashMap<>(2, 1);
             payloadMap.put("data", data);
             payloadMap.put("options", options);
             payload = payloadMap;
@@ -616,8 +632,7 @@ public class HTTPVaultConnector implements VaultConnector {
         requireAuth();
 
         /* Request HTTP response and expect empty result */
-        Map<String, Object> payload = new HashMap<>();
+        Map<String, Object> payload = singletonMap("versions", versions);
-        payload.put("versions", versions);
 
         /* Issue request and expect code 204 with empty response */
         request.postWithoutResponse(mount + pathPart + key, payload, token);
@@ -628,14 +643,14 @@ public class HTTPVaultConnector implements VaultConnector {
         requireAuth();
 
         /* Issue request and expect code 204 with empty response */
-        request.putWithoutResponse(PATH_REVOKE + leaseID, new HashMap<>(), token);
+        request.putWithoutResponse(PATH_REVOKE + leaseID, emptyMap(), token);
     }
 
     @Override
     public final SecretResponse renew(final String leaseID, final Integer increment) throws VaultConnectorException {
         requireAuth();
 
-        Map<String, String> payload = new HashMap<>();
+        Map<String, String> payload = new HashMap<>(2, 1);
         payload.put("lease_id", leaseID);
         if (increment != null) {
             payload.put("increment", increment.toString());
@@ -694,9 +709,12 @@ public class HTTPVaultConnector implements VaultConnector {
         requireAuth();
 
         /* Request HTTP response and parse Secret */
-        Map<String, String> param = new HashMap<>();
+        return request.get(
-        param.put("token", token);
+                PATH_TOKEN + PATH_LOOKUP,
-        return request.get(PATH_TOKEN + PATH_LOOKUP, param, token, TokenResponse.class);
+                singletonMap("token", token),
+                token,
+                TokenResponse.class
+        );
     }
 
     @Override
@@ -720,7 +738,7 @@ public class HTTPVaultConnector implements VaultConnector {
         requireAuth();
 
         // Request HTTP response and parse response.
-        return request.get(PATH_TOKEN + PATH_ROLES + "/" + name, new HashMap<>(), token, TokenRoleResponse.class);
+        return request.get(PATH_TOKEN + PATH_ROLES + "/" + name, emptyMap(), token, TokenRoleResponse.class);
     }
 
     @Override

src/main/java/de/stklcode/jvault/connector/VaultConnector.java

@@ -22,10 +22,7 @@ import de.stklcode.jvault.connector.model.*;
 import de.stklcode.jvault.connector.model.response.*;
 
 import java.io.Serializable;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 
 /**
  * Vault Connector interface.
@@ -611,9 +608,7 @@ public interface VaultConnector extends AutoCloseable, Serializable {
      * @since 0.5.0
      */
     default void write(final String key, final String value) throws VaultConnectorException {
-        Map<String, Object> param = new HashMap<>();
+        write(key, Collections.singletonMap("value", value));
-        param.put("value", value);
-        write(key, param);
     }
 
     /**
@@ -649,9 +644,7 @@ public interface VaultConnector extends AutoCloseable, Serializable {
      * @throws VaultConnectorException on error
      */
     default void writeSecret(final String key, final String value) throws VaultConnectorException {
-        Map<String, Object> param = new HashMap<>();
+        writeSecret(key, Collections.singletonMap("value", value));
-        param.put("value", value);
-        writeSecret(key, param);
     }
 
     /**

src/main/java/de/stklcode/jvault/connector/exception/VaultConnectorException.java

@@ -26,7 +26,7 @@ public abstract class VaultConnectorException extends Exception {
     /**
      * Constructs a new empty exception.
      */
-    public VaultConnectorException() {
+    protected VaultConnectorException() {
     }
 
     /**
@@ -34,7 +34,7 @@ public abstract class VaultConnectorException extends Exception {
      *
      * @param message the detail message
      */
-    public VaultConnectorException(final String message) {
+    protected VaultConnectorException(final String message) {
         super(message);
     }
 
@@ -43,7 +43,7 @@ public abstract class VaultConnectorException extends Exception {
      *
      * @param cause the cause
      */
-    public VaultConnectorException(final Throwable cause) {
+    protected VaultConnectorException(final Throwable cause) {
         super(cause);
     }
 
@@ -53,7 +53,7 @@ public abstract class VaultConnectorException extends Exception {
      * @param message the detail message
      * @param cause   the cause
      */
-    public VaultConnectorException(final String message, final Throwable cause) {
+    protected VaultConnectorException(final String message, final Throwable cause) {
         super(message, cause);
     }
 }

src/main/java/de/stklcode/jvault/connector/internal/RequestHelper.java

@@ -367,18 +367,22 @@ public final class RequestHelper implements Serializable {
      */
     private SSLConnectionSocketFactory createSSLSocketFactory() throws TlsException {
         try {
-            // Create Keystore with trusted certificate.
+            // Create context..
-            KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
-            keyStore.load(null, null);
-            keyStore.setCertificateEntry("trustedCert", trustedCaCert);
-
-            // Initialize TrustManager.
-            TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
-            tmf.init(keyStore);
-
-            // Create context using this TrustManager.
             SSLContext context = SSLContext.getInstance(tlsVersion);
-            context.init(null, tmf.getTrustManagers(), new SecureRandom());
+
+            if (trustedCaCert != null) {
+                // Create Keystore with trusted certificate.
+                KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
+                keyStore.load(null, null);
+                keyStore.setCertificateEntry("trustedCert", trustedCaCert);
+
+                // Initialize TrustManager.
+                TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
+                tmf.init(keyStore);
+                context.init(null, tmf.getTrustManagers(), null);
+            } else {
+                context.init(null, null, null);
+            }
 
             return new SSLConnectionSocketFactory(
                     context,

src/main/java/de/stklcode/jvault/connector/model/response/AppRoleResponse.java

@@ -40,7 +40,7 @@ public final class AppRoleResponse extends VaultDataResponse {
         ObjectMapper mapper = new ObjectMapper();
         try {
             /* null empty strings on list objects */
-            Map<String, Object> filteredData = new HashMap<>();
+            Map<String, Object> filteredData = new HashMap<>(data.size(), 1);
             data.forEach((k, v) -> {
                 if (!(v instanceof String && ((String) v).isEmpty())) {
                     filteredData.put(k, v);

src/main/java/de/stklcode/jvault/connector/model/response/AppRoleSecretResponse.java

@@ -40,7 +40,7 @@ public final class AppRoleSecretResponse extends VaultDataResponse {
         ObjectMapper mapper = new ObjectMapper();
         try {
             /* null empty strings on list objects */
-            Map<String, Object> filteredData = new HashMap<>();
+            Map<String, Object> filteredData = new HashMap<>(data.size(), 1);
             data.forEach((k, v) -> {
                 if (!(v instanceof String && ((String) v).isEmpty())) {
                     filteredData.put(k, v);

src/main/java/de/stklcode/jvault/connector/model/response/SecretResponse.java

@@ -22,7 +22,7 @@ import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import de.stklcode.jvault.connector.model.response.embedded.VersionMetadata;
 
 import java.io.IOException;
-import java.util.HashMap;
+import java.util.Collections;
 import java.util.Map;
 
 /**
@@ -66,7 +66,7 @@ public class SecretResponse extends VaultDataResponse {
      */
     public final Map<String, Object> getData() {
         if (data == null) {
-            return new HashMap<>();
+            return Collections.emptyMap();
         }
         return data;
     }

src/test/java/de/stklcode/jvault/connector/HTTPVaultConnectorOfflineTest.java

@@ -20,9 +20,6 @@ import de.stklcode.jvault.connector.exception.InvalidRequestException;
 import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import de.stklcode.jvault.connector.exception.PermissionDeniedException;
 import de.stklcode.jvault.connector.exception.VaultConnectorException;
-import net.bytebuddy.ByteBuddy;
-import net.bytebuddy.agent.ByteBuddyAgent;
-import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
 import org.apache.http.ProtocolVersion;
 import org.apache.http.client.methods.CloseableHttpResponse;
 import org.apache.http.entity.ContentType;
@@ -30,9 +27,9 @@ import org.apache.http.entity.StringEntity;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.message.BasicStatusLine;
-import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.*;
-import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.function.Executable;
-import org.junit.jupiter.api.Test;
+import org.mockito.MockedStatic;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -42,13 +39,12 @@ import java.security.cert.CertificateFactory;
 import java.security.cert.X509Certificate;
 import java.util.Collections;
 
-import static net.bytebuddy.implementation.MethodDelegation.to;
-import static net.bytebuddy.matcher.ElementMatchers.named;
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.CoreMatchers.nullValue;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.core.Is.is;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.*;
 
@@ -59,79 +55,68 @@ import static org.mockito.Mockito.*;
  * @author Stefan Kalscheuer
  * @since 0.7.0
  */
-public class HTTPVaultConnectorOfflineTest {
+class HTTPVaultConnectorOfflineTest {
     private static final String INVALID_URL = "foo:/\\1nv4l1d_UrL";
 
-    private static CloseableHttpClient httpMock = mock(CloseableHttpClient.class);
+    private static MockedStatic<HttpClientBuilder> hcbMock;
-    private CloseableHttpResponse responseMock = mock(CloseableHttpResponse.class);
+    private static CloseableHttpClient httpMock;
+    private final CloseableHttpResponse responseMock = mock(CloseableHttpResponse.class);
 
     @BeforeAll
-    public static void initByteBuddy() {
+    static void prepare() {
-        // Install ByteBuddy Agent.
+        // Mock the static HTTPClient creation.
-        ByteBuddyAgent.install();
+        hcbMock = mockStatic(HttpClientBuilder.class);
+        hcbMock.when(HttpClientBuilder::create).thenReturn(new MockedHttpClientBuilder());
     }
 
-    /**
+     @AfterAll
-     * Helper method for redefinition of {@link HttpClientBuilder#create()} from {@link #initHttpMock()}.
+     static void tearDown() {
-     *
+         hcbMock.close();
-     * @return Mocked HTTP client builder.
+     }
-     */
-    public static HttpClientBuilder create() {
-        return new MockedHttpClientBuilder();
-    }
 
     @BeforeEach
-    public void initHttpMock() {
+    void init() {
-        // Redefine static method to return Mock on HttpClientBuilder creation.
-        new ByteBuddy().redefine(HttpClientBuilder.class)
-                .method(named("create"))
-                .intercept(to(HTTPVaultConnectorOfflineTest.class))
-                .make()
-                .load(HttpClientBuilder.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
-
         // Re-initialize HTTP mock to ensure fresh (empty) results.
         httpMock = mock(CloseableHttpClient.class);
     }
 
+
     /**
      * Test exceptions thrown during request.
      */
     @Test
-    public void requestExceptionTest() throws IOException {
+    void requestExceptionTest() throws IOException {
         HTTPVaultConnector connector = new HTTPVaultConnector("http://127.0.0.1", null, 0, 250);
 
         // Test invalid response code.
         final int responseCode = 400;
         mockResponse(responseCode, "", ContentType.APPLICATION_JSON);
-        try {
+        InvalidResponseException e = assertThrows(
-            connector.getHealth();
+                InvalidResponseException.class,
-            fail("Querying health status succeeded on invalid instance");
+                connector::getHealth,
-        } catch (Exception e) {
+                "Querying health status succeeded on invalid instance"
-            assertThat("Unexpected type of exception", e, instanceOf(InvalidResponseException.class));
+        );
-            assertThat("Unexpected exception message", e.getMessage(), is("Invalid response code"));
+        assertThat("Unexpected exception message", e.getMessage(), is("Invalid response code"));
-            assertThat("Unexpected status code in exception", ((InvalidResponseException) e).getStatusCode(), is(responseCode));
+        assertThat("Unexpected status code in exception", ((InvalidResponseException) e).getStatusCode(), is(responseCode));
-            assertThat("Response message where none was expected", ((InvalidResponseException) e).getResponse(), is(nullValue()));
+        assertThat("Response message where none was expected", ((InvalidResponseException) e).getResponse(), is(nullValue()));
-        }
 
         // Simulate permission denied response.
         mockResponse(responseCode, "{\"errors\":[\"permission denied\"]}", ContentType.APPLICATION_JSON);
-        try {
+        assertThrows(
-            connector.getHealth();
+                PermissionDeniedException.class,
-            fail("Querying health status succeeded on invalid instance");
+                connector::getHealth,
-        } catch (Exception e) {
+                "Querying health status succeeded on invalid instance"
-            assertThat("Unexpected type of exception", e, instanceOf(PermissionDeniedException.class));
+        );
-        }
 
         // Test exception thrown during request.
         when(httpMock.execute(any())).thenThrow(new IOException("Test Exception"));
-        try {
+        e = assertThrows(
-            connector.getHealth();
+                InvalidResponseException.class,
-            fail("Querying health status succeeded on invalid instance");
+                connector::getHealth,
-        } catch (Exception e) {
+                "Querying health status succeeded on invalid instance"
-            assertThat("Unexpected type of exception", e, instanceOf(InvalidResponseException.class));
+        );
-            assertThat("Unexpected exception message", e.getMessage(), is("Unable to read response"));
+        assertThat("Unexpected exception message", e.getMessage(), is("Unable to read response"));
-            assertThat("Unexpected cause", e.getCause(), instanceOf(IOException.class));
+        assertThat("Unexpected cause", e.getCause(), instanceOf(IOException.class));
-        }
 
         // Now simulate a failing request that succeeds on second try.
         connector = new HTTPVaultConnector("https://127.0.0.1", null, 1, 250);
@@ -143,18 +128,14 @@ public class HTTPVaultConnectorOfflineTest {
                 .when(responseMock).getStatusLine();
         when(responseMock.getEntity()).thenReturn(new StringEntity("{}", ContentType.APPLICATION_JSON));
 
-        try {
+        assertDoesNotThrow(connector::getHealth, "Request failed unexpectedly");
-            connector.getHealth();
-        } catch (Exception e) {
-            fail("Request failed unexpectedly: " + e.getMessage());
-        }
     }
 
     /**
      * Test constructors of the {@link HTTPVaultConnector} class.
      */
     @Test
-    public void constructorTest() throws IOException, CertificateException {
+    void constructorTest() throws IOException, CertificateException {
         final String url = "https://vault.example.net/test/";
         final String hostname = "vault.example.com";
         final Integer port = 1337;
@@ -206,60 +187,53 @@ public class HTTPVaultConnectorOfflineTest {
      * This test is designed to test exceptions caught and thrown by seal-methods if Vault is not reachable.
      */
     @Test
-    public void sealExceptionTest() throws IOException {
+    void sealExceptionTest() {
         HTTPVaultConnector connector = new HTTPVaultConnector(INVALID_URL);
-        try {
+        VaultConnectorException e = assertThrows(
-            connector.sealStatus();
+                InvalidRequestException.class,
-            fail("Querying seal status succeeded on invalid URL");
+                connector::sealStatus,
-        } catch (Exception e) {
+                "Querying seal status succeeded on invalid URL"
-            assertThat("Unexpected type of exception", e, instanceOf(InvalidRequestException.class));
+        );
-            assertThat("Unexpected exception message", e.getMessage(), is("Invalid URI format"));
+        assertThat("Unexpected exception message", e.getMessage(), is("Invalid URI format"));
-        }
-
-        connector = new HTTPVaultConnector("https://127.0.0.1", null, 0, 250);
 
         // Simulate NULL response (mock not supplied with data).
-
+        connector = new HTTPVaultConnector("https://127.0.0.1", null, 0, 250);
-        try {
+        e = assertThrows(
-            connector.sealStatus();
+                InvalidResponseException.class,
-            fail("Querying seal status succeeded on invalid instance");
+                connector::sealStatus,
-        } catch (Exception e) {
+                "Querying seal status succeeded on invalid instance"
-            assertThat("Unexpected type of exception", e, instanceOf(InvalidResponseException.class));
+        );
-            assertThat("Unexpected exception message", e.getMessage(), is("Response unavailable"));
+        assertThat("Unexpected exception message", e.getMessage(), is("Response unavailable"));
-        }
     }
 
     /**
      * This test is designed to test exceptions caught and thrown by seal-methods if Vault is not reachable.
      */
     @Test
-    public void healthExceptionTest() throws IOException {
+    void healthExceptionTest() {
         HTTPVaultConnector connector = new HTTPVaultConnector(INVALID_URL);
-        try {
+        VaultConnectorException e = assertThrows(
-            connector.getHealth();
+                InvalidRequestException.class,
-            fail("Querying health status succeeded on invalid URL");
+                connector::getHealth,
-        } catch (Exception e) {
+                "Querying health status succeeded on invalid URL"
-            assertThat("Unexpected type of exception", e, instanceOf(InvalidRequestException.class));
+        );
-            assertThat("Unexpected exception message", e.getMessage(), is("Invalid URI format"));
+        assertThat("Unexpected exception message", e.getMessage(), is("Invalid URI format"));
-        }
-
-        connector = new HTTPVaultConnector("https://127.0.0.1", null, 0, 250);
 
         // Simulate NULL response (mock not supplied with data).
-        try {
+        connector = new HTTPVaultConnector("https://127.0.0.1", null, 0, 250);
-            connector.getHealth();
+        e = assertThrows(
-            fail("Querying health status succeeded on invalid instance");
+                InvalidResponseException.class,
-        } catch (Exception e) {
+                connector::getHealth,
-            assertThat("Unexpected type of exception", e, instanceOf(InvalidResponseException.class));
+                "Querying health status succeeded on invalid instance"
-            assertThat("Unexpected exception message", e.getMessage(), is("Response unavailable"));
+        );
-        }
+        assertThat("Unexpected exception message", e.getMessage(), is("Response unavailable"));
     }
 
     /**
      * Test behavior on unparsable responses.
      */
     @Test
-    public void parseExceptionTest() throws IOException {
+    void parseExceptionTest() throws IOException {
         HTTPVaultConnector connector = new HTTPVaultConnector("https://127.0.0.1", null, 0, 250);
         // Mock authorization.
         setPrivate(connector, "authorized", true);
@@ -267,114 +241,25 @@ public class HTTPVaultConnectorOfflineTest {
         mockResponse(200, "invalid", ContentType.APPLICATION_JSON);
 
         // Now test the methods.
-        try {
+        assertParseError(connector::sealStatus, "sealStatus() succeeded on invalid instance");
-            connector.sealStatus();
+        assertParseError(() -> connector.unseal("key"), "unseal() succeeded on invalid instance");
-            fail("sealStatus() succeeded on invalid instance");
+        assertParseError(connector::getHealth, "getHealth() succeeded on invalid instance");
-        } catch (Exception e) {
+        assertParseError(connector::getAuthBackends, "getAuthBackends() succeeded on invalid instance");
-            assertParseError(e);
+        assertParseError(() -> connector.authToken("token"), "authToken() succeeded on invalid instance");
-        }
+        assertParseError(() -> connector.lookupAppRole("roleName"), "lookupAppRole() succeeded on invalid instance");
-
+        assertParseError(() -> connector.getAppRoleID("roleName"), "getAppRoleID() succeeded on invalid instance");
-        try {
+        assertParseError(() -> connector.createAppRoleSecret("roleName"), "createAppRoleSecret() succeeded on invalid instance");
-            connector.unseal("key");
+        assertParseError(() -> connector.lookupAppRoleSecret("roleName", "secretID"), "lookupAppRoleSecret() succeeded on invalid instance");
-            fail("unseal() succeeded on invalid instance");
+        assertParseError(connector::listAppRoles, "listAppRoles() succeeded on invalid instance");
-        } catch (Exception e) {
+        assertParseError(() -> connector.listAppRoleSecrets("roleName"), "listAppRoleSecrets() succeeded on invalid instance");
-            assertParseError(e);
+        assertParseError(() -> connector.read("key"), "read() succeeded on invalid instance");
-        }
+        assertParseError(() -> connector.list("path"), "list() succeeded on invalid instance");
-
+        assertParseError(() -> connector.renew("leaseID"), "renew() succeeded on invalid instance");
-        try {
+        assertParseError(() -> connector.lookupToken("token"), "lookupToken() succeeded on invalid instance");
-            connector.getHealth();
-            fail("getHealth() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.getAuthBackends();
-            fail("getAuthBackends() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.authToken("token");
-            fail("authToken() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.lookupAppRole("roleName");
-            fail("lookupAppRole() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.getAppRoleID("roleName");
-            fail("getAppRoleID() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.createAppRoleSecret("roleName");
-            fail("createAppRoleSecret() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.lookupAppRoleSecret("roleName", "secretID");
-            fail("lookupAppRoleSecret() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.listAppRoles();
-            fail("listAppRoles() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.listAppRoleSecrets("roleName");
-            fail("listAppRoleSecrets() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.read("key");
-            fail("read() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.list("path");
-            fail("list() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.renew("leaseID");
-            fail("renew() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
-
-        try {
-            connector.lookupToken("token");
-            fail("lookupToken() succeeded on invalid instance");
-        } catch (Exception e) {
-            assertParseError(e);
-        }
     }
 
-    private void assertParseError(Exception e) {
+    private void assertParseError(Executable executable, String message) {
-        assertThat("Unexpected type of exception", e, instanceOf(InvalidResponseException.class));
+        InvalidResponseException e = assertThrows(InvalidResponseException.class, executable, message);
         assertThat("Unexpected exception message", e.getMessage(), is("Unable to parse response"));
     }
 
@@ -382,7 +267,7 @@ public class HTTPVaultConnectorOfflineTest {
      * Test requests that expect an empty response with code 204, but receive a 200 body.
      */
     @Test
-    public void nonEmpty204ResponseTest() throws IOException {
+    void nonEmpty204ResponseTest() throws IOException {
         HTTPVaultConnector connector = new HTTPVaultConnector("https://127.0.0.1", null, 0, 250);
         // Mock authorization.
         setPrivate(connector, "authorized", true);
@@ -390,71 +275,62 @@ public class HTTPVaultConnectorOfflineTest {
         mockResponse(200, "{}", ContentType.APPLICATION_JSON);
 
         // Now test the methods expecting a 204.
-        try {
+        assertThrows(
-            connector.registerAppId("appID", "policy", "displayName");
+                InvalidResponseException.class,
-            fail("registerAppId() with 200 response succeeded");
+                () -> connector.registerAppId("appID", "policy", "displayName"),
-        } catch (VaultConnectorException e) {
+                "registerAppId() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.registerUserId("appID", "userID");
+                InvalidResponseException.class,
-            fail("registerUserId() with 200 response succeeded");
+                () -> connector.registerUserId("appID", "userID"),
-        } catch (VaultConnectorException e) {
+                "registerUserId() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.createAppRole("appID", Collections.singletonList("policy"));
+                InvalidResponseException.class,
-            fail("createAppRole() with 200 response succeeded");
+                () -> connector.createAppRole("appID", Collections.singletonList("policy")),
-        } catch (VaultConnectorException e) {
+                "createAppRole() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.deleteAppRole("roleName");
+                InvalidResponseException.class,
-            fail("deleteAppRole() with 200 response succeeded");
+                () -> connector.deleteAppRole("roleName"),
-        } catch (VaultConnectorException e) {
+                "deleteAppRole() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.setAppRoleID("roleName", "roleID");
+                InvalidResponseException.class,
-            fail("setAppRoleID() with 200 response succeeded");
+                () -> connector.setAppRoleID("roleName", "roleID"),
-        } catch (VaultConnectorException e) {
+                "setAppRoleID() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.destroyAppRoleSecret("roleName", "secretID");
+                InvalidResponseException.class,
-            fail("destroyAppRoleSecret() with 200 response succeeded");
+                () -> connector.destroyAppRoleSecret("roleName", "secretID"),
-        } catch (VaultConnectorException e) {
+                "destroyAppRoleSecret() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.destroyAppRoleSecret("roleName", "secretUD");
+                InvalidResponseException.class,
-            fail("destroyAppRoleSecret() with 200 response succeeded");
+                () -> connector.destroyAppRoleSecret("roleName", "secretUD"),
-        } catch (VaultConnectorException e) {
+                "destroyAppRoleSecret() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.delete("key");
+                InvalidResponseException.class,
-            fail("delete() with 200 response succeeded");
+                () -> connector.delete("key"),
-        } catch (VaultConnectorException e) {
+                "delete() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
-        try {
+        assertThrows(
-            connector.revoke("leaseID");
+                InvalidResponseException.class,
-            fail("destroyAppRoleSecret() with 200 response succeeded");
+                () -> connector.revoke("leaseID"),
-        } catch (VaultConnectorException e) {
+                "destroyAppRoleSecret() with 200 response succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
     }
 
-    private Object getRequestHelperPrivate(HTTPVaultConnector connector, String fieldName)  {
+    private Object getRequestHelperPrivate(HTTPVaultConnector connector, String fieldName) {
         try {
             return getPrivate(getPrivate(connector, "request"), fieldName);
         } catch (NoSuchFieldException | IllegalAccessException e) {

src/test/java/de/stklcode/jvault/connector/builder/HTTPVaultConnectorBuilderTest.java

@@ -16,21 +16,22 @@
 
 package de.stklcode.jvault.connector.builder;
 
+import com.github.stefanbirkner.systemlambda.SystemLambda;
 import de.stklcode.jvault.connector.HTTPVaultConnector;
 import de.stklcode.jvault.connector.exception.TlsException;
-import de.stklcode.jvault.connector.exception.VaultConnectorException;
-import de.stklcode.jvault.connector.test.EnvironmentMock;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
 
 import java.io.File;
-import java.io.IOException;
 import java.lang.reflect.Field;
 import java.nio.file.NoSuchFileException;
+import java.util.concurrent.Callable;
 
+import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
 import static org.hamcrest.CoreMatchers.*;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit test for HTTP Vault connector factory
@@ -38,7 +39,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.8.0
  */
-public class HTTPVaultConnectorBuilderTest {
+class HTTPVaultConnectorBuilderTest {
     private static final String VAULT_ADDR = "https://localhost:8201";
     private static final Integer VAULT_MAX_RETRIES = 13;
     private static final String VAULT_TOKEN = "00001111-2222-3333-4444-555566667777";
@@ -50,66 +51,68 @@ public class HTTPVaultConnectorBuilderTest {
      * Test building from environment variables
      */
     @Test
-    void testFromEnv() throws NoSuchFieldException, IllegalAccessException, IOException {
+    void testFromEnv() throws Exception {
         /* Provide address only should be enough */
-        setenv(VAULT_ADDR, null, null, null);
+        withVaultEnv(VAULT_ADDR, null, null, null).execute(() -> {
+            HTTPVaultConnectorBuilder builder = assertDoesNotThrow(
+                    () -> VaultConnectorBuilder.http().fromEnv(),
+                    "Factory creation from minimal environment failed"
+            );
+            HTTPVaultConnector connector = builder.build();
 
-        HTTPVaultConnectorBuilder factory = null;
+            assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
-        HTTPVaultConnector connector;
+            assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
-        try {
+            assertThat("Non-default number of retries, when none set", getRequestHelperPrivate(connector, "retries"), is(0));
-            factory = VaultConnectorBuilder.http().fromEnv();
-        } catch (VaultConnectorException e) {
-            fail("Factory creation from minimal environment failed");
-        }
-        connector = factory.build();
 
-        assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
+            return null;
-        assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
+        });
-        assertThat("Non-default number of retries, when none set", getRequestHelperPrivate(connector, "retries"), is(0));
 
         /* Provide address and number of retries */
-        setenv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), null);
+        withVaultEnv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), null).execute(() -> {
+            HTTPVaultConnectorBuilder builder = assertDoesNotThrow(
+                    () -> VaultConnectorBuilder.http().fromEnv(),
+                    "Factory creation from environment failed"
+            );
+            HTTPVaultConnector connector = builder.build();
 
-        try {
+            assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
-            factory = VaultConnectorBuilder.http().fromEnv();
+            assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
-        } catch (VaultConnectorException e) {
+            assertThat("Number of retries not set correctly", getRequestHelperPrivate(connector, "retries"), is(VAULT_MAX_RETRIES));
-            fail("Factory creation from environment failed");
-        }
-        connector = factory.build();
 
-        assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
+            return null;
-        assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
+        });
-        assertThat("Number of retries not set correctly", getRequestHelperPrivate(connector, "retries"), is(VAULT_MAX_RETRIES));
 
         /* Provide CA certificate */
         String VAULT_CACERT = tempDir.toString() + "/doesnotexist";
-        setenv(VAULT_ADDR, VAULT_CACERT, VAULT_MAX_RETRIES.toString(), null);
+        withVaultEnv(VAULT_ADDR, VAULT_CACERT, VAULT_MAX_RETRIES.toString(), null).execute(() -> {
-
+            TlsException e = assertThrows(
-        try {
+                    TlsException.class,
-            VaultConnectorBuilder.http().fromEnv();
+                    () -> VaultConnectorBuilder.http().fromEnv(),
-            fail("Creation with unknown cert path failed.");
+                    "Creation with unknown cert path failed."
-        } catch (VaultConnectorException e) {
+            );
-            assertThat(e, is(instanceOf(TlsException.class)));
             assertThat(e.getCause(), is(instanceOf(NoSuchFileException.class)));
             assertThat(((NoSuchFileException) e.getCause()).getFile(), is(VAULT_CACERT));
-        }
+
+            return null;
+        });
 
         /* Automatic authentication */
-        setenv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), VAULT_TOKEN);
+        withVaultEnv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), VAULT_TOKEN).execute(() -> {
+            HTTPVaultConnectorBuilder builder = assertDoesNotThrow(
+                    () -> VaultConnectorBuilder.http().fromEnv(),
+                    "Factory creation from minimal environment failed"
+            );
+            assertThat("Token nor set correctly", getPrivate(builder, "token"), is(equalTo(VAULT_TOKEN)));
 
-        try {
+            return null;
-            factory = VaultConnectorBuilder.http().fromEnv();
+        });
-        } catch (VaultConnectorException e) {
-            fail("Factory creation from minimal environment failed");
-        }
-        assertThat("Token nor set correctly", getPrivate(factory, "token"), is(equalTo(VAULT_TOKEN)));
     }
 
-    private void setenv(String vault_addr, String vault_cacert, String vault_max_retries, String vault_token) {
+    private SystemLambda.WithEnvironmentVariables withVaultEnv(String vault_addr, String vault_cacert, String vault_max_retries, String vault_token) {
-        EnvironmentMock.setenv("VAULT_ADDR", vault_addr);
+        return withEnvironmentVariable("VAULT_ADDR", vault_addr)
-        EnvironmentMock.setenv("VAULT_CACERT", vault_cacert);
+                .and("VAULT_CACERT", vault_cacert)
-        EnvironmentMock.setenv("VAULT_MAX_RETRIES", vault_max_retries);
+                .and("VAULT_MAX_RETRIES", vault_max_retries)
-        EnvironmentMock.setenv("VAULT_TOKEN", vault_token);
+                .and("VAULT_TOKEN", vault_token);
     }
 
     private Object getRequestHelperPrivate(HTTPVaultConnector connector, String fieldName) throws NoSuchFieldException, IllegalAccessException {

src/test/java/de/stklcode/jvault/connector/exception/VaultConnectorExceptionTest.java

@@ -29,19 +29,19 @@ import static org.hamcrest.core.Is.is;
  * @author Stefan Kalscheuer
  * @since 0.6.2
  */
-public class VaultConnectorExceptionTest {
+class VaultConnectorExceptionTest {
     private static final String MSG = "This is a test exception!";
     private static final Throwable CAUSE = new Exception("Test-Cause");
     private static final Integer STATUS_CODE = 1337;
     private static final String RESPONSE = "Dummy response";
 
     @Test
-    public void authorizationRequiredExceptionTest() {
+    void authorizationRequiredExceptionTest() {
         assertEmptyConstructor(new AuthorizationRequiredException());
     }
 
     @Test
-    public void connectionExceptionTest() {
+    void connectionExceptionTest() {
         assertEmptyConstructor(new ConnectionException());
         assertMsgConstructor(new ConnectionException(MSG));
         assertCauseConstructor(new ConnectionException(CAUSE));
@@ -49,7 +49,7 @@ public class VaultConnectorExceptionTest {
     }
 
     @Test
-    public void invalidRequestExceptionTest() {
+    void invalidRequestExceptionTest() {
         assertEmptyConstructor(new InvalidRequestException());
         assertMsgConstructor(new InvalidRequestException(MSG));
         assertCauseConstructor(new InvalidRequestException(CAUSE));
@@ -57,7 +57,7 @@ public class VaultConnectorExceptionTest {
     }
 
     @Test
-    public void invalidResponseExceptionTest() {
+    void invalidResponseExceptionTest() {
         assertEmptyConstructor(new InvalidResponseException());
         assertMsgConstructor(new InvalidResponseException(MSG));
         assertCauseConstructor(new InvalidResponseException(CAUSE));
@@ -93,7 +93,7 @@ public class VaultConnectorExceptionTest {
     }
 
     @Test
-    public void permissionDeniedExceptionTest() {
+    void permissionDeniedExceptionTest() {
         // Default message overwritten.
         PermissionDeniedException e = new PermissionDeniedException();
         assertThat(e, is(instanceOf(VaultConnectorException.class)));
@@ -108,7 +108,7 @@ public class VaultConnectorExceptionTest {
     }
 
     @Test
-    public void tlsExceptionTest() {
+    void tlsExceptionTest() {
         assertEmptyConstructor(new TlsException());
         assertMsgConstructor(new TlsException(MSG));
         assertCauseConstructor(new TlsException(CAUSE));

src/test/java/de/stklcode/jvault/connector/factory/HTTPVaultConnectorFactoryTest.java

@@ -16,21 +16,21 @@
 
 package de.stklcode.jvault.connector.factory;
 
+import com.github.stefanbirkner.systemlambda.SystemLambda;
 import de.stklcode.jvault.connector.HTTPVaultConnector;
 import de.stklcode.jvault.connector.exception.TlsException;
-import de.stklcode.jvault.connector.exception.VaultConnectorException;
-import de.stklcode.jvault.connector.test.EnvironmentMock;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
 
 import java.io.File;
-import java.io.IOException;
 import java.lang.reflect.Field;
 import java.nio.file.NoSuchFileException;
 
+import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
 import static org.hamcrest.CoreMatchers.*;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit test for HTTP Vault connector factory
@@ -38,7 +38,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.6.0
  */
-public class HTTPVaultConnectorFactoryTest {
+class HTTPVaultConnectorFactoryTest {
     private static String VAULT_ADDR = "https://localhost:8201";
     private static Integer VAULT_MAX_RETRIES = 13;
     private static String VAULT_TOKEN = "00001111-2222-3333-4444-555566667777";
@@ -50,66 +50,68 @@ public class HTTPVaultConnectorFactoryTest {
      * Test building from environment variables
      */
     @Test
-    public void testFromEnv() throws NoSuchFieldException, IllegalAccessException, IOException {
+    void testFromEnv() throws Exception {
         /* Provide address only should be enough */
-        setenv(VAULT_ADDR, null, null, null);
+        withVaultEnv(VAULT_ADDR, null, null, null).execute(() -> {
+            HTTPVaultConnectorFactory factory = assertDoesNotThrow(
+                    () -> VaultConnectorFactory.httpFactory().fromEnv(),
+                    "Factory creation from minimal environment failed"
+            );
+            HTTPVaultConnector connector = factory.build();
 
-        HTTPVaultConnectorFactory factory = null;
+            assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
-        HTTPVaultConnector connector;
+            assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
-        try {
+            assertThat("Non-default number of retries, when none set", getRequestHelperPrivate(connector, "retries"), is(0));
-            factory = VaultConnectorFactory.httpFactory().fromEnv();
-        } catch (VaultConnectorException e) {
-            fail("Factory creation from minimal environment failed");
-        }
-        connector = factory.build();
 
-        assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
+            return null;
-        assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
+        });
-        assertThat("Non-default number of retries, when none set", getRequestHelperPrivate(connector, "retries"), is(0));
 
         /* Provide address and number of retries */
-        setenv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), null);
+        withVaultEnv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), null).execute(() -> {
+            HTTPVaultConnectorFactory factory = assertDoesNotThrow(
+                    () -> VaultConnectorFactory.httpFactory().fromEnv(),
+                    "Factory creation from environment failed"
+            );
+            HTTPVaultConnector connector = factory.build();
 
-        try {
+            assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
-            factory = VaultConnectorFactory.httpFactory().fromEnv();
+            assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
-        } catch (VaultConnectorException e) {
+            assertThat("Number of retries not set correctly", getRequestHelperPrivate(connector, "retries"), is(VAULT_MAX_RETRIES));
-            fail("Factory creation from environment failed");
-        }
-        connector = factory.build();
 
-        assertThat("URL nor set correctly", getRequestHelperPrivate(connector, "baseURL"), is(equalTo(VAULT_ADDR + "/v1/")));
+            return null;
-        assertThat("Trusted CA cert set when no cert provided", getRequestHelperPrivate(connector, "trustedCaCert"), is(nullValue()));
+        });
-        assertThat("Number of retries not set correctly", getRequestHelperPrivate(connector, "retries"), is(VAULT_MAX_RETRIES));
 
         /* Provide CA certificate */
         String VAULT_CACERT = tempDir.toString() + "/doesnotexist";
-        setenv(VAULT_ADDR, VAULT_CACERT, VAULT_MAX_RETRIES.toString(), null);
+        withVaultEnv(VAULT_ADDR, VAULT_CACERT, VAULT_MAX_RETRIES.toString(), null).execute(() -> {
-
+            TlsException e = assertThrows(
-        try {
+                    TlsException.class,
-            VaultConnectorFactory.httpFactory().fromEnv();
+                    () -> VaultConnectorFactory.httpFactory().fromEnv(),
-            fail("Creation with unknown cert path failed.");
+                    "Creation with unknown cert path failed."
-        } catch (VaultConnectorException e) {
+            );
-            assertThat(e, is(instanceOf(TlsException.class)));
             assertThat(e.getCause(), is(instanceOf(NoSuchFileException.class)));
             assertThat(((NoSuchFileException) e.getCause()).getFile(), is(VAULT_CACERT));
-        }
+
+            return null;
+        });
 
         /* Automatic authentication */
-        setenv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), VAULT_TOKEN);
+        withVaultEnv(VAULT_ADDR, null, VAULT_MAX_RETRIES.toString(), VAULT_TOKEN).execute(() -> {
+            HTTPVaultConnectorFactory factory = assertDoesNotThrow(
+                    () -> VaultConnectorFactory.httpFactory().fromEnv(),
+                    "Factory creation from minimal environment failed"
+            );
+            assertThat("Token nor set correctly", getPrivate(getPrivate(factory, "delegate"), "token"), is(equalTo(VAULT_TOKEN)));
 
-        try {
+            return null;
-            factory = VaultConnectorFactory.httpFactory().fromEnv();
+        });
-        } catch (VaultConnectorException e) {
-            fail("Factory creation from minimal environment failed");
-        }
-        assertThat("Token nor set correctly", getPrivate(getPrivate(factory, "delegate"), "token"), is(equalTo(VAULT_TOKEN)));
     }
 
-    private void setenv(String vault_addr, String vault_cacert, String vault_max_retries, String vault_token) {
+    private SystemLambda.WithEnvironmentVariables withVaultEnv(String vault_addr, String vault_cacert, String vault_max_retries, String vault_token) {
-        EnvironmentMock.setenv("VAULT_ADDR", vault_addr);
+        return withEnvironmentVariable("VAULT_ADDR", vault_addr)
-        EnvironmentMock.setenv("VAULT_CACERT", vault_cacert);
+                .and("VAULT_CACERT", vault_cacert)
-        EnvironmentMock.setenv("VAULT_MAX_RETRIES", vault_max_retries);
+                .and("VAULT_MAX_RETRIES", vault_max_retries)
-        EnvironmentMock.setenv("VAULT_TOKEN", vault_token);
+                .and("VAULT_TOKEN", vault_token);
     }
 
     private Object getRequestHelperPrivate(HTTPVaultConnector connector, String fieldName) throws NoSuchFieldException, IllegalAccessException {

src/test/java/de/stklcode/jvault/connector/model/AppRoleBuilderTest.java

@@ -33,7 +33,7 @@ import static org.hamcrest.Matchers.*;
  * @author Stefan Kalscheuer
  * @since 0.4.0
  */
-public class AppRoleBuilderTest {
+class AppRoleBuilderTest {
     private static final String NAME = "TestRole";
     private static final String ID = "test-id";
     private static final Boolean BIND_SECRET_ID = true;
@@ -58,7 +58,7 @@ public class AppRoleBuilderTest {
             NAME, ID, BIND_SECRET_ID, CIDR_1, SECRET_ID_NUM_USES, SECRET_ID_TTL, ENABLE_LOCAL_SECRET_IDS, TOKEN_TTL, TOKEN_MAX_TTL, POLICY, CIDR_1, TOKEN_EXPLICIT_MAX_TTL, TOKEN_NO_DEFAULT_POLICY, TOKEN_NUM_USES, TOKEN_PERIOD, TOKEN_TYPE.value());
 
     @BeforeAll
-    public static void init() {
+    static void init() {
         BOUND_CIDR_LIST.add(CIDR_1);
         POLICIES.add(POLICY);
     }
@@ -67,7 +67,7 @@ public class AppRoleBuilderTest {
      * Build role with only a name.
      */
     @Test
-    public void buildDefaultTest() throws JsonProcessingException {
+    void buildDefaultTest() throws JsonProcessingException {
         AppRole role = AppRole.builder(NAME).build();
         assertThat(role.getId(), is(nullValue()));
         assertThat(role.getBindSecretId(), is(nullValue()));
@@ -95,7 +95,7 @@ public class AppRoleBuilderTest {
      * Build role with only a name.
      */
     @Test
-    public void legacyBuildDefaultTest() throws JsonProcessingException {
+    void legacyBuildDefaultTest() throws JsonProcessingException {
         AppRole role = new AppRoleBuilder(NAME).build();
         assertThat(role.getId(), is(nullValue()));
         assertThat(role.getBindSecretId(), is(nullValue()));
@@ -123,7 +123,7 @@ public class AppRoleBuilderTest {
      * Build token without all parameters set.
      */
     @Test
-    public void buildFullTest() throws JsonProcessingException {
+    void buildFullTest() throws JsonProcessingException {
         AppRole role = AppRole.builder(NAME)
                 .withId(ID)
                 .withBindSecretID(BIND_SECRET_ID)
@@ -168,7 +168,7 @@ public class AppRoleBuilderTest {
      * Build token without all parameters set.
      */
     @Test
-    public void legacyBuildFullTest() throws JsonProcessingException {
+    void legacyBuildFullTest() throws JsonProcessingException {
         AppRole role = new AppRoleBuilder(NAME)
                 .withId(ID)
                 .withBindSecretID(BIND_SECRET_ID)
@@ -213,7 +213,7 @@ public class AppRoleBuilderTest {
      * Test convenience methods
      */
     @Test
-    public void convenienceMethodsTest() {
+    void convenienceMethodsTest() {
         /* bind_secret_id */
         AppRole role = AppRole.builder(NAME).build();
         assertThat(role.getBindSecretId(), is(nullValue()));
@@ -257,7 +257,7 @@ public class AppRoleBuilderTest {
      * Test convenience methods
      */
     @Test
-    public void legacyConvenienceMethodsTest() {
+    void legacyConvenienceMethodsTest() {
         /* bind_secret_id */
         AppRole role = new AppRoleBuilder(NAME).build();
         assertThat(role.getBindSecretId(), is(nullValue()));

src/test/java/de/stklcode/jvault/connector/model/AppRoleSecretTest.java

@@ -16,11 +16,9 @@
 
 package de.stklcode.jvault.connector.model;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.lang.reflect.Field;
 import java.util.Arrays;
 import java.util.HashMap;
@@ -29,7 +27,7 @@ import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assumptions.assumeTrue;
 
 
@@ -39,7 +37,7 @@ import static org.junit.jupiter.api.Assumptions.assumeTrue;
  * @author Stefan Kalscheuer
  * @since 0.5.0
  */
-public class AppRoleSecretTest {
+class AppRoleSecretTest {
 
     private static final String TEST_ID = "abc123";
     private static final Map<String, Object> TEST_META = new HashMap<>();
@@ -54,7 +52,7 @@ public class AppRoleSecretTest {
      * Test constructors.
      */
     @Test
-    public void constructorTest() {
+    void constructorTest() {
         /* Empty constructor */
         AppRoleSecret secret = new AppRoleSecret();
         assertThat(secret.getId(), is(nullValue()));
@@ -99,7 +97,7 @@ public class AppRoleSecretTest {
      * Test setter.
      */
     @Test
-    public void setterTest() {
+    void setterTest() {
         AppRoleSecret secret = new AppRoleSecret(TEST_ID);
         assertThat(secret.getCidrList(), is(nullValue()));
         assertThat(secret.getCidrListString(), is(emptyString()));
@@ -115,31 +113,22 @@ public class AppRoleSecretTest {
      * Test JSON (de)serialization.
      */
     @Test
-    public void jsonTest() throws NoSuchFieldException, IllegalAccessException {
+    void jsonTest() throws NoSuchFieldException, IllegalAccessException {
         ObjectMapper mapper = new ObjectMapper();
 
         /* A simple roundtrip first. All set fields should be present afterwards. */
         AppRoleSecret secret = new AppRoleSecret(TEST_ID, TEST_META, TEST_CIDR);
-        String secretJson = "";
+        String secretJson = assertDoesNotThrow(() -> mapper.writeValueAsString(secret), "Serialization failed");
-        try {
-            secretJson = mapper.writeValueAsString(secret);
-        } catch (JsonProcessingException e) {
-            e.printStackTrace();
-            fail("Serialization failed");
-        }
         /* CIDR list is comma-separated when used as input, but List otherwise, hence convert string to list */
-        secretJson = commaSeparatedToList(secretJson);
+        String secretJson2 = commaSeparatedToList(secretJson);
 
-        AppRoleSecret secret2;
+        AppRoleSecret secret2 = assertDoesNotThrow(
-        try {
+                () -> mapper.readValue(secretJson2, AppRoleSecret.class),
-            secret2 = mapper.readValue(secretJson, AppRoleSecret.class);
+                "Deserialization failed"
-            assertThat(secret.getId(), is(secret2.getId()));
+        );
-            assertThat(secret.getMetadata(), is(secret2.getMetadata()));
+        assertThat(secret.getId(), is(secret2.getId()));
-            assertThat(secret.getCidrList(), is(secret2.getCidrList()));
+        assertThat(secret.getMetadata(), is(secret2.getMetadata()));
-        } catch (IOException e) {
+        assertThat(secret.getCidrList(), is(secret2.getCidrList()));
-            e.printStackTrace();
-            fail("Deserialization failed");
-        }
 
         /* Test fields, that should not be written to JSON */
         setPrivateField(secret, "accessor", "TEST_ACCESSOR");
@@ -154,45 +143,33 @@ public class AppRoleSecretTest {
         assumeTrue(secret.getNumUses() == 678);
         setPrivateField(secret, "ttl", 12345);
         assumeTrue(secret.getTtl() == 12345);
-        try {
+        String secretJson3 = assertDoesNotThrow(() -> mapper.writeValueAsString(secret), "Serialization failed");
-            secretJson = mapper.writeValueAsString(secret);
+        secret2 = assertDoesNotThrow(
-        } catch (JsonProcessingException e) {
+                () -> mapper.readValue(commaSeparatedToList(secretJson3), AppRoleSecret.class),
-            e.printStackTrace();
+                "Deserialization failed"
-            fail("Serialization failed");
+        );
-        }
+        assertThat(secret.getId(), is(secret2.getId()));
-        try {
+        assertThat(secret.getMetadata(), is(secret2.getMetadata()));
-            secret2 = mapper.readValue(commaSeparatedToList(secretJson), AppRoleSecret.class);
+        assertThat(secret.getCidrList(), is(secret2.getCidrList()));
-            assertThat(secret.getId(), is(secret2.getId()));
+        assertThat(secret2.getAccessor(), is(nullValue()));
-            assertThat(secret.getMetadata(), is(secret2.getMetadata()));
+        assertThat(secret2.getCreationTime(), is(nullValue()));
-            assertThat(secret.getCidrList(), is(secret2.getCidrList()));
+        assertThat(secret2.getExpirationTime(), is(nullValue()));
-            assertThat(secret2.getAccessor(), is(nullValue()));
+        assertThat(secret2.getLastUpdatedTime(), is(nullValue()));
-            assertThat(secret2.getCreationTime(), is(nullValue()));
+        assertThat(secret2.getNumUses(), is(nullValue()));
-            assertThat(secret2.getExpirationTime(), is(nullValue()));
+        assertThat(secret2.getTtl(), is(nullValue()));
-            assertThat(secret2.getLastUpdatedTime(), is(nullValue()));
-            assertThat(secret2.getNumUses(), is(nullValue()));
-            assertThat(secret2.getTtl(), is(nullValue()));
-        } catch (IOException e) {
-            e.printStackTrace();
-            fail("Deserialization failed");
-        }
 
         /* Those fields should be deserialized from JSON though */
-        secretJson = "{\"secret_id\":\"abc123\",\"metadata\":{\"number\":1337,\"foo\":\"bar\"}," +
+        String secretJson4 = "{\"secret_id\":\"abc123\",\"metadata\":{\"number\":1337,\"foo\":\"bar\"}," +
                 "\"cidr_list\":[\"203.0.113.0/24\",\"198.51.100.0/24\"],\"secret_id_accessor\":\"TEST_ACCESSOR\"," +
                 "\"creation_time\":\"TEST_CREATION\",\"expiration_time\":\"TEST_EXPIRATION\"," +
                 "\"last_updated_time\":\"TEST_LASTUPDATE\",\"secret_id_num_uses\":678,\"secret_id_ttl\":12345}";
-        try {
+        secret2 = assertDoesNotThrow(() -> mapper.readValue(secretJson4, AppRoleSecret.class), "Deserialization failed");
-            secret2 = mapper.readValue(secretJson, AppRoleSecret.class);
+        assertThat(secret2.getAccessor(), is("TEST_ACCESSOR"));
-            assertThat(secret2.getAccessor(), is("TEST_ACCESSOR"));
+        assertThat(secret2.getCreationTime(), is("TEST_CREATION"));
-            assertThat(secret2.getCreationTime(), is("TEST_CREATION"));
+        assertThat(secret2.getExpirationTime(), is("TEST_EXPIRATION"));
-            assertThat(secret2.getExpirationTime(), is("TEST_EXPIRATION"));
+        assertThat(secret2.getLastUpdatedTime(), is("TEST_LASTUPDATE"));
-            assertThat(secret2.getLastUpdatedTime(), is("TEST_LASTUPDATE"));
+        assertThat(secret2.getNumUses(), is(678));
-            assertThat(secret2.getNumUses(), is(678));
+        assertThat(secret2.getTtl(), is(12345));
-            assertThat(secret2.getTtl(), is(12345));
-        } catch (IOException e) {
-            e.printStackTrace();
-            fail("Deserialization failed");
-        }
 
     }
 

src/test/java/de/stklcode/jvault/connector/model/AuthBackendTest.java

@@ -27,13 +27,13 @@ import static org.hamcrest.Matchers.is;
  * @author Stefan Kalscheuer
  * @since 0.4.0
  */
-public class AuthBackendTest {
+class AuthBackendTest {
 
     /**
      * Test forType() method.
      */
     @Test
-    public void forTypeTest() {
+    void forTypeTest() {
         assertThat(AuthBackend.forType("token"), is(AuthBackend.TOKEN));
         assertThat(AuthBackend.forType("app-id"), is(AuthBackend.APPID));
         assertThat(AuthBackend.forType("userpass"), is(AuthBackend.USERPASS));

src/test/java/de/stklcode/jvault/connector/model/TokenBuilderTest.java

@@ -35,7 +35,7 @@ import static org.hamcrest.Matchers.*;
  * @author Stefan Kalscheuer
  * @since 0.4.0
  */
-public class TokenBuilderTest {
+class TokenBuilderTest {
     private static final String ID = "test-id";
     private static final String DISPLAY_NAME = "display-name";
     private static final Boolean NO_PARENT = false;
@@ -59,7 +59,7 @@ public class TokenBuilderTest {
     private static final String JSON_FULL = "{\"id\":\"test-id\",\"type\":\"service\",\"display_name\":\"display-name\",\"no_parent\":false,\"no_default_policy\":false,\"ttl\":123,\"explicit_max_ttl\":456,\"num_uses\":4,\"policies\":[\"policy\"],\"meta\":{\"key\":\"value\"},\"renewable\":true,\"period\":3600,\"entity_alias\":\"alias-value\"}";
 
     @BeforeAll
-    public static void init() {
+    static void init() {
         POLICIES.add(POLICY);
         META.put(META_KEY, META_VALUE);
     }
@@ -68,7 +68,7 @@ public class TokenBuilderTest {
      * Build token without any parameters.
      */
     @Test
-    public void buildDefaultTest() throws JsonProcessingException {
+    void buildDefaultTest() throws JsonProcessingException {
         Token token = Token.builder().build();
         assertThat(token.getId(), is(nullValue()));
         assertThat(token.getType(), is(nullValue()));
@@ -92,7 +92,7 @@ public class TokenBuilderTest {
      * Build token without any parameters.
      */
     @Test
-    public void legacyBuildDefaultTest() throws JsonProcessingException {
+    void legacyBuildDefaultTest() throws JsonProcessingException {
         Token token = new TokenBuilder().build();
         assertThat(token.getId(), is(nullValue()));
         assertThat(token.getType(), is(nullValue()));
@@ -113,7 +113,7 @@ public class TokenBuilderTest {
      * Build token without all parameters set.
      */
     @Test
-    public void buildFullTest() throws JsonProcessingException {
+    void buildFullTest() throws JsonProcessingException {
         Token token = Token.builder()
                 .withId(ID)
                 .withType(Token.Type.SERVICE)
@@ -150,7 +150,7 @@ public class TokenBuilderTest {
      * Build token without all parameters set.
      */
     @Test
-    public void legacyBuildFullTest() throws JsonProcessingException {
+    void legacyBuildFullTest() throws JsonProcessingException {
         Token token = new TokenBuilder()
                 .withId(ID)
                 .withType(Token.Type.SERVICE)
@@ -182,7 +182,7 @@ public class TokenBuilderTest {
      * Test convenience methods
      */
     @Test
-    public void convenienceMethodsTest() {
+    void convenienceMethodsTest() {
         /* Parent */
         Token token = Token.builder().asOrphan().build();
         assertThat(token.getNoParent(), is(true));
@@ -230,7 +230,7 @@ public class TokenBuilderTest {
      * Test convenience methods
      */
     @Test
-    public void legacyConvenienceMethodsTest() {
+    void legacyConvenienceMethodsTest() {
         /* Parent */
         Token token = new TokenBuilder().asOrphan().build();
         assertThat(token.getNoParent(), is(true));

src/test/java/de/stklcode/jvault/connector/model/TokenRoleBuilderTest.java

@@ -32,7 +32,7 @@ import static org.hamcrest.Matchers.*;
  * @author Stefan Kalscheuer
  * @since 0.9
  */
-public class TokenRoleBuilderTest {
+class TokenRoleBuilderTest {
     private static final String NAME = "test-role";
     private static final String ALLOWED_POLICY_1 = "apol-1";
     private static final String ALLOWED_POLICY_2 = "apol-2";
@@ -78,7 +78,7 @@ public class TokenRoleBuilderTest {
      * Build token without any parameters.
      */
     @Test
-    public void buildDefaultTest() throws JsonProcessingException {
+    void buildDefaultTest() throws JsonProcessingException {
         TokenRole role = TokenRole.builder().build();
         assertThat(role.getAllowedPolicies(), is(nullValue()));
         assertThat(role.getDisallowedPolicies(), is(nullValue()));
@@ -100,7 +100,7 @@ public class TokenRoleBuilderTest {
      * Build token without all parameters NULL.
      */
     @Test
-    public void buildNullTest() throws JsonProcessingException {
+    void buildNullTest() throws JsonProcessingException {
         TokenRole role = TokenRole.builder()
                 .forName(null)
                 .withAllowedPolicies(null)
@@ -141,7 +141,7 @@ public class TokenRoleBuilderTest {
      * Build token without all parameters set.
      */
     @Test
-    public void buildFullTest() throws JsonProcessingException {
+    void buildFullTest() throws JsonProcessingException {
         TokenRole role = TokenRole.builder()
                 .forName(NAME)
                 .withAllowedPolicies(ALLOWED_POLICIES)

src/test/java/de/stklcode/jvault/connector/model/response/AppRoleResponseTest.java

@@ -21,13 +21,13 @@ import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import de.stklcode.jvault.connector.model.AppRole;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit Test for {@link AppRoleResponse} model.
@@ -35,7 +35,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.6.2
  */
-public class AppRoleResponseTest {
+class AppRoleResponseTest {
     private static final Integer ROLE_TOKEN_TTL = 1200;
     private static final Integer ROLE_TOKEN_MAX_TTL = 1800;
     private static final Integer ROLE_SECRET_TTL = 600;
@@ -75,46 +75,44 @@ public class AppRoleResponseTest {
      * Test getter, setter and get-methods for response data.
      */
     @Test
-    public void getDataRoundtrip() {
+    void getDataRoundtrip() {
         // Create empty Object.
         AppRoleResponse res = new AppRoleResponse();
         assertThat("Initial data should be empty", res.getRole(), is(nullValue()));
 
         // Parsing invalid auth data map should fail.
-        try {
+        assertThrows(
-            res.setData(INVALID_DATA);
+                InvalidResponseException.class,
-            fail("Parsing invalid data succeeded");
+                () -> res.setData(INVALID_DATA),
-        } catch (Exception e) {
+                "Parsing invalid data succeeded"
-            assertThat(e, is(instanceOf(InvalidResponseException.class)));
+        );
-        }
     }
 
     /**
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        AppRoleResponse res = assertDoesNotThrow(
-            AppRoleResponse res = new ObjectMapper().readValue(RES_JSON, AppRoleResponse.class);
+                () -> new ObjectMapper().readValue(RES_JSON, AppRoleResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "AuthResponse deserialization failed."
-            // Extract role data.
+        );
-            AppRole role = res.getRole();
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Role data is NULL", role, is(notNullValue()));
+        // Extract role data.
-            assertThat("Incorrect token TTL", role.getTokenTtl(), is(ROLE_TOKEN_TTL));
+        AppRole role = res.getRole();
-            assertThat("Incorrect token max TTL", role.getTokenMaxTtl(), is(ROLE_TOKEN_MAX_TTL));
+        assertThat("Role data is NULL", role, is(notNullValue()));
-            assertThat("Incorrect secret ID TTL", role.getSecretIdTtl(), is(ROLE_SECRET_TTL));
+        assertThat("Incorrect token TTL", role.getTokenTtl(), is(ROLE_TOKEN_TTL));
-            assertThat("Incorrect secret ID umber of uses", role.getSecretIdNumUses(), is(ROLE_SECRET_NUM_USES));
+        assertThat("Incorrect token max TTL", role.getTokenMaxTtl(), is(ROLE_TOKEN_MAX_TTL));
-            assertThat("Incorrect number of policies", role.getTokenPolicies(), hasSize(1));
+        assertThat("Incorrect secret ID TTL", role.getSecretIdTtl(), is(ROLE_SECRET_TTL));
-            assertThat("Incorrect role policies", role.getTokenPolicies(), contains(ROLE_POLICY));
+        assertThat("Incorrect secret ID umber of uses", role.getSecretIdNumUses(), is(ROLE_SECRET_NUM_USES));
-            assertThat("Incorrect number of policies", role.getPolicies(), hasSize(1));
+        assertThat("Incorrect number of policies", role.getTokenPolicies(), hasSize(1));
-            assertThat("Incorrect role policies", role.getPolicies(), contains(ROLE_POLICY));
+        assertThat("Incorrect role policies", role.getTokenPolicies(), contains(ROLE_POLICY));
-            assertThat("Incorrect role period", role.getTokenPeriod(), is(ROLE_PERIOD));
+        assertThat("Incorrect number of policies", role.getPolicies(), hasSize(1));
-            assertThat("Incorrect role period", role.getPeriod(), is(ROLE_PERIOD));
+        assertThat("Incorrect role policies", role.getPolicies(), contains(ROLE_POLICY));
-            assertThat("Incorrect role bind secret ID flag", role.getBindSecretId(), is(ROLE_BIND_SECRET));
+        assertThat("Incorrect role period", role.getTokenPeriod(), is(ROLE_PERIOD));
-            assertThat("Incorrect bound CIDR list", role.getTokenBoundCidrs(), is(nullValue()));
+        assertThat("Incorrect role period", role.getPeriod(), is(ROLE_PERIOD));
-            assertThat("Incorrect bound CIDR list string", role.getTokenBoundCidrsString(), is(emptyString()));
+        assertThat("Incorrect role bind secret ID flag", role.getBindSecretId(), is(ROLE_BIND_SECRET));
-        } catch (IOException e) {
+        assertThat("Incorrect bound CIDR list", role.getTokenBoundCidrs(), is(nullValue()));
-            fail("AuthResponse deserialization failed: " + e.getMessage());
+        assertThat("Incorrect bound CIDR list string", role.getTokenBoundCidrsString(), is(emptyString()));
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/model/response/AuthMethodsResponseTest.java

@@ -22,13 +22,13 @@ import de.stklcode.jvault.connector.model.AuthBackend;
 import de.stklcode.jvault.connector.model.response.embedded.AuthMethod;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit Test for {@link AuthMethodsResponse} model.
@@ -36,7 +36,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.6.2
  */
-public class AuthMethodsResponseTest {
+class AuthMethodsResponseTest {
     private static final String GH_PATH = "github/";
     private static final String GH_TYPE = "github";
     private static final String GH_DESCR = "GitHub auth";
@@ -73,53 +73,51 @@ public class AuthMethodsResponseTest {
      * Test getter, setter and get-methods for response data.
      */
     @Test
-    public void getDataRoundtrip() {
+    void getDataRoundtrip() {
         // Create empty Object.
         AuthMethodsResponse res = new AuthMethodsResponse();
         assertThat("Initial method map should be empty", res.getSupportedMethods(), is(anEmptyMap()));
 
         // Parsing invalid data map should fail.
-        try {
+        assertThrows(
-            res.setData(INVALID_DATA);
+                InvalidResponseException.class,
-            fail("Parsing invalid data succeeded");
+                () -> res.setData(INVALID_DATA),
-        } catch (Exception e) {
+                "Parsing invalid data succeeded"
-            assertThat(e, is(instanceOf(InvalidResponseException.class)));
+        );
-        }
     }
 
     /**
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        AuthMethodsResponse res = assertDoesNotThrow(
-            AuthMethodsResponse res = new ObjectMapper().readValue(RES_JSON, AuthMethodsResponse.class);
+                () -> new ObjectMapper().readValue(RES_JSON, AuthMethodsResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "AuthResponse deserialization failed"
-            // Extract auth data.
+        );
-            Map<String, AuthMethod> supported = res.getSupportedMethods();
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Auth data is NULL", supported, is(notNullValue()));
+        // Extract auth data.
-            assertThat("Incorrect number of supported methods", supported.entrySet(), hasSize(2));
+        Map<String, AuthMethod> supported = res.getSupportedMethods();
-            assertThat("Incorrect method paths", supported.keySet(), containsInAnyOrder(GH_PATH, TK_PATH));
+        assertThat("Auth data is NULL", supported, is(notNullValue()));
+        assertThat("Incorrect number of supported methods", supported.entrySet(), hasSize(2));
+        assertThat("Incorrect method paths", supported.keySet(), containsInAnyOrder(GH_PATH, TK_PATH));
 
-            // Verify first method.
+        // Verify first method.
-            AuthMethod method = supported.get(GH_PATH);
+        AuthMethod method = supported.get(GH_PATH);
-            assertThat("Incorrect raw type for GitHub", method.getRawType(), is(GH_TYPE));
+        assertThat("Incorrect raw type for GitHub", method.getRawType(), is(GH_TYPE));
-            assertThat("Incorrect parsed type for GitHub", method.getType(), is(AuthBackend.GITHUB));
+        assertThat("Incorrect parsed type for GitHub", method.getType(), is(AuthBackend.GITHUB));
-            assertThat("Incorrect description for GitHub", method.getDescription(), is(GH_DESCR));
+        assertThat("Incorrect description for GitHub", method.getDescription(), is(GH_DESCR));
-            assertThat("Unexpected config for GitHub", method.getConfig(), is(nullValue()));
+        assertThat("Unexpected config for GitHub", method.getConfig(), is(nullValue()));
 
-            // Verify first method.
+        // Verify first method.
-            method = supported.get(TK_PATH);
+        method = supported.get(TK_PATH);
-            assertThat("Incorrect raw type for Token", method.getRawType(), is(TK_TYPE));
+        assertThat("Incorrect raw type for Token", method.getRawType(), is(TK_TYPE));
-            assertThat("Incorrect parsed type for Token", method.getType(), is(AuthBackend.TOKEN));
+        assertThat("Incorrect parsed type for Token", method.getType(), is(AuthBackend.TOKEN));
-            assertThat("Incorrect description for Token", method.getDescription(), is(TK_DESCR));
+        assertThat("Incorrect description for Token", method.getDescription(), is(TK_DESCR));
-            assertThat("Missing config for Token", method.getConfig(), is(notNullValue()));
+        assertThat("Missing config for Token", method.getConfig(), is(notNullValue()));
-            assertThat("Unexpected config size for Token", method.getConfig().keySet(), hasSize(2));
+        assertThat("Unexpected config size for Token", method.getConfig().keySet(), hasSize(2));
-            assertThat("Incorrect lease TTL config", method.getConfig().get("default_lease_ttl"), is(TK_LEASE_TTL.toString()));
+        assertThat("Incorrect lease TTL config", method.getConfig().get("default_lease_ttl"), is(TK_LEASE_TTL.toString()));
-            assertThat("Incorrect max lease TTL config", method.getConfig().get("max_lease_ttl"), is(TK_MAX_LEASE_TTL.toString()));
+        assertThat("Incorrect max lease TTL config", method.getConfig().get("max_lease_ttl"), is(TK_MAX_LEASE_TTL.toString()));
-        } catch (IOException e) {
-            fail("AuthResponse deserialization failed: " + e.getMessage());
-        }
     }
 
     private static class Dummy {

src/test/java/de/stklcode/jvault/connector/model/response/AuthResponseTest.java

@@ -21,13 +21,13 @@ import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import de.stklcode.jvault.connector.model.response.embedded.AuthData;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit Test for {@link AuthResponse} model.
@@ -35,7 +35,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.6.2
  */
-public class AuthResponseTest {
+class AuthResponseTest {
     private static final String AUTH_ACCESSOR = "2c84f488-2133-4ced-87b0-570f93a76830";
     private static final String AUTH_CLIENT_TOKEN = "ABCD";
     private static final String AUTH_POLICY_1 = "web";
@@ -81,18 +81,17 @@ public class AuthResponseTest {
      * Test getter, setter and get-methods for response data.
      */
     @Test
-    public void getDataRoundtrip() {
+    void getDataRoundtrip() {
         // Create empty Object.
         AuthResponse res = new AuthResponse();
         assertThat("Initial data should be empty", res.getData(), is(nullValue()));
 
         // Parsing invalid auth data map should fail.
-        try {
+        assertThrows(
-            res.setAuth(INVALID_AUTH_DATA);
+                InvalidResponseException.class,
-            fail("Parsing invalid auth data succeeded");
+                () -> res.setAuth(INVALID_AUTH_DATA),
-        } catch (Exception e) {
+                "Parsing invalid auth data succeeded"
-            assertThat(e, is(instanceOf(InvalidResponseException.class)));
+        );
-        }
 
         // Data method should be agnostic.
         res.setData(INVALID_AUTH_DATA);
@@ -103,9 +102,11 @@ public class AuthResponseTest {
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+            AuthResponse res = assertDoesNotThrow(
-            AuthResponse res = new ObjectMapper().readValue(RES_JSON, AuthResponse.class);
+                    () -> new ObjectMapper().readValue(RES_JSON, AuthResponse.class),
+                    "AuthResponse deserialization failed."
+            );
             assertThat("Parsed response is NULL", res, is(notNullValue()));
             // Extract auth data.
             AuthData data = res.getAuth();
@@ -123,9 +124,5 @@ public class AuthResponseTest {
             assertThat("Incorrect token policies", data.getTokenPolicies(), containsInRelativeOrder(AUTH_POLICY_2, AUTH_POLICY_1));
             assertThat("Incorrect auth metadata size", data.getMetadata().entrySet(), hasSize(1));
             assertThat("Incorrect auth metadata", data.getMetadata().get(AUTH_META_KEY), is(AUTH_META_VALUE));
-
-        } catch (IOException e) {
-            fail("AuthResponse deserialization failed: " + e.getMessage());
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/model/response/CredentialsResponseTest.java

@@ -35,7 +35,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.8
  */
-public class CredentialsResponseTest {
+class CredentialsResponseTest {
     private static final Map<String, Object> DATA = new HashMap<>();
     private static final String VAL_USER = "testUserName";
     private static final String VAL_PASS = "5up3r5ecr3tP455";
@@ -52,7 +52,7 @@ public class CredentialsResponseTest {
      */
     @Test
     @SuppressWarnings("unchecked")
-    public void getCredentialsTest() throws InvalidResponseException {
+    void getCredentialsTest() throws InvalidResponseException {
         // Create empty Object.
         CredentialsResponse res = new CredentialsResponse();
         assertThat("Username not present in data map should not return anything", res.getUsername(), is(nullValue()));

src/test/java/de/stklcode/jvault/connector/model/response/HealthResponseTest.java

@@ -19,12 +19,10 @@ package de.stklcode.jvault.connector.model.response;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 /**
  * JUnit Test for {@link AuthResponse} model.
@@ -32,7 +30,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.7.0
  */
-public class HealthResponseTest {
+class HealthResponseTest {
     private static final String CLUSTER_ID = "c9abceea-4f46-4dab-a688-5ce55f89e228";
     private static final String CLUSTER_NAME = "vault-cluster-5515c810";
     private static final String VERSION = "0.9.2";
@@ -56,26 +54,26 @@ public class HealthResponseTest {
             "  \"replication_dr_mode\": \"" + REPL_DR_MODE + "\",\n" +
             "  \"performance_standby\": " + PERF_STANDBY + "\n" +
             "}";
+
     /**
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        HealthResponse res = assertDoesNotThrow(
-            HealthResponse res = new ObjectMapper().readValue(RES_JSON, HealthResponse.class);
+                () -> new ObjectMapper().readValue(RES_JSON, HealthResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "Health deserialization failed."
-            assertThat("Incorrect cluster ID", res.getClusterID(), is(CLUSTER_ID));
+        );
-            assertThat("Incorrect cluster name", res.getClusterName(), is(CLUSTER_NAME));
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Incorrect version", res.getVersion(), is(VERSION));
+        assertThat("Incorrect cluster ID", res.getClusterID(), is(CLUSTER_ID));
-            assertThat("Incorrect server time", res.getServerTimeUTC(), is(SERVER_TIME_UTC));
+        assertThat("Incorrect cluster name", res.getClusterName(), is(CLUSTER_NAME));
-            assertThat("Incorrect standby state", res.isStandby(), is(STANDBY));
+        assertThat("Incorrect version", res.getVersion(), is(VERSION));
-            assertThat("Incorrect seal state", res.isSealed(), is(SEALED));
+        assertThat("Incorrect server time", res.getServerTimeUTC(), is(SERVER_TIME_UTC));
-            assertThat("Incorrect initialization state", res.isInitialized(), is(INITIALIZED));
+        assertThat("Incorrect standby state", res.isStandby(), is(STANDBY));
-            assertThat("Incorrect performance standby state", res.isPerformanceStandby(), is(PERF_STANDBY));
+        assertThat("Incorrect seal state", res.isSealed(), is(SEALED));
-            assertThat("Incorrect replication perf mode", res.getReplicationPerfMode(), is(REPL_PERF_MODE));
+        assertThat("Incorrect initialization state", res.isInitialized(), is(INITIALIZED));
-            assertThat("Incorrect replication DR mode", res.getReplicationDrMode(), is(REPL_DR_MODE));
+        assertThat("Incorrect performance standby state", res.isPerformanceStandby(), is(PERF_STANDBY));
-        } catch (IOException e) {
+        assertThat("Incorrect replication perf mode", res.getReplicationPerfMode(), is(REPL_PERF_MODE));
-            fail("Health deserialization failed: " + e.getMessage());
+        assertThat("Incorrect replication DR mode", res.getReplicationDrMode(), is(REPL_DR_MODE));
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/model/response/MetadataResponseTest.java

@@ -17,16 +17,12 @@
 package de.stklcode.jvault.connector.model.response;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
-import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-import java.util.List;
-import java.util.Map;
-
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.*;
+import static org.hamcrest.Matchers.is;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 /**
  * JUnit Test for {@link MetadataResponse} model.
@@ -34,7 +30,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.8
  */
-public class MetadataResponseTest {
+class MetadataResponseTest {
     private static final String V1_TIME = "2018-03-22T02:24:06.945319214Z";
     private static final String V3_TIME = "2018-03-22T02:36:43.986212308Z";
     private static final String V2_TIME = "2018-03-22T02:36:33.954880664Z";
@@ -73,28 +69,26 @@ public class MetadataResponseTest {
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        MetadataResponse res = assertDoesNotThrow(
-            MetadataResponse res = new ObjectMapper().readValue(META_JSON, MetadataResponse.class);
+                () -> new ObjectMapper().readValue(META_JSON, MetadataResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "MetadataResponse deserialization failed."
-            assertThat("Parsed metadata is NULL", res.getMetadata(), is(notNullValue()));
+        );
-            assertThat("Incorrect created time", res.getMetadata().getCreatedTimeString(), is(V1_TIME));
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Parting created time failed", res.getMetadata().getCreatedTime(), is(notNullValue()));
+        assertThat("Parsed metadata is NULL", res.getMetadata(), is(notNullValue()));
-            assertThat("Incorrect current version", res.getMetadata().getCurrentVersion(), is(CURRENT_VERSION));
+        assertThat("Incorrect created time", res.getMetadata().getCreatedTimeString(), is(V1_TIME));
-            assertThat("Incorrect max versions", res.getMetadata().getMaxVersions(), is(MAX_VERSIONS));
+        assertThat("Parting created time failed", res.getMetadata().getCreatedTime(), is(notNullValue()));
-            assertThat("Incorrect oldest version", res.getMetadata().getOldestVersion(), is(OLDEST_VERSION));
+        assertThat("Incorrect current version", res.getMetadata().getCurrentVersion(), is(CURRENT_VERSION));
-            assertThat("Incorrect updated time", res.getMetadata().getUpdatedTimeString(), is(V3_TIME));
+        assertThat("Incorrect max versions", res.getMetadata().getMaxVersions(), is(MAX_VERSIONS));
-            assertThat("Parting updated time failed", res.getMetadata().getUpdatedTime(), is(notNullValue()));
+        assertThat("Incorrect oldest version", res.getMetadata().getOldestVersion(), is(OLDEST_VERSION));
-            assertThat("Incorrect number of versions", res.getMetadata().getVersions().size(), is(3));
+        assertThat("Incorrect updated time", res.getMetadata().getUpdatedTimeString(), is(V3_TIME));
-            assertThat("Incorrect version 1 delete time", res.getMetadata().getVersions().get(1).getDeletionTimeString(), is(V2_TIME));
+        assertThat("Parting updated time failed", res.getMetadata().getUpdatedTime(), is(notNullValue()));
-            assertThat("Parsing version delete time failed", res.getMetadata().getVersions().get(1).getDeletionTime(), is(notNullValue()));
+        assertThat("Incorrect number of versions", res.getMetadata().getVersions().size(), is(3));
-            assertThat("Incorrect version 1 destroyed state", res.getMetadata().getVersions().get(1).isDestroyed(), is(true));
+        assertThat("Incorrect version 1 delete time", res.getMetadata().getVersions().get(1).getDeletionTimeString(), is(V2_TIME));
-            assertThat("Incorrect version 2 created time", res.getMetadata().getVersions().get(2).getCreatedTimeString(), is(V2_TIME));
+        assertThat("Parsing version delete time failed", res.getMetadata().getVersions().get(1).getDeletionTime(), is(notNullValue()));
-            assertThat("Parsing version created failed", res.getMetadata().getVersions().get(2).getCreatedTime(), is(notNullValue()));
+        assertThat("Incorrect version 1 destroyed state", res.getMetadata().getVersions().get(1).isDestroyed(), is(true));
-            assertThat("Incorrect version 3 destroyed state", res.getMetadata().getVersions().get(3).isDestroyed(), is(false));
+        assertThat("Incorrect version 2 created time", res.getMetadata().getVersions().get(2).getCreatedTimeString(), is(V2_TIME));
-
+        assertThat("Parsing version created failed", res.getMetadata().getVersions().get(2).getCreatedTime(), is(notNullValue()));
-        } catch (IOException e) {
+        assertThat("Incorrect version 3 destroyed state", res.getMetadata().getVersions().get(3).isDestroyed(), is(false));
-            fail("MetadataResponse deserialization failed: " + e.getMessage());
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/model/response/SealResponseTest.java

@@ -19,11 +19,9 @@ package de.stklcode.jvault.connector.model.response;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 /**
  * JUnit Test for {@link SealResponse} model.
@@ -31,7 +29,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.8
  */
-public class SealResponseTest {
+class SealResponseTest {
     private static final String TYPE = "shamir";
     private static final Integer THRESHOLD = 3;
     private static final Integer SHARES = 5;
@@ -70,43 +68,41 @@ public class SealResponseTest {
      * Test creation from JSON value as returned by Vault when sealed (JSON example close to Vault documentation).
      */
     @Test
-    public void jsonRoundtripSealed() {
+    void jsonRoundtripSealed() {
         // First test sealed Vault's response.
-        try {
+        SealResponse res = assertDoesNotThrow(
-            SealResponse res = new ObjectMapper().readValue(RES_SEALED, SealResponse.class);
+                () -> new ObjectMapper().readValue(RES_SEALED, SealResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "TokenResponse deserialization failed."
-            assertThat("Incorrect seal type", res.getType(), is(TYPE));
+        );
-            assertThat("Incorrect seal status", res.isSealed(), is(true));
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Incorrect initialization status", res.isInitialized(), is(true));
+        assertThat("Incorrect seal type", res.getType(), is(TYPE));
-            assertThat("Incorrect threshold", res.getThreshold(), is(THRESHOLD));
+        assertThat("Incorrect seal status", res.isSealed(), is(true));
-            assertThat("Incorrect number of shares", res.getNumberOfShares(), is(SHARES));
+        assertThat("Incorrect initialization status", res.isInitialized(), is(true));
-            assertThat("Incorrect progress", res.getProgress(), is(PROGRESS_SEALED));
+        assertThat("Incorrect threshold", res.getThreshold(), is(THRESHOLD));
-            assertThat("Nonce not empty", res.getNonce(), is(""));
+        assertThat("Incorrect number of shares", res.getNumberOfShares(), is(SHARES));
-            assertThat("Incorrect version", res.getVersion(), is(VERSION));
+        assertThat("Incorrect progress", res.getProgress(), is(PROGRESS_SEALED));
-            // And the fields, that should not be filled.
+        assertThat("Nonce not empty", res.getNonce(), is(""));
-            assertThat("Cluster name should not be populated", res.getClusterName(), is(nullValue()));
+        assertThat("Incorrect version", res.getVersion(), is(VERSION));
-            assertThat("Cluster ID should not be populated", res.getClusterId(), is(nullValue()));
+        // And the fields, that should not be filled.
-        } catch (IOException e) {
+        assertThat("Cluster name should not be populated", res.getClusterName(), is(nullValue()));
-            fail("TokenResponse deserialization failed: " + e.getMessage());
+        assertThat("Cluster ID should not be populated", res.getClusterId(), is(nullValue()));
-        }
 
 
         // Not test unsealed Vault's response.
-        try {
+        res = assertDoesNotThrow(
-            SealResponse res = new ObjectMapper().readValue(RES_UNSEALED, SealResponse.class);
+                () -> new ObjectMapper().readValue(RES_UNSEALED, SealResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "TokenResponse deserialization failed."
-            assertThat("Incorrect seal type", res.getType(), is(TYPE));
+        );
-            assertThat("Incorrect seal status", res.isSealed(), is(false));
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Incorrect initialization status", res.isInitialized(), is(true));
+        assertThat("Incorrect seal type", res.getType(), is(TYPE));
-            assertThat("Incorrect threshold", res.getThreshold(), is(THRESHOLD));
+        assertThat("Incorrect seal status", res.isSealed(), is(false));
-            assertThat("Incorrect number of shares", res.getNumberOfShares(), is(SHARES));
+        assertThat("Incorrect initialization status", res.isInitialized(), is(true));
-            assertThat("Incorrect progress", res.getProgress(), is(PROGRESS_UNSEALED));
+        assertThat("Incorrect threshold", res.getThreshold(), is(THRESHOLD));
-            assertThat("Incorrect nonce", res.getNonce(), is(NONCE));
+        assertThat("Incorrect number of shares", res.getNumberOfShares(), is(SHARES));
-            assertThat("Incorrect version", res.getVersion(), is(VERSION));
+        assertThat("Incorrect progress", res.getProgress(), is(PROGRESS_UNSEALED));
-            assertThat("Incorrect cluster name", res.getClusterName(), is(CLUSTER_NAME));
+        assertThat("Incorrect nonce", res.getNonce(), is(NONCE));
-            assertThat("Incorrect cluster ID", res.getClusterId(), is(CLUSTER_ID));
+        assertThat("Incorrect version", res.getVersion(), is(VERSION));
-        } catch (IOException e) {
+        assertThat("Incorrect cluster name", res.getClusterName(), is(CLUSTER_NAME));
-            fail("TokenResponse deserialization failed: " + e.getMessage());
+        assertThat("Incorrect cluster ID", res.getClusterId(), is(CLUSTER_ID));
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/model/response/SecretListResponseTest.java

@@ -26,7 +26,7 @@ import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit Test for {@link SecretListResponse} model.
@@ -34,7 +34,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.8
  */
-public class SecretListResponseTest {
+class SecretListResponseTest {
     private static final Map<String, Object> DATA = new HashMap<>();
     private static final String KEY1 = "key1";
     private static final String KEY2 = "key-2";
@@ -50,20 +50,19 @@ public class SecretListResponseTest {
      * @throws InvalidResponseException Should not occur
      */
     @Test
-    public void getKeysTest() throws InvalidResponseException {
+    void getKeysTest() throws InvalidResponseException {
         // Create empty Object.
         SecretListResponse res = new SecretListResponse();
         assertThat("Keys should be null without initialization", res.getKeys(), is(nullValue()));
 
         // Provoke internal ClassCastException.
-        try {
+        Map<String, Object> invalidData = new HashMap<>();
-            Map<String, Object> invalidData = new HashMap<>();
+        invalidData.put("keys", "some string");
-            invalidData.put("keys", "some string");
+        assertThrows(
-            res.setData(invalidData);
+                InvalidResponseException.class,
-            fail("Setting incorrect class succeeded");
+                () -> res.setData(invalidData),
-        } catch (Exception e) {
+                "Setting incorrect class succeeded"
-            assertThat("Unexpected exception type", e, instanceOf(InvalidResponseException.class));
+        );
-        }
 
         // Fill correct data.
         res.setData(DATA);

src/test/java/de/stklcode/jvault/connector/model/response/SecretResponseTest.java

@@ -20,14 +20,14 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit Test for {@link SecretResponse} model.
@@ -35,7 +35,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.6.2
  */
-public class SecretResponseTest {
+class SecretResponseTest {
     private static final Map<String, Object> DATA = new HashMap<>();
     private static final String KEY_UNKNOWN = "unknown";
     private static final String KEY_STRING = "test1";
@@ -120,7 +120,7 @@ public class SecretResponseTest {
      */
     @Test
     @SuppressWarnings("unchecked")
-    public void getDataRoundtrip() throws InvalidResponseException {
+    void getDataRoundtrip() throws InvalidResponseException {
         // Create empty Object.
         SecretResponse res = new SecretResponse();
         assertThat("Initial data should be Map", res.getData(), is(instanceOf(Map.class)));
@@ -137,61 +137,58 @@ public class SecretResponseTest {
         assertThat("Non-Null returned on unknown key", res.get(KEY_UNKNOWN), is(nullValue()));
 
         // Try explicit JSON conversion.
-        final List list = res.get(KEY_LIST, List.class);
+        final List<?> list = res.get(KEY_LIST, List.class);
         assertThat("JSON parsing of list failed", list, is(notNullValue()));
         assertThat("JSON parsing of list returned incorrect size", list.size(), is(2));
-        assertThat("JSON parsing of list returned incorrect elements", (List<Object>)list, contains("first", "second"));
+        assertThat("JSON parsing of list returned incorrect elements", list, contains("first", "second"));
         assertThat("Non-Null returned on unknown key", res.get(KEY_UNKNOWN, Object.class), is(nullValue()));
 
         // Requesting invalid class should result in Exception.
-        try {
+        assertThrows(
-            res.get(KEY_LIST, Double.class);
+                InvalidResponseException.class,
-            fail("JSON parsing to incorrect type succeeded.");
+                () -> res.get(KEY_LIST, Double.class),
-        } catch (Exception e) {
+                "JSON parsing to incorrect type succeeded."
-            assertThat(e, is(instanceOf(InvalidResponseException.class)));
+        );
-        }
     }
 
     /**
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        SecretResponse res = assertDoesNotThrow(
-            assertSecretData(new ObjectMapper().readValue(SECRET_JSON, SecretResponse.class));
+                () -> new ObjectMapper().readValue(SECRET_JSON, SecretResponse.class),
-        } catch (IOException e) {
+                "SecretResponse deserialization failed."
-            fail("SecretResponse deserialization failed: " + e.getMessage());
+        );
-        }
+        assertSecretData(res);
 
         // KV v2 secret.
-        try {
+        res = assertDoesNotThrow(
-            SecretResponse res = new ObjectMapper().readValue(SECRET_JSON_V2, SecretResponse.class);
+                () -> new ObjectMapper().readValue(SECRET_JSON_V2, SecretResponse.class),
-            assertSecretData(res);
+                "SecretResponse deserialization failed."
-            assertThat("SecretResponse does not contain metadata", res.getMetadata(), is(notNullValue()));
+        );
-            assertThat("Incorrect creation date string", res.getMetadata().getCreatedTimeString(), is(SECRET_META_CREATED));
+        assertSecretData(res);
-            assertThat("Creation date parsing failed", res.getMetadata().getCreatedTime(), is(notNullValue()));
+        assertThat("SecretResponse does not contain metadata", res.getMetadata(), is(notNullValue()));
-            assertThat("Incorrect deletion date string", res.getMetadata().getDeletionTimeString(), is(emptyString()));
+        assertThat("Incorrect creation date string", res.getMetadata().getCreatedTimeString(), is(SECRET_META_CREATED));
-            assertThat("Incorrect deletion date", res.getMetadata().getDeletionTime(), is(nullValue()));
+        assertThat("Creation date parsing failed", res.getMetadata().getCreatedTime(), is(notNullValue()));
-            assertThat("Secret destroyed when not expected", res.getMetadata().isDestroyed(), is(false));
+        assertThat("Incorrect deletion date string", res.getMetadata().getDeletionTimeString(), is(emptyString()));
-            assertThat("Incorrect secret version", res.getMetadata().getVersion(), is(1));
+        assertThat("Incorrect deletion date", res.getMetadata().getDeletionTime(), is(nullValue()));
-        } catch (IOException e) {
+        assertThat("Secret destroyed when not expected", res.getMetadata().isDestroyed(), is(false));
-            fail("SecretResponse deserialization failed: " + e.getMessage());
+        assertThat("Incorrect secret version", res.getMetadata().getVersion(), is(1));
-        }
 
         // Deleted KV v2 secret.
-        try {
+        res = assertDoesNotThrow(
-            SecretResponse res = new ObjectMapper().readValue(SECRET_JSON_V2_2, SecretResponse.class);
+                () -> new ObjectMapper().readValue(SECRET_JSON_V2_2, SecretResponse.class),
-            assertSecretData(res);
+                "SecretResponse deserialization failed."
-            assertThat("SecretResponse does not contain metadata", res.getMetadata(), is(notNullValue()));
+        );
-            assertThat("Incorrect creation date string", res.getMetadata().getCreatedTimeString(), is(SECRET_META_CREATED));
+        assertSecretData(res);
-            assertThat("Creation date parsing failed", res.getMetadata().getCreatedTime(), is(notNullValue()));
+        assertThat("SecretResponse does not contain metadata", res.getMetadata(), is(notNullValue()));
-            assertThat("Incorrect deletion date string", res.getMetadata().getDeletionTimeString(), is(SECRET_META_DELETED));
+        assertThat("Incorrect creation date string", res.getMetadata().getCreatedTimeString(), is(SECRET_META_CREATED));
-            assertThat("Incorrect deletion date", res.getMetadata().getDeletionTime(), is(notNullValue()));
+        assertThat("Creation date parsing failed", res.getMetadata().getCreatedTime(), is(notNullValue()));
-            assertThat("Secret destroyed when not expected", res.getMetadata().isDestroyed(), is(true));
+        assertThat("Incorrect deletion date string", res.getMetadata().getDeletionTimeString(), is(SECRET_META_DELETED));
-            assertThat("Incorrect secret version", res.getMetadata().getVersion(), is(2));
+        assertThat("Incorrect deletion date", res.getMetadata().getDeletionTime(), is(notNullValue()));
-        } catch (IOException e) {
+        assertThat("Secret destroyed when not expected", res.getMetadata().isDestroyed(), is(true));
-            fail("SecretResponse deserialization failed: " + e.getMessage());
+        assertThat("Incorrect secret version", res.getMetadata().getVersion(), is(2));
-        }
     }
 
     private void assertSecretData(SecretResponse res) {

src/test/java/de/stklcode/jvault/connector/model/response/SecretVersionResponseTest.java

@@ -19,12 +19,10 @@ package de.stklcode.jvault.connector.model.response;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 /**
  * JUnit Test for {@link SecretVersionResponse} model.
@@ -32,7 +30,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.8
  */
-public class SecretVersionResponseTest {
+class SecretVersionResponseTest {
     private static final String CREATION_TIME = "2018-03-22T02:24:06.945319214Z";
     private static final String DELETION_TIME = "2018-03-22T02:36:43.986212308Z";
     private static final Integer VERSION = 42;
@@ -50,17 +48,16 @@ public class SecretVersionResponseTest {
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        SecretVersionResponse res = assertDoesNotThrow(
-            SecretVersionResponse res = new ObjectMapper().readValue(META_JSON, SecretVersionResponse.class);
+                () -> new ObjectMapper().readValue(META_JSON, SecretVersionResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "SecretVersionResponse deserialization failed"
-            assertThat("Parsed metadata is NULL", res.getMetadata(), is(notNullValue()));
+        );
-            assertThat("Incorrect created time", res.getMetadata().getCreatedTimeString(), is(CREATION_TIME));
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Incorrect deletion time", res.getMetadata().getDeletionTimeString(), is(DELETION_TIME));
+        assertThat("Parsed metadata is NULL", res.getMetadata(), is(notNullValue()));
-            assertThat("Incorrect destroyed state", res.getMetadata().isDestroyed(), is(false));
+        assertThat("Incorrect created time", res.getMetadata().getCreatedTimeString(), is(CREATION_TIME));
-            assertThat("Incorrect version", res.getMetadata().getVersion(), is(VERSION));
+        assertThat("Incorrect deletion time", res.getMetadata().getDeletionTimeString(), is(DELETION_TIME));
-        } catch (IOException e) {
+        assertThat("Incorrect destroyed state", res.getMetadata().isDestroyed(), is(false));
-            fail("SecretVersionResponse deserialization failed: " + e.getMessage());
+        assertThat("Incorrect version", res.getMetadata().getVersion(), is(VERSION));
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/model/response/TokenResponseTest.java

@@ -21,14 +21,14 @@ import de.stklcode.jvault.connector.exception.InvalidResponseException;
 import de.stklcode.jvault.connector.model.response.embedded.TokenData;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.time.ZonedDateTime;
 import java.util.HashMap;
 import java.util.Map;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.*;
-import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * JUnit Test for {@link TokenResponse} model.
@@ -36,7 +36,7 @@ import static org.junit.jupiter.api.Assertions.fail;
  * @author Stefan Kalscheuer
  * @since 0.6.2
  */
-public class TokenResponseTest {
+class TokenResponseTest {
     private static final Integer TOKEN_CREATION_TIME = 1457533232;
     private static final Integer TOKEN_TTL = 2764800;
     private static final Integer TOKEN_EXPLICIT_MAX_TTL = 0;
@@ -101,57 +101,55 @@ public class TokenResponseTest {
      * Test getter, setter and get-methods for response data.
      */
     @Test
-    public void getDataRoundtrip() {
+    void getDataRoundtrip() {
         // Create empty Object.
         TokenResponse res = new TokenResponse();
         assertThat("Initial data should be empty", res.getData(), is(nullValue()));
 
         // Parsing invalid data map should fail.
-        try {
+        assertThrows(
-            res.setData(INVALID_TOKEN_DATA);
+                InvalidResponseException.class,
-            fail("Parsing invalid token data succeeded");
+                () -> res.setData(INVALID_TOKEN_DATA),
-        } catch (Exception e) {
+                "Parsing invalid token data succeeded"
-            assertThat(e, is(instanceOf(InvalidResponseException.class)));
+        );
-        }
     }
 
     /**
      * Test creation from JSON value as returned by Vault (JSON example copied from Vault documentation).
      */
     @Test
-    public void jsonRoundtrip() {
+    void jsonRoundtrip() {
-        try {
+        TokenResponse res = assertDoesNotThrow(
-            TokenResponse res = new ObjectMapper().readValue(RES_JSON, TokenResponse.class);
+                () -> new ObjectMapper().readValue(RES_JSON, TokenResponse.class),
-            assertThat("Parsed response is NULL", res, is(notNullValue()));
+                "TokenResponse deserialization failed."
-            assertThat("Incorrect lease duration", res.getLeaseDuration(), is(RES_LEASE_DURATION));
+        );
-            assertThat("Incorrect response renewable flag", res.isRenewable(), is(RES_RENEWABLE));
+        assertThat("Parsed response is NULL", res, is(notNullValue()));
-            assertThat("Incorrect response lease duration", res.getLeaseDuration(), is(RES_LEASE_DURATION));
+        assertThat("Incorrect lease duration", res.getLeaseDuration(), is(RES_LEASE_DURATION));
-            // Extract token data.
+        assertThat("Incorrect response renewable flag", res.isRenewable(), is(RES_RENEWABLE));
-            TokenData data = res.getData();
+        assertThat("Incorrect response lease duration", res.getLeaseDuration(), is(RES_LEASE_DURATION));
-            assertThat("Token data is NULL", data, is(notNullValue()));
+        // Extract token data.
-            assertThat("Incorrect token accessor", data.getAccessor(), is(TOKEN_ACCESSOR));
+        TokenData data = res.getData();
-            assertThat("Incorrect token creation time", data.getCreationTime(), is(TOKEN_CREATION_TIME));
+        assertThat("Token data is NULL", data, is(notNullValue()));
-            assertThat("Incorrect token creation TTL", data.getCreationTtl(), is(TOKEN_TTL));
+        assertThat("Incorrect token accessor", data.getAccessor(), is(TOKEN_ACCESSOR));
-            assertThat("Incorrect token display name", data.getName(), is(TOKEN_DISPLAY_NAME));
+        assertThat("Incorrect token creation time", data.getCreationTime(), is(TOKEN_CREATION_TIME));
-            assertThat("Incorrect token entity ID", data.getEntityId(), is(TOKEN_ENTITY_ID));
+        assertThat("Incorrect token creation TTL", data.getCreationTtl(), is(TOKEN_TTL));
-            assertThat("Incorrect token expire time", data.getExpireTimeString(), is(TOKEN_EXPIRE_TIME));
+        assertThat("Incorrect token display name", data.getName(), is(TOKEN_DISPLAY_NAME));
-            assertThat("Incorrect parsed token expire time", data.getExpireTime(), is(ZonedDateTime.parse(TOKEN_EXPIRE_TIME)));
+        assertThat("Incorrect token entity ID", data.getEntityId(), is(TOKEN_ENTITY_ID));
-            assertThat("Incorrect token explicit max TTL", data.getExplicitMaxTtl(), is(TOKEN_EXPLICIT_MAX_TTL));
+        assertThat("Incorrect token expire time", data.getExpireTimeString(), is(TOKEN_EXPIRE_TIME));
-            assertThat("Incorrect token ID", data.getId(), is(TOKEN_ID));
+        assertThat("Incorrect parsed token expire time", data.getExpireTime(), is(ZonedDateTime.parse(TOKEN_EXPIRE_TIME)));
-            assertThat("Incorrect token issue time", data.getIssueTimeString(), is(TOKEN_ISSUE_TIME));
+        assertThat("Incorrect token explicit max TTL", data.getExplicitMaxTtl(), is(TOKEN_EXPLICIT_MAX_TTL));
-            assertThat("Incorrect parsed token issue time", data.getIssueTime(), is(ZonedDateTime.parse(TOKEN_ISSUE_TIME)));
+        assertThat("Incorrect token ID", data.getId(), is(TOKEN_ID));
-            assertThat("Incorrect token metadata size", data.getMeta().entrySet(), hasSize(1));
+        assertThat("Incorrect token issue time", data.getIssueTimeString(), is(TOKEN_ISSUE_TIME));
-            assertThat("Incorrect token metadata", data.getMeta().get(TOKEN_META_KEY), is(TOKEN_META_VALUE));
+        assertThat("Incorrect parsed token issue time", data.getIssueTime(), is(ZonedDateTime.parse(TOKEN_ISSUE_TIME)));
-            assertThat("Incorrect token number of uses", data.getNumUses(), is(TOKEN_NUM_USES));
+        assertThat("Incorrect token metadata size", data.getMeta().entrySet(), hasSize(1));
-            assertThat("Incorrect token orphan flag", data.isOrphan(), is(TOKEN_ORPHAN));
+        assertThat("Incorrect token metadata", data.getMeta().get(TOKEN_META_KEY), is(TOKEN_META_VALUE));
-            assertThat("Incorrect token path", data.getPath(), is(TOKEN_PATH));
+        assertThat("Incorrect token number of uses", data.getNumUses(), is(TOKEN_NUM_USES));
-            assertThat("Incorrect number of token policies", data.getPolicies(), hasSize(2));
+        assertThat("Incorrect token orphan flag", data.isOrphan(), is(TOKEN_ORPHAN));
-            assertThat("Incorrect token policies", data.getPolicies(), contains(TOKEN_POLICY_1, TOKEN_POLICY_2));
+        assertThat("Incorrect token path", data.getPath(), is(TOKEN_PATH));
-            assertThat("Incorrect token renewable flag", data.isRenewable(), is(TOKEN_RENEWABLE));
+        assertThat("Incorrect number of token policies", data.getPolicies(), hasSize(2));
-            assertThat("Incorrect token TTL", data.getTtl(), is(RES_TTL));
+        assertThat("Incorrect token policies", data.getPolicies(), contains(TOKEN_POLICY_1, TOKEN_POLICY_2));
-            assertThat("Incorrect token type", data.getType(), is(TOKEN_TYPE));
+        assertThat("Incorrect token renewable flag", data.isRenewable(), is(TOKEN_RENEWABLE));
-        } catch (IOException e) {
+        assertThat("Incorrect token TTL", data.getTtl(), is(RES_TTL));
-            fail("TokenResponse deserialization failed: " + e.getMessage());
+        assertThat("Incorrect token type", data.getType(), is(TOKEN_TYPE));
-        }
     }
 }

src/test/java/de/stklcode/jvault/connector/test/EnvironmentMock.java

@@ -1,51 +0,0 @@
-/*
- * Copyright 2016-2021 Stefan Kalscheuer
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package de.stklcode.jvault.connector.test;
-
-import java.lang.reflect.Field;
-import java.util.Map;
-
-import static org.junit.jupiter.api.Assertions.fail;
-
-/**
- * Test helper to modify system environment.
- *
- * @author Stefan Kalscheuer
- */
-@SuppressWarnings("unchecked")
-public class EnvironmentMock {
-    private static Map<String, String> environment;
-
-    static {
-        try {
-            Map<String, String> originalEnv = System.getenv();
-            Field mapField = originalEnv.getClass().getDeclaredField("m");
-            mapField.setAccessible(true);
-            environment = (Map<String, String>) mapField.get(originalEnv);
-        } catch (NoSuchFieldException | IllegalAccessException | ClassCastException e) {
-            fail("Failed to intercept unmodifiable system environment");
-        }
-    }
-
-    public static void setenv(String key, String value) {
-        if (value != null) {
-            environment.put(key, value);
-        } else {
-            environment.remove(key);
-        }
-    }
-}