Various Java cleanups

src/main/java/io/strimzi/test/container/AuthenticationType.java

@@ -37,5 +37,5 @@ public enum AuthenticationType {
     /**
      * GSSAPI (Kerberos) authentication.
      */
-    GSSAPI;
+    GSSAPI
 }

src/main/java/io/strimzi/test/container/KafkaVersionService.java

@@ -85,7 +85,7 @@ protected static String strimziTestContainerImageName(String kafkaVersion) {
                 }
                 throw new UnknownKafkaVersionException("Doesn't know the specified Kafka version: " + kafkaVersion + ". " +
                     "The supported Kafka versions are: " +
-                    KafkaVersionService.getInstance().logicalKafkaVersionEntities.stream().map(KafkaVersion::getVersion).collect(Collectors.toList()).toString());
+                    KafkaVersionService.getInstance().logicalKafkaVersionEntities.stream().map(KafkaVersion::getVersion).collect(Collectors.toList()));
             }
         }
         return imageName;
@@ -197,7 +197,7 @@ public String toString() {
      */
     public KafkaVersion latestRelease() {
         // at least one release in the json schema is needed
-        if (this.logicalKafkaVersionEntities == null || this.logicalKafkaVersionEntities.size() < 1) {
+        if (this.logicalKafkaVersionEntities.isEmpty()) {
             throw new IllegalStateException("Wrong json schema! It must have at least one release");
         }
 
@@ -227,7 +227,7 @@ public KafkaVersion latestRelease() {
      *                                                     *
      * |    2.8.1   &lt;---&gt;     2.8.2  &lt;---&gt;   3.0.0  |
      * ============================================================
-     * Assuming that test container images `kafka_versions.yaml` has following content:
+     * Assuming that test container images `kafka_versions.yaml` has the following content:
      * {
      *   "version": 1,
      *   "kafkaVersions": {
@@ -239,7 +239,7 @@ public KafkaVersion latestRelease() {
      * @return LogicalKafkaVersion the previous minor release
      */
     public KafkaVersion previousMinor() {
-        if (this.logicalKafkaVersionEntities == null || this.logicalKafkaVersionEntities.size() < 1) {
+        if (this.logicalKafkaVersionEntities.isEmpty()) {
             throw new IllegalStateException("Wrong json schema! It must have at least one release");
         }
 

src/main/java/io/strimzi/test/container/StrimziKafkaCluster.java

@@ -41,17 +41,17 @@ public class StrimziKafkaCluster implements KafkaContainer {
     // instance attributes
     private final int brokersNum;
     private final int internalTopicReplicationFactor;
-    private Map<String, String> additionalKafkaConfiguration;
-    private ToxiproxyContainer proxyContainer;
-    private boolean enableSharedNetwork;
-    private String kafkaVersion;
-    private boolean enableKraft;
+    private final Map<String, String> additionalKafkaConfiguration;
+    private final ToxiproxyContainer proxyContainer;
+    private final boolean enableSharedNetwork;
+    private final String kafkaVersion;
+    private final boolean enableKraft;
 
     // not editable
     private final Network network;
     private StrimziZookeeperContainer zookeeper;
     private Collection<KafkaContainer> brokers;
-    private String clusterId;
+    private final String clusterId;
 
     private StrimziKafkaCluster(StrimziKafkaClusterBuilder builder) {
         this.brokersNum = builder.brokersNum;
@@ -267,7 +267,7 @@ public Collection<KafkaContainer> getBrokers() {
     @DoNotMutate
     public boolean hasKraftOrExternalZooKeeperConfigured() {
         KafkaContainer broker0 = brokers.iterator().next();
-        return broker0.hasKraftOrExternalZooKeeperConfigured() ? true : false;
+        return broker0.hasKraftOrExternalZooKeeperConfigured();
     }
 
     @Override
@@ -347,7 +347,7 @@ public void start() {
         }
 
         if (this.isZooKeeperBasedKafkaCluster()) {
-            Utils.waitFor("Kafka brokers nodes to be connected to the ZooKeeper", Duration.ofSeconds(1).toMillis(), Duration.ofMinutes(1).toMillis(),
+            Utils.waitFor("Kafka brokers nodes to be connected to the ZooKeeper", Duration.ofSeconds(1), Duration.ofMinutes(1),
                 () -> {
                     Container.ExecResult result;
                     try {
@@ -367,7 +367,7 @@ public void start() {
                 });
         } else if (this.isKraftKafkaCluster()) {
             // Readiness check for KRaft mode
-            Utils.waitFor("Kafka brokers to form a quorum", Duration.ofSeconds(1).toMillis(), Duration.ofMinutes(1).toMillis(),
+            Utils.waitFor("Kafka brokers to form a quorum", Duration.ofSeconds(1), Duration.ofMinutes(1),
                 () -> {
                     try {
                         for (KafkaContainer kafkaContainer : this.brokers) {

src/main/java/io/strimzi/test/container/Utils.java

@@ -11,6 +11,7 @@
 import java.net.ServerSocket;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.time.Duration;
 import java.util.Optional;
 import java.util.function.BooleanSupplier;
 
@@ -27,19 +28,19 @@ class Utils {
     private static final Logger LOGGER = LoggerFactory.getLogger(Utils.class);
 
     /**
-     * Poll the given {@code ready} function every {@code pollIntervalMs} milliseconds until it returns true,
-     * or throw a WaitException if it doesn't returns true within {@code timeoutMs} milliseconds.
+     * Poll the given {@code ready} function every {@code pollInterval} until it returns true,
+     * or throw a WaitException if it doesn't returns true within {@code timeout}.
      * @return The remaining time left until timeout occurs
      * (helpful if you have several calls which need to share a common timeout),
      *
      * @param description waiting for `description`
-     * @param pollIntervalMs poll interval in milliseconds
-     * @param timeoutMs timeout in milliseconds
+     * @param pollInterval poll interval
+     * @param timeout timeout
      * @param ready lambda predicate
      */
-    static long waitFor(String description, long pollIntervalMs, long timeoutMs, BooleanSupplier ready) {
+    static long waitFor(String description, Duration pollInterval, Duration timeout, BooleanSupplier ready) {
         LOGGER.debug("Waiting for {}", description);
-        long deadline = System.currentTimeMillis() + timeoutMs;
+        long deadline = System.currentTimeMillis() + timeout.toMillis();
         String exceptionMessage = null;
         int exceptionCount = 0;
         StringWriter stackTraceError = new StringWriter();
@@ -71,11 +72,11 @@ static long waitFor(String description, long pollIntervalMs, long timeoutMs, Boo
                         LOGGER.error(stackTraceError.toString());
                     }
                 }
-                WaitException waitException = new WaitException("Timeout after " + timeoutMs + " ms waiting for " + description);
+                WaitException waitException = new WaitException("Timeout after " + timeout.toMillis() + " ms waiting for " + description);
                 waitException.addSuppressed(waitException);
                 throw waitException;
             }
-            long sleepTime = Math.min(pollIntervalMs, timeLeft);
+            long sleepTime = Math.min(pollInterval.toMillis(), timeLeft);
             if (LOGGER.isTraceEnabled()) {
                 LOGGER.trace("{} not satisfied, will try again in {} ms ({}ms till timeout)", description, sleepTime, timeLeft);
             }

src/test/java/io/strimzi/test/container/StrimziKafkaClusterIT.java

@@ -6,7 +6,6 @@
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Collectors;
 
 import eu.rekawek.toxiproxy.Proxy;
 import org.apache.kafka.clients.admin.AdminClient;
@@ -111,7 +110,7 @@ void testStartClusterWithProxyContainer() {
             }
 
             assertThat(systemUnderTest.getBootstrapServers(),
-                is(bootstrapUrls.stream().collect(Collectors.joining(","))));
+                is(String.join(",", bootstrapUrls)));
         } finally {
             systemUnderTest.stop();
         }
@@ -173,7 +172,7 @@ private void verifyFunctionalityOfKafkaCluster() throws ExecutionException, Inte
 
             producer.send(new ProducerRecord<>(topicName, recordKey, recordValue)).get();
 
-            Utils.waitFor("Consumer records are present", Duration.ofSeconds(10).toMillis(), Duration.ofMinutes(2).toMillis(),
+            Utils.waitFor("Consumer records are present", Duration.ofSeconds(10), Duration.ofMinutes(2),
                 () -> {
                     ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
 

src/test/java/io/strimzi/test/container/StrimziKafkaContainerIT.java

@@ -72,7 +72,7 @@ void testStartContainerWithEmptyConfiguration(final String imageName) {
             systemUnderTest.start();
 
             assertThat(systemUnderTest.getBootstrapServers(), is("PLAINTEXT://"
-                    + systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                    + systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
         }
     }
 
@@ -123,7 +123,7 @@ void testStartContainerWithSSLBootstrapServers(final String imageName) {
         systemUnderTest.start();
 
         assertThat(systemUnderTest.getBootstrapServers(), is("SSL://"
-                + systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                + systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
     }
 
     @ParameterizedTest(name = "testStartContainerWithServerProperties-{0}")
@@ -140,7 +140,7 @@ void testStartContainerWithServerProperties(final String imageName) {
         assertThat(logsFromKafka, containsString("auto.create.topics.enable = false"));
 
         assertThat(systemUnderTest.getBootstrapServers(), is("PLAINTEXT://"
-                + systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                + systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
     }
 
     @Test
@@ -155,7 +155,7 @@ void testStartContainerWithStrimziKafkaImage() {
         systemUnderTest.start();
 
         assertThat(systemUnderTest.getBootstrapServers(), is("PLAINTEXT://"
-                + systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                + systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
 
         assertThat(systemUnderTest.getDockerImageName(), is(imageName));
 
@@ -172,7 +172,7 @@ void testStartContainerWithCustomImage() {
         systemUnderTest.start();
 
         assertThat(systemUnderTest.getBootstrapServers(), is("PLAINTEXT://"
-                + systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                + systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
 
         assertThat(systemUnderTest.getDockerImageName(), is(imageName));
     }
@@ -188,7 +188,7 @@ void testStartContainerWithCustomNetwork() {
         systemUnderTest.start();
 
         assertThat(systemUnderTest.getBootstrapServers(), is("PLAINTEXT://"
-                + systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                + systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
 
         assertThat(systemUnderTest.getNetwork().getId(), is(network.getId()));
     }
@@ -349,7 +349,7 @@ void testKafkaContainerFunctionality() {
 
                 producer.send(new ProducerRecord<>(topicName, recordKey, recordValue)).get();
 
-                Utils.waitFor("Consumer records are present", Duration.ofSeconds(10).toMillis(), Duration.ofMinutes(2).toMillis(),
+                Utils.waitFor("Consumer records are present", Duration.ofSeconds(10), Duration.ofMinutes(2),
                     () -> {
                         ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
 

src/test/java/io/strimzi/test/container/StrimziKafkaContainerMockTest.java

@@ -18,8 +18,8 @@
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertTrue;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class StrimziKafkaContainerMockTest {
 

src/test/java/io/strimzi/test/container/StrimziKafkaContainerTest.java

@@ -27,10 +27,10 @@
 import static org.hamcrest.CoreMatchers.nullValue;
 import static org.hamcrest.CoreMatchers.startsWith;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertTrue;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 class StrimziKafkaContainerTest {
 
@@ -358,8 +358,7 @@ void testConfigureOAuthBearer() {
         assertThat(properties.getProperty("sasl.mechanism.controller.protocol"), is("OAUTHBEARER"));
         assertThat(properties.getProperty("principal.builder.class"), is("io.strimzi.kafka.oauth.server.OAuthKafkaPrincipalBuilder"));
 
-        String expectedJaasConfig = String.format(
-            "org.apache.kafka.common.security.oauthbearer.OAuthBearerLoginModule required ;");
+        String expectedJaasConfig = "org.apache.kafka.common.security.oauthbearer.OAuthBearerLoginModule required ;";
 
         String listenerNameLowerCase = "plaintext";
 

src/test/java/io/strimzi/test/container/StrimziKafkaKRaftClusterIT.java

@@ -38,7 +38,6 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
-import java.util.stream.Collectors;
 
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.CoreMatchers.notNullValue;
@@ -128,7 +127,7 @@ void testStartClusterWithProxyContainer() {
             }
 
             assertThat(systemUnderTest.getBootstrapServers(),
-                is(bootstrapUrls.stream().collect(Collectors.joining(","))));
+                is(String.join(",", bootstrapUrls)));
         } finally {
             if (systemUnderTest != null) {
                 systemUnderTest.stop();
@@ -194,7 +193,7 @@ private void verifyFunctionalityOfKafkaCluster() throws ExecutionException, Inte
 
             producer.send(new ProducerRecord<>(topicName, recordKey, recordValue)).get();
 
-            Utils.waitFor("Consumer records are present", Duration.ofSeconds(10).toMillis(), Duration.ofMinutes(2).toMillis(),
+            Utils.waitFor("Consumer records are present", Duration.ofSeconds(10), Duration.ofMinutes(2),
                 () -> {
                     ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
 

src/test/java/io/strimzi/test/container/StrimziKafkaKraftContainerIT.java

@@ -69,7 +69,7 @@ void testStartContainerWithEmptyConfiguration(final String imageName, final Stri
             verify();
 
             assertThat(systemUnderTest.getBootstrapServers(), is("PLAINTEXT://" +
-                systemUnderTest.getContainerIpAddress() + ":" + systemUnderTest.getMappedPort(9092)));
+                systemUnderTest.getHost() + ":" + systemUnderTest.getMappedPort(9092)));
         } finally {
             systemUnderTest.stop();
         }