Fix JavaDocs and ALL Checkstyle rules

spring-kafka-test/src/main/java/org/springframework/kafka/test/hamcrest/KafkaMatchers.java

@@ -22,6 +22,7 @@
 import org.hamcrest.Matcher;
 
 /**
+ * The Hamcrest {@link Matcher}s utilities.
  *
  * @author Gary Russell
  *

spring-kafka-test/src/main/java/org/springframework/kafka/test/rule/KafkaEmbedded.java

@@ -63,6 +63,8 @@
 import scala.collection.Set;
 
 /**
+ * The {@link KafkaRule} implementation for the embedded Kafka Broker and Zookeeper.
+ *
  * @author Marius Bogoevici
  * @author Artem Bilan
  * @author Gary Russell

spring-kafka-test/src/main/java/org/springframework/kafka/test/utils/KafkaTestUtils.java

@@ -25,6 +25,8 @@
 import org.springframework.kafka.test.rule.KafkaEmbedded;
 
 /**
+ * The Kafka specific testing utilities.
+ *
  * @author Gary Russell
  *
  */

spring-kafka/src/main/java/org/springframework/kafka/annotation/KafkaListenerAnnotationBeanPostProcessor.java

@@ -73,6 +73,9 @@
  * factory or for fine-grained control over endpoints registration. See
  * {@link EnableKafka} Javadoc for complete usage details.
  *
+ * @param <K> the key type.
+ * @param <V> the value type.
+ *
  * @author Stephane Nicoll
  * @author Juergen Hoeller
  * @author Gary Russell
@@ -485,7 +488,8 @@ private Object resolveExpression(String value) {
 
 	/**
 	 * Resolve the specified value if possible.
-	 *
+	 * @param value the value to resolve
+	 * @return the resolved value
 	 * @see ConfigurableBeanFactory#resolveEmbeddedValue
 	 */
 	private String resolve(String value) {

spring-kafka/src/main/java/org/springframework/kafka/annotation/TopicPartition.java

@@ -31,13 +31,15 @@
 public @interface TopicPartition {
 
 	/**
+	 * The topic to listen on.
 	 * @return the topic to listen on. Property place holders
 	 * and SpEL expressions are supported, which must resolve
 	 * to a String.
 	 */
 	String topic();
 
 	/**
+	 * The partitions within the topic.
 	 * @return the partitions within the topic. Property place
 	 * holders and SpEL expressions are supported, which must
 	 * resolve to Integers (or Strings that can be parsed as

spring-kafka/src/main/java/org/springframework/kafka/config/AbstractKafkaListenerContainerFactory.java

@@ -27,6 +27,10 @@
 /**
  * Base {@link KafkaListenerContainerFactory} for Spring's base container implementation.
  *
+ * @param <C> the {@link AbstractMessageListenerContainer} implementation type.
+ * @param <K> the key type.
+ * @param <V> the value type.
+ *
  * @author Stephane Nicoll
  *
  * @see AbstractMessageListenerContainer
@@ -51,6 +55,7 @@ public abstract class AbstractKafkaListenerContainerFactory<C extends AbstractMe
 	private Long pollTimeout;
 
 	/**
+	 * Specify a {@link ConsumerFactory} to use.
 	 * @param consumerFactory The consumer factory.
 	 */
 	public void setConsumerFactory(ConsumerFactory<K, V> consumerFactory) {
@@ -62,6 +67,7 @@ public ConsumerFactory<K, V> getConsumerFactory() {
 	}
 
 	/**
+	 * Specify an {@link ErrorHandler} to use.
 	 * @param errorHandler The error handler.
 	 * @see AbstractMessageListenerContainer#setErrorHandler(ErrorHandler)
 	 */
@@ -70,6 +76,7 @@ public void setErrorHandler(ErrorHandler errorHandler) {
 	}
 
 	/**
+	 * Specify an {@link Executor} to use.
 	 * @param taskExecutor the {@link Executor} to use.
 	 * @see AbstractKafkaListenerContainerFactory#setTaskExecutor
 	 */
@@ -78,6 +85,7 @@ public void setTaskExecutor(Executor taskExecutor) {
 	}
 
 	/**
+	 * Specify an {@code autoStartup boolean} flag.
 	 * @param autoStartup true for auto startup.
 	 * @see AbstractMessageListenerContainer#setAutoStartup(boolean)
 	 */
@@ -86,6 +94,7 @@ public void setAutoStartup(Boolean autoStartup) {
 	}
 
 	/**
+	 * Specify a {@code phase} to use.
 	 * @param phase The phase.
 	 * @see AbstractMessageListenerContainer#setPhase(int)
 	 */
@@ -94,6 +103,7 @@ public void setPhase(int phase) {
 	}
 
 	/**
+	 * Specify an {@code ackCount} to use.
 	 * @param ackCount the ack count.
 	 * @see AbstractMessageListenerContainer#setAckCount(int)
 	 */
@@ -102,6 +112,7 @@ public void setAckCount(Integer ackCount) {
 	}
 
 	/**
+	 * Specify an {@link AckMode} to use.
 	 * @param ackMode the ack mode.
 	 * @see AbstractMessageListenerContainer#setAckMode(AckMode)
 	 */
@@ -110,6 +121,7 @@ public void setAckMode(AckMode ackMode) {
 	}
 
 	/**
+	 * Specify a {@code pollTimeout} to use.
 	 * @param pollTimeout the poll timeout
 	 * @see AbstractMessageListenerContainer#setPollTimeout(long)
 	 */

spring-kafka/src/main/java/org/springframework/kafka/config/AbstractKafkaListenerEndpoint.java

@@ -36,7 +36,10 @@
 import org.springframework.util.Assert;
 
 /**
- * Base model for a Kafka listener endpoint
+ * Base model for a Kafka listener endpoint.
+ *
+ * @param <K> the key type.
+ * @param <V> the value type.
  *
  * @author Stephane Nicoll
  * @author Gary Russell
@@ -95,8 +98,7 @@ public String getId() {
 	}
 
 	/**
-	 * Set the topics to use. Either these or 'topicPattern'
-	 * or 'topicPartitions'
+	 * Set the topics to use. Either these or 'topicPattern' or 'topicPartitions'
 	 * should be provided, but not a mixture.
 	 * @param topics to set.
 	 * @see #setTopicPartitions(TopicPartition...)
@@ -109,6 +111,7 @@ public void setTopics(String... topics) {
 	}
 
 	/**
+	 * Return the topics for this endpoint.
 	 * @return the topics for this endpoint.
 	 */
 	@Override
@@ -131,6 +134,7 @@ public void setTopicPartitions(TopicPartition... topicPartitions) {
 	}
 
 	/**
+	 * Return the topicPartitions for this endpoint.
 	 * @return the topicPartitions for this endpoint.
 	 */
 	@Override
@@ -150,6 +154,7 @@ public void setTopicPattern(Pattern topicPattern) {
 	}
 
 	/**
+	 * Return the topicPattern for this endpoint.
 	 * @return the topicPattern for this endpoint.
 	 */
 	@Override
@@ -207,6 +212,7 @@ private void setupMessageListener(MessageListenerContainer container) {
 	}
 
 	/**
+	 * Return a description for this endpoint.
 	 * @return a description for this endpoint.
 	 * <p>Available to subclasses, for inclusion in their {@code toString()} result.
 	 */

spring-kafka/src/main/java/org/springframework/kafka/config/KafkaListenerContainerFactory.java

@@ -16,13 +16,17 @@
 
 package org.springframework.kafka.config;
 
+import org.springframework.kafka.listener.AbstractMessageListenerContainer;
 import org.springframework.kafka.listener.MessageListenerContainer;
 
 /**
  * Factory of {@link MessageListenerContainer} based on a
  * {@link KafkaListenerEndpoint} definition.
  *
+ * @param <C> the {@link AbstractMessageListenerContainer} implementation type.
+ *
  * @author Stephane Nicoll
+ *
  * @see KafkaListenerEndpoint
  */
 public interface KafkaListenerContainerFactory<C extends MessageListenerContainer> {

spring-kafka/src/main/java/org/springframework/kafka/config/KafkaListenerEndpoint.java

@@ -34,6 +34,7 @@
 public interface KafkaListenerEndpoint {
 
 	/**
+	 * Return the id of this endpoint.
 	 * @return the id of this endpoint. The id can be further qualified
 	 * when the endpoint is resolved against its actual listener
 	 * container.
@@ -42,21 +43,25 @@ public interface KafkaListenerEndpoint {
 	String getId();
 
 	/**
+	 * Return the group of this endpoint or null if not in a group.
 	 * @return the group of this endpoint or null if not in a group.
 	 */
 	String getGroup();
 
 	/**
+	 * Return the topics for this endpoint.
 	 * @return the topics for this endpoint.
 	 */
 	Collection<String> getTopics();
 
 	/**
+	 * Return the topicPartitions for this endpoint.
 	 * @return the topicPartitions for this endpoint.
 	 */
 	Collection<TopicPartition> getTopicPartitions();
 
 	/**
+	 * Return the topicPattern for this endpoint.
 	 * @return the topicPattern for this endpoint.
 	 */
 	Pattern getTopicPattern();

spring-kafka/src/main/java/org/springframework/kafka/config/KafkaListenerEndpointRegistrar.java

@@ -63,6 +63,8 @@ public void setEndpointRegistry(KafkaListenerEndpointRegistry endpointRegistry)
 	}
 
 	/**
+	 * Return the {@link KafkaListenerEndpointRegistry} instance for this
+	 * registrar, may be {@code null}.
 	 * @return the {@link KafkaListenerEndpointRegistry} instance for this
 	 * registrar, may be {@code null}.
 	 */
@@ -84,6 +86,7 @@ public void setMessageHandlerMethodFactory(MessageHandlerMethodFactory kafkaHand
 	}
 
 	/**
+	 * Return the custom {@link MessageHandlerMethodFactory} to use, if any.
 	 * @return the custom {@link MessageHandlerMethodFactory} to use, if any.
 	 */
 	public MessageHandlerMethodFactory getMessageHandlerMethodFactory() {
@@ -201,7 +204,8 @@ private static final class KafkaListenerEndpointDescriptor {
 
 		private final KafkaListenerContainerFactory<?> containerFactory;
 
-		private KafkaListenerEndpointDescriptor(KafkaListenerEndpoint endpoint, KafkaListenerContainerFactory<?> containerFactory) {
+		private KafkaListenerEndpointDescriptor(KafkaListenerEndpoint endpoint,
+							KafkaListenerContainerFactory<?> containerFactory) {
 			this.endpoint = endpoint;
 			this.containerFactory = containerFactory;
 		}

spring-kafka/src/main/java/org/springframework/kafka/config/KafkaListenerEndpointRegistry.java

@@ -104,6 +104,7 @@ public Set<String> getListenerContainerIds() {
 	}
 
 	/**
+	 * Return the managed {@link MessageListenerContainer} instance(s).
 	 * @return the managed {@link MessageListenerContainer} instance(s).
 	 */
 	public Collection<MessageListenerContainer> getListenerContainers() {
@@ -262,6 +263,7 @@ public boolean isRunning() {
 	/**
 	 * Start the specified {@link MessageListenerContainer} if it should be started
 	 * on startup.
+	 * @param listenerContainer the listener container to start.
 	 * @see MessageListenerContainer#isAutoStartup()
 	 */
 	private static void startIfNecessary(MessageListenerContainer listenerContainer) {

spring-kafka/src/main/java/org/springframework/kafka/config/MethodKafkaListenerEndpoint.java

@@ -29,6 +29,9 @@
  * A {@link KafkaListenerEndpoint} providing the method to invoke to process
  * an incoming message for this endpoint.
  *
+ * @param <K> the key type.
+ * @param <V> the value type.
+ *
  * @author Stephane Nicoll
  * @author Artem Bilan
  * @author Gary Russell
@@ -77,6 +80,7 @@ public void setMessageHandlerMethodFactory(MessageHandlerMethodFactory messageHa
 	}
 
 	/**
+	 * Return the {@link MessageHandlerMethodFactory}.
 	 * @return the messageHandlerMethodFactory
 	 */
 	protected MessageHandlerMethodFactory getMessageHandlerMethodFactory() {

spring-kafka/src/main/java/org/springframework/kafka/config/MultiMethodKafkaListenerEndpoint.java

@@ -26,8 +26,16 @@
 import org.springframework.messaging.handler.invocation.InvocableHandlerMethod;
 
 /**
+ * The {@link MethodKafkaListenerEndpoint} extension for several POJO methods
+ * based on the {@link org.springframework.kafka.annotation.KafkaHandler}.
+ *
+ * @param <K> the key type.
+ * @param <V> the value type.
+ *
  * @author Gary Russell
  *
+ * @see org.springframework.kafka.annotation.KafkaHandler
+ * @see DelegatingInvocableHandler
  */
 public class MultiMethodKafkaListenerEndpoint<K, V> extends MethodKafkaListenerEndpoint<K, V> {
 

spring-kafka/src/main/java/org/springframework/kafka/config/SimpleKafkaListenerContainerFactory.java

@@ -25,10 +25,13 @@
 /**
  * A {@link KafkaListenerContainerFactory} implementation to build a regular
  * {@link ConcurrentMessageListenerContainer}.
- *
- * <p>This should be the default for most users and a good transition paths
+ * <p>
+ * This should be the default for most users and a good transition paths
  * for those that are used to build such container definition manually.
  *
+ * @param <K> the key type.
+ * @param <V> the value type.
+ *
  * @author Stephane Nicoll
  * @author Gary Russell
  * @author Artem Bilan
@@ -41,6 +44,7 @@ public class SimpleKafkaListenerContainerFactory<K, V>
 	private Long recentOffset;
 
 	/**
+	 * Specify the container concurrency.
 	 * @param concurrency the number of consumers to create.
 	 * @see ConcurrentMessageListenerContainer#setConcurrency(int)
 	 */
@@ -49,6 +53,7 @@ public void setConcurrency(Integer concurrency) {
 	}
 
 	/**
+	 * Specify the offset lag from the end of commit.
 	 * @param recentOffset the recent offset.
 	 * @see ConcurrentMessageListenerContainer#setRecentOffset(long)
 	 */

spring-kafka/src/main/java/org/springframework/kafka/config/SimpleKafkaListenerEndpoint.java

@@ -24,6 +24,9 @@
  * A {@link KafkaListenerEndpoint} simply providing the {@link MessageListener} to
  * invoke to process an incoming message for this endpoint.
  *
+ * @param <K> the key type.
+ * @param <V> the value type.
+ *
  * @author Stephane Nicoll
  * @author Gary Russell
  */
@@ -42,6 +45,8 @@ public void setMessageListener(MessageListener<K, V> messageListener) {
 	}
 
 	/**
+	 * Return the {@link MessageListener} to invoke when a message matching
+	 * the endpoint is received.
 	 * @return the {@link MessageListener} to invoke when a message matching
 	 * the endpoint is received.
 	 */

spring-kafka/src/main/java/org/springframework/kafka/core/ConsumerFactory.java

@@ -19,8 +19,12 @@
 import org.apache.kafka.clients.consumer.Consumer;
 
 /**
- * @author Gary Russell
+ * The strategy to produce a {@link Consumer} instance(s).
+ *
+ * @param <K> the key type.
+ * @param <V> the value type.
  *
+ * @author Gary Russell
  */
 public interface ConsumerFactory<K, V> {