Add type-safe queue properties to AmqpAdmin

Retain (don't deprecate) the current method for JMX users.

* Fix @SInCE

Author: garyrussell

spring-amqp/src/main/java/org/springframework/amqp/core/AmqpAdmin.java

@@ -118,6 +118,14 @@ public interface AmqpAdmin {
 	@Nullable
 	Properties getQueueProperties(String queueName);
 
+	/**
+	 * Returns information about the queue, if it exists.
+	 * @param queueName the name of the queue.
+	 * @return the information or null if the queue doesn't exist.
+	 */
+	@Nullable
+	QueueInformation getQueueInfo(String queueName);
+
 	/**
 	 * Initialize the admin.
 	 * @since 2.1

spring-amqp/src/main/java/org/springframework/amqp/core/QueueInformation.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2019 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.springframework.amqp.core;
+
+/**
+ * Information about a queue, resulting from a passive declaration.
+ *
+ * @author Gary Russell
+ * @since 2.2
+ *
+ */
+public class QueueInformation {
+
+	private final String name;
+
+	private final int messageCount;
+
+	private final int consumerCount;
+
+	public QueueInformation(String name, int messageCount, int consumerCount) {
+		this.name = name;
+		this.messageCount = messageCount;
+		this.consumerCount = consumerCount;
+	}
+
+	public String getName() {
+		return this.name;
+	}
+
+	public int getMessageCount() {
+		return this.messageCount;
+	}
+
+	public int getConsumerCount() {
+		return this.consumerCount;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((this.name == null) ? 0 : this.name.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj) {
+			return true;
+		}
+		if (obj == null) {
+			return false;
+		}
+		if (getClass() != obj.getClass()) {
+			return false;
+		}
+		QueueInformation other = (QueueInformation) obj;
+		if (this.name == null) {
+			if (other.name != null) {
+				return false;
+			}
+		}
+		else if (!this.name.equals(other.name)) {
+			return false;
+		}
+		return true;
+	}
+
+	@Override
+	public String toString() {
+		return "QueueInformation [name=" + this.name + ", messageCount=" + this.messageCount + ", consumerCount="
+				+ this.consumerCount + "]";
+	}
+
+}

spring-rabbit/src/main/java/org/springframework/amqp/rabbit/core/RabbitAdmin.java

@@ -39,6 +39,7 @@
 import org.springframework.amqp.core.Declarables;
 import org.springframework.amqp.core.Exchange;
 import org.springframework.amqp.core.Queue;
+import org.springframework.amqp.core.QueueInformation;
 import org.springframework.amqp.rabbit.connection.CachingConnectionFactory;
 import org.springframework.amqp.rabbit.connection.CachingConnectionFactory.CacheMode;
 import org.springframework.amqp.rabbit.connection.ChannelProxy;
@@ -249,7 +250,7 @@ public boolean deleteExchange(final String exchangeName) {
 			try {
 				channel.exchangeDelete(exchangeName);
 			}
-			catch (IOException e) {
+			catch (@SuppressWarnings("unused") IOException e) {
 				return false;
 			}
 			return true;
@@ -314,7 +315,7 @@ public boolean deleteQueue(final String queueName) {
 			try {
 				channel.queueDelete(queueName);
 			}
-			catch (IOException e) {
+			catch (@SuppressWarnings("unused") IOException e) {
 				return false;
 			}
 			return true;
@@ -397,17 +398,28 @@ public void removeBinding(final Binding binding) {
 	 */
 	@Override
 	@ManagedOperation(description = "Get queue name, message count and consumer count")
-	@Nullable
 	public Properties getQueueProperties(final String queueName) {
+		QueueInformation queueInfo = getQueueInfo(queueName);
+		if (queueInfo != null) {
+			Properties props = new Properties();
+			props.put(QUEUE_NAME, queueInfo.getName());
+			props.put(QUEUE_MESSAGE_COUNT, queueInfo.getMessageCount());
+			props.put(QUEUE_CONSUMER_COUNT, queueInfo.getConsumerCount());
+			return props;
+		}
+		else {
+			return null;
+		}
+	}
+
+	@Override
+	public QueueInformation getQueueInfo(String queueName) {
 		Assert.hasText(queueName, "'queueName' cannot be null or empty");
 		return this.rabbitTemplate.execute(channel -> {
 			try {
 				DeclareOk declareOk = channel.queueDeclarePassive(queueName);
-				Properties props = new Properties();
-				props.put(QUEUE_NAME, declareOk.getQueue());
-				props.put(QUEUE_MESSAGE_COUNT, declareOk.getMessageCount());
-				props.put(QUEUE_CONSUMER_COUNT, declareOk.getConsumerCount());
-				return props;
+				return new QueueInformation(declareOk.getQueue(), declareOk.getMessageCount(),
+						declareOk.getConsumerCount());
 			}
 			catch (IllegalArgumentException e) {
 				if (RabbitAdmin.this.logger.isDebugEnabled()) {
@@ -419,11 +431,11 @@ public Properties getQueueProperties(final String queueName) {
 						((ChannelProxy) channel).getTargetChannel().close();
 					}
 				}
-				catch (TimeoutException e1) {
+				catch (@SuppressWarnings("unused") TimeoutException e1) {
 				}
 				return null;
 			}
-			catch (Exception e) {
+			catch (@SuppressWarnings("unused") Exception e) {
 				if (RabbitAdmin.this.logger.isDebugEnabled()) {
 					RabbitAdmin.this.logger.debug("Queue '" + queueName + "' does not exist");
 				}

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/core/RabbitAdminTests.java

@@ -68,6 +68,7 @@
 import org.springframework.amqp.core.DirectExchange;
 import org.springframework.amqp.core.Exchange;
 import org.springframework.amqp.core.Queue;
+import org.springframework.amqp.core.QueueInformation;
 import org.springframework.amqp.rabbit.connection.CachingConnectionFactory;
 import org.springframework.amqp.rabbit.connection.Connection;
 import org.springframework.amqp.rabbit.connection.ConnectionFactory;
@@ -185,10 +186,9 @@ public void testProperties() throws Exception {
 	}
 
 	private int messageCount(RabbitAdmin rabbitAdmin, String queueName) {
-		Properties props = rabbitAdmin.getQueueProperties(queueName);
-		assertNotNull(props);
-		assertNotNull(props.get(RabbitAdmin.QUEUE_MESSAGE_COUNT));
-		return (Integer) props.get(RabbitAdmin.QUEUE_MESSAGE_COUNT);
+		QueueInformation info = rabbitAdmin.getQueueInfo(queueName);
+		assertNotNull(info);
+		return info.getMessageCount();
 	}
 
 	@Test