我是JMS的新手,想要创建一个发送消息的基本MessageProducer和异步接收该消息的MessageConsumer。当我运行此代码时,出现错误消息:
MessageProducer.java
package activemq.test;
import java.util.Date;
import org.apache.activemq.ActiveMQConnectionFactory;
import javax.jms.*;
public class MessageProducer{
javax.jms.MessageProducer producer = null;
Connection connection = null;
Session session = null;
public MessageProducer(){
try {
// Create a ConnectionFactory
ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory("tcp://localhost:61616");
// Create a Connection
connection = connectionFactory.createConnection();
connection.start();
// Create a Session
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the destination (Topic or Queue)
Destination destination = session.createQueue("TEST.FOO");
// Create a MessageProducer from the Session to the Topic or Queue
producer = session.createProducer(destination);
producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
// Create a messages
String text = "Hello world! From: MessageProducer";
TextMessage message = session.createTextMessage(text);
// Tell the producer to send the message
System.out.println("Producer is going to send a message");
producer.send(message);
} catch (Exception e) {
System.out.println("Caught: " + e);
e.printStackTrace();
}
}
public void sendMessage(){
try
{
// Create a messages
String text = "Hello world! From: " + new Date();
TextMessage message = session.createTextMessage(text);
// Tell the producer to send the message
System.out.println("Sent message: "+ message.hashCode());
producer.send(message);
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void close(){
// Clean up
try {
session.close();
connection.close();
} catch (JMSException e) {
e.printStackTrace();
}
}
}
MessageConsumer.java
package activemq.test;
import org.apache.activemq.ActiveMQConnectionFactory;
import javax.jms.*;
public class MessageConsumer implements ExceptionListener{
Connection connection = null;
javax.jms.MessageConsumer consumer = null;
Session session = null;
public MessageConsumer(){
try {
// Create a ConnectionFactory
ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory("tcp://localhost:61616");
// Create a Connection
connection = connectionFactory.createConnection();
connection.start();
connection.setExceptionListener(this);
// Create a Session
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the destination (Topic or Queue)
Destination destination = session.createQueue("TEST.FOO");
// Create a MessageConsumer from the Session to the Topic or Queue
consumer = session.createConsumer(destination);
MessageListener listener = new MessageListener() {
public void onMessage(Message message) {
try {
if (message instanceof TextMessage) {
TextMessage textMessage = (TextMessage) message;
System.out.println("Received message"
+ textMessage.getText() + "'");
}
} catch (JMSException e) {
System.out.println("Caught:" + e);
e.printStackTrace();
}
}
};
consumer.setMessageListener(listener);
} catch (Exception e) {
System.out.println("Caught: " + e);
e.printStackTrace();
}
}
@Override
public void onException(JMSException exception) {
System.out.println("JMS Exception occured. Shutting down client.");
}
public void close(){
// Clean up
try {
consumer.close();
session.close();
connection.close();
} catch (JMSException e) {
e.printStackTrace();
}
}
}
AppMain.java
public class AppMain {
public static void main(final String arg[]) throws Exception
{
MessageProducer msProducer = new MessageProducer();
msProducer.sendMessage();
msProducer.close();
MessageConsumer msConsumer = new MessageConsumer();
msConsumer.close();
}
}
创建MessageConsumer时,出现错误消息:
Caught: javax.jms.JMSException: AMQ119017: Queue jms.queue.TEST.FOO does not exist
javax.jms.JMSException: AMQ119017: Queue jms.queue.TEST.FOO does not exist
at org.apache.activemq.util.JMSExceptionSupport.create(JMSExceptionSupport.java:54)
at org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1405)
at org.apache.activemq.ActiveMQSession.syncSendPacket(ActiveMQSession.java:1925)
at org.apache.activemq.ActiveMQMessageConsumer.<init>(ActiveMQMessageConsumer.java:275)
at org.apache.activemq.ActiveMQSession.createConsumer(ActiveMQSession.java:1157)
at org.apache.activemq.ActiveMQSession.createConsumer(ActiveMQSession.java:1101)
at org.apache.activemq.ActiveMQSession.createConsumer(ActiveMQSession.java:1014)
at org.apache.activemq.ActiveMQSession.createConsumer(ActiveMQSession.java:987)
at activemq.test.MessageConsumer.<init>(MessageConsumer.java:36)
at activemq.test.AppMain.main(AppMain.java:17)
Caused by: ActiveMQNonExistentQueueException[errorType=QUEUE_DOES_NOT_EXIST message=AMQ119017: Queue jms.queue.TEST.FOO does not exist]
at org.apache.activemq.core.server.impl.ServerSessionImpl.createConsumer(ServerSessionImpl.java:448)
at org.apache.activemq.core.protocol.openwire.amq.AMQServerSession.createConsumer(AMQServerSession.java:326)
at org.apache.activemq.core.protocol.openwire.amq.AMQConsumer.init(AMQConsumer.java:138)
at org.apache.activemq.core.protocol.openwire.amq.AMQSession.createConsumer(AMQSession.java:144)
at org.apache.activemq.core.protocol.openwire.OpenWireProtocolManager.addConsumer(OpenWireProtocolManager.java:544)
at org.apache.activemq.core.protocol.openwire.OpenWireConnection.processAddConsumer(OpenWireConnection.java:1118)
at org.apache.activemq.command.ConsumerInfo.visit(ConsumerInfo.java:347)
at org.apache.activemq.core.protocol.openwire.OpenWireConnection.bufferReceived(OpenWireConnection.java:272)
at org.apache.activemq.core.remoting.server.impl.RemotingServiceImpl$DelegatingBufferHandler.bufferReceived(RemotingServiceImpl.java:678)
at org.apache.activemq.core.remoting.impl.netty.ActiveMQChannelHandler.channelRead(ActiveMQChannelHandler.java:77)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:332)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:318)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:787)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:125)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:507)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:464)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:378)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:350)
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
at java.lang.Thread.run(Thread.java:745)
为什么在创建MessageConsumer时收到此错误,但在创建MessageProducer时却没有收到此错误。
我使用ActiveMQServer作为代理:
Server.java
package activemq.test;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import org.apache.activemq.api.core.TransportConfiguration;
import org.apache.activemq.core.config.Configuration;
import org.apache.activemq.core.config.impl.ConfigurationImpl;
import org.apache.activemq.core.remoting.impl.netty.NettyAcceptorFactory;
import org.apache.activemq.core.server.ActiveMQServer;
import org.apache.activemq.core.server.ActiveMQServers;
public class Server {
public static void main(final String arg[]) throws Exception
{
try
{
// Step 1. Create the Configuration, and set the properties accordingly
Configuration configuration = new ConfigurationImpl();
//we only need this for the server lock file
configuration.setJournalDirectory("target/data/journal");
configuration.setPersistenceEnabled(false); // http://activemq.apache.org/what-is-the-difference-between-persistent-and-non-persistent-delivery.html
configuration.setSecurityEnabled(false); // http://activemq.apache.org/security.html
/**
* this map with configuration values is not necessary (it configures the default values).
* If you want to modify it to run the example in two different hosts, remember to also
* modify the client's Connector at {@link EmbeddedRemoteExample}.
*/
Map<String, Object> map = new HashMap<String, Object>();
map.put("host", "localhost");
map.put("port", 61616);
// https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/5/html/HornetQ_User_Guide/ch14s04.html
TransportConfiguration transpConf = new TransportConfiguration(NettyAcceptorFactory.class.getName(),map);
HashSet<TransportConfiguration> setTransp = new HashSet<TransportConfiguration>();
setTransp.add(transpConf);
configuration.setAcceptorConfigurations(setTransp); // https://github.com/apache/activemq-6/blob/master/activemq-server/src/main/java/org/apache/activemq/spi/core/remoting/Acceptor.java
// Step 2. Create and start the server
ActiveMQServer server = ActiveMQServers.newActiveMQServer(configuration);
server.start();
}
catch (Exception e)
{
e.printStackTrace();
throw e;
}
}
}
最佳答案
我认为,在生产者中,您是在设置目标之前启动连接。
之后再尝试...。
// Create a ConnectionFactory
ActiveMQConnectionFactory connectionFactory = new
ActiveMQConnectionFactory("tcp://localhost:61616");
// Create a Connection
connection = connectionFactory.createConnection();
// Create a Session
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the destination (Topic or Queue)
Destination destination = session.createQueue("TEST.FOO");
// Create a MessageProducer from the Session to the Topic or Queue
producer = session.createProducer(destination);
producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
connection.start();
// Create a messages
String text = "Hello world! From: MessageProducer";
TextMessage message = session.createTextMessage(text);
// Tell the producer to send the message
System.out.println("Producer is going to send a message");
producer.send(message);
另一方面,对于消费者,我建议实现MessageConsumer(而不是Exception)。
一旦实现,就可以在构造函数中启动使用者
ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory(url);
connection = factory.createConnection();
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the destination (Topic or Queue)
Destination destination = session.createQueue("TEST.FOO");
// Create a MessageConsumer from the Session to the Topic or Queue
consumer = session.createConsumer(destination).setMessageListener(this);
connection.start();
....
然后实现onMessage方法
public void onMessage(Message message) {
try {
if (message instanceof TextMessage) {
TextMessage textMessage = (TextMessage) message;
System.out.println("Received message"
+ textMessage.getText() + "'");
}
} catch (JMSException e) {
System.out.println("Caught:" + e);
e.printStackTrace();
}
}
关于java - JMSException:队列不存在,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/29942381/