ActiveMQ和嵌入式代理

Question

编辑:改述问题:

我想使用ActiveMQ作为我的服务器和客户端应用程序之间的信使服务.

我试图在服务器中设置一个嵌入式代理(即不是一个单独的进程)来处理生成的消息供我的客户端使用.此队列是持久的.

经纪人初始化如下:

BrokerService broker = new BrokerService();
KahaPersistenceAdapter adaptor = new KahaPersistenceAdapter();
adaptor.setDirectory(new File("activemq"));
broker.setPersistenceAdapter(adaptor);
broker.setUseJmx(true);
broker.addConnector("tcp://localhost:61616");
broker.start();

经过修修补补后,我最终得到的服务器部分是:

public static class HelloWorldProducer implements Runnable {
    public void run() {
        try {
            ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory("tcp://localhost"); // apparently the vm part is all i need
            Connection connection = connectionFactory.createConnection(); 
            connection.start();
            Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            Destination destination = session.createQueue("TEST.FOO");
            MessageProducer producer = session.createProducer(destination);
            producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
            String text = "Hello world! From: " + Thread.currentThread().getName() + " : " + this.hashCode();
            TextMessage message = session.createTextMessage(text);
            System.out.println("Sent message: "+ message.hashCode() + " : " + Thread.currentThread().getName());
            producer.send(message);
            session.close();
            connection.close();
        }
        catch (Exception e) {
            System.out.println("Caught: " + e);
            e.printStackTrace();
        }
    }
}

客户端非常相似,看起来像这样:

public static class HelloWorldConsumer implements Runnable, ExceptionListener {
    public void run() {
        try {
          ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory("tcp://localhost");
            Connection connection = connectionFactory.createConnection(); // exception happens here...
            connection.start();
            connection.setExceptionListener(this);
            Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            Destination destination = session.createQueue("TEST.FOO");
            MessageConsumer consumer = session.createConsumer(destination);
            Message message = consumer.receive(1000);
            if (message instanceof TextMessage) {
                TextMessage textMessage = (TextMessage) message;
                String text = textMessage.getText();
                System.out.println("*****Received: " + text);
            } else {
                System.out.println("*****Received obj: " + message);
            }
            consumer.close();
            session.close();
            connection.close();
        } catch (Exception e) {
            System.out.println("Caught: " + e);
            e.printStackTrace();
        }
    }

main方法只是在一个线程中启动它们中的每一个以开始生成/接收消息.

...但是我在每个线程的开头遇到以下问题:

2013-01-24 07:54:31,271 INFO  [org.apache.activemq.broker.BrokerService] Using Persistence Adapter: AMQPersistenceAdapter(activemq-data/localhost)
2013-01-24 07:54:31,281 INFO  [org.apache.activemq.store.amq.AMQPersistenceAdapter] AMQStore starting using directory: activemq-data/localhost
2013-01-24 07:54:31,302 INFO  [org.apache.activemq.kaha.impl.KahaStore] Kaha Store using data directory activemq-data/localhost/kr-store/state
2013-01-24 07:54:31,339 INFO  [org.apache.activemq.store.amq.AMQPersistenceAdapter] Active data files: []
2013-01-24 07:54:31,445 DEBUG [org.apache.activemq.broker.jmx.ManagementContext] Probably not using JRE 1.4: mx4j.tools.naming.NamingService
2013-01-24 07:54:31,450 DEBUG [org.apache.activemq.broker.jmx.ManagementContext] Failed to create local registry
    java.rmi.server.ExportException: internal error: ObjID already in use
    at sun.rmi.transport.ObjectTable.putTarget(ObjectTable.java:186)
    at sun.rmi.transport.Transport.exportObject(Transport.java:92)
    at sun.rmi.transport.tcp.TCPTransport.exportObject(TCPTransport.java:247)
    at sun.rmi.transport.tcp.TCPEndpoint.exportObject(TCPEndpoint.java:411)
    at sun.rmi.transport.LiveRef.exportObject(LiveRef.java:147)
        <snip....>

看起来消息是成功生成和消费的(我之前发布的其他问题已经解决了),但上面的例外令我担心.

编辑:在经纪人关闭期间,我现在也受到以下问题的欢迎:

2013-01-25 08:40:17,486 DEBUG [org.apache.activemq.transport.failover.FailoverTransport] Transport failed with the following exception:
    java.io.EOFException
    at java.io.DataInputStream.readInt(DataInputStream.java:392)
    at org.apache.activemq.openwire.OpenWireFormat.unmarshal(OpenWireFormat.java:269)
    at org.apache.activemq.transport.tcp.TcpTransport.readCommand(TcpTransport.java:210)
    at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:202)
    at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:185)
    at java.lang.Thread.run(Thread.java:722)

Answer 1

您可以通过多种方式将代理嵌入到代码中,其中大部分都记录在此处.您可能想尝试升级您的版本,因为您使用的内容似乎已经很老了,因为它默认为现在已弃用的AMQ商店而不是较新的KahaDB商店.您可能遇到问题,因为客户端线程之间的竞争使用了可能竞争在VM代理中创建的不同连接工厂.如果在生产者上设置create = false选项并确保在此之后启动消费者线程可以解决问题,或者您可以提前创建VM代理并向两个线程添加create = false,这可能会起作用.

BrokerService broker = new BrokerService();
// configure the broker
broker.setBrokerName("localhost");
broker.setUseJmx(false);
broker.start();

然后在客户端代码中通过此连接工厂配置进行附加.

ActiveMQConnectionFactory cf = new ActiveMQConnectionFactory("vm://localhost?create=false");