本节演示发布/订阅(publish-subscribe)模式的消息发送的 Spring + ActiveMQ 代码。
1、生产者代码
- spring 关键代码:springContext-activemq.xml
xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<!-- 创建一个ConnectionFactory,为了提升性能用了连接池 -->
<bean id="connectionFactory" class="org.apache.activemq.pool.PooledConnectionFactory"
destroy-method="stop">
<property name="connectionFactory">
<bean class="org.apache.activemq.ActiveMQConnectionFactory">
<property name="brokerURL">
<value>tcp://localhost:61616</value>
</property>
</bean>
</property>
<property name="maxConnections" value="50" />
</bean>
<!-- 创建消息目的地,constructor-arg是目的地的名称,此处为spring-topic -->
<bean id="destinationTopic" class="org.apache.activemq.command.ActiveMQTopic">
<constructor-arg index="0" value="spring-topic" />
</bean>
<!-- 构建JmsTemplate -->
<bean id="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">
<property name="connectionFactory" ref="connectionFactory" />
<property name="defaultDestination" ref="destinationTopic" />
<property name="messageConverter">
<bean
class="org.springframework.jms.support.converter.SimpleMessageConverter" />
</property>
</bean>
</beans>
生产者关键代码:SpringTopicSender
swift
package producer;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.Session;
import javax.jms.TextMessage;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.core.MessageCreator;
/**
* 发布/订阅(publish-subscribe)消息发送,spring整合
*
* @author JPM
*/
public class SpringTopicSender {
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
"classpath:spring/springContext-activemq.xml");
JmsTemplate jmsTemplate = (JmsTemplate) context.getBean("jmsTemplate");
jmsTemplate.send(new MessageCreator() {
public Message createMessage(Session session) throws JMSException {
TextMessage message = session.createTextMessage();
message.setText("hello,spring-topic!");
return message;
}
});
context.close();
}
}
运行 SpringTopicSender 类,查看 ActiveMQ 管理界面
说明已经发布了一个主题消息。
2、消费者代码(receive 方法获取消息)
- spring 关键代码:springContext-activemq.xml
xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="connectionFactory" class="org.apache.activemq.pool.PooledConnectionFactory"
destroy-method="stop">
<property name="connectionFactory">
<bean class="org.apache.activemq.ActiveMQConnectionFactory">
<property name="brokerURL">
<value>tcp://localhost:61616</value>
</property>
</bean>
</property>
<property name="maxConnections" value="50" />
</bean>
<bean id="destinationTopic" class="org.apache.activemq.command.ActiveMQTopic">
<constructor-arg index="0" value="spring-topic" />
</bean>
<bean id="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">
<property name="connectionFactory" ref="connectionFactory" />
<property name="defaultDestination" ref="destinationTopic" />
<property name="messageConverter">
<bean
class="org.springframework.jms.support.converter.SimpleMessageConverter" />
</property>
</bean>
</beans>
消费者关键代码:SpringTopicReceiver1 和 SpringTopicReceiver2
typescript
package consumer;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jms.core.JmsTemplate;
/**
* 发布/订阅(publish-subscribe)消息接收1,spring整合
*
* @author JPM
*/
public class SpringTopicReceiver1 {
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
"classpath:spring/springContext-activemq.xml");
JmsTemplate jmsTemplate = (JmsTemplate) context.getBean("jmsTemplate");
String message = (String) jmsTemplate.receiveAndConvert();
System.out.println("SpringTopicReceiver1--->" + message);
context.close();
}
}
typescript
package consumer;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jms.core.JmsTemplate;
/**
* 发布/订阅(publish-subscribe)消息接收2,spring整合
*
* @author JPM
*/
public class SpringTopicReceiver2 {
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
"classpath:spring/springContext-activemq.xml");
JmsTemplate jmsTemplate = (JmsTemplate) context.getBean("jmsTemplate");
String message = (String) jmsTemplate.receiveAndConvert();
System.out.println("SpringTopicReceiver2--->" + message);
context.close();
}
}
运行 SpringTopicReceiver1 和 SpringTopicReceiver2 类,查看控制台和 ActiveMQ 管理界面
说明2个消费者已经启动,但是看控制台输出都是空的,说明没有消费到消息,原因是对于 topic 消息来说,消费者必须先启动,订阅了主题,然后才能收到主题发来的消息。我们刚才是先发送的主题消息,后启动的消费者,因此2个消费者都没有输出。
下面我们再通过刚才的生产者 SpringTopicSender 类发送一个主题消息,观察消费者的控制台和 ActiveMQ 管理界面的变化
说明,2个消费者都获取到了主题消息。
3、消费者代码(使用消息监听器获取消息)
spring 关键代码 springContext-activemq1.xml
xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="connectionFactory" class="org.apache.activemq.pool.PooledConnectionFactory"
destroy-method="stop">
<property name="connectionFactory">
<bean class="org.apache.activemq.ActiveMQConnectionFactory">
<property name="brokerURL">
<value>tcp://localhost:61616</value>
</property>
</bean>
</property>
<property name="maxConnections" value="50" />
</bean>
<bean id="destinationTopic" class="org.apache.activemq.command.ActiveMQTopic">
<constructor-arg index="0" value="spring-topic" />
</bean>
<bean id="jmsContainer1"
class="org.springframework.jms.listener.DefaultMessageListenerContainer">
<property name="connectionFactory" ref="connectionFactory" />
<property name="destination" ref="destinationTopic" />
<property name="messageListener" ref="messageListener1" />
</bean>
<bean id="messageListener1" class="consumer.SpringTopicListener1" />
</beans>
springContext-activemq2.xml
xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="connectionFactory" class="org.apache.activemq.pool.PooledConnectionFactory"
destroy-method="stop">
<property name="connectionFactory">
<bean class="org.apache.activemq.ActiveMQConnectionFactory">
<property name="brokerURL">
<value>tcp://localhost:61616</value>
</property>
</bean>
</property>
<property name="maxConnections" value="50" />
</bean>
<bean id="destinationTopic" class="org.apache.activemq.command.ActiveMQTopic">
<constructor-arg index="0" value="spring-topic" />
</bean>
<bean id="jmsContainer2"
class="org.springframework.jms.listener.DefaultMessageListenerContainer">
<property name="connectionFactory" ref="connectionFactory" />
<property name="destination" ref="destinationTopic" />
<property name="messageListener" ref="messageListener2" />
</bean>
<bean id="messageListener2" class="consumer.SpringTopicListener2" />
</beans>
消费者关键代码 SpringTopicListener1
java
package consumer;
import java.io.IOException;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.TextMessage;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* 发布/订阅(publish-subscribe)消息接收1,spring整合,使用Listener
*
* @author JPM
*/
public class SpringTopicListener1 implements MessageListener {
public void onMessage(Message message) {
String msg = null;
try {
msg = ((TextMessage) message).getText();
} catch (JMSException e) {
e.printStackTrace();
}
System.out.println("SpringTopicListener1--->" + msg);
}
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
"classpath:spring/springContext-activemq1 .xml");
try {
System.in.read();
} catch (IOException e) {
e.printStackTrace();
}
context.close();
}
}
SpringTopicListener2
java
package consumer;
import java.io.IOException;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.TextMessage;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* 发布/订阅(publish-subscribe)消息接收2,spring整合,使用Listener
*
* @author JPM
*/
public class SpringTopicListener2 implements MessageListener {
public void onMessage(Message message) {
String msg = null;
try {
msg = ((TextMessage) message).getText();
} catch (JMSException e) {
e.printStackTrace();
}
System.out.println("SpringTopicListener2--->" + msg);
}
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
"classpath:spring/springContext-activemq2.xml");
try {
System.in.read();
} catch (IOException e) {
e.printStackTrace();
}
context.close();
}
}
运行 SpringTopicListener1 和 SpringTopicListener2 类,查看 ActiveMQ 管理界面
成功启动一个消费者
成功启动第二个消费者。
首先运行刚才的生产者 SpringTopicSender 类发送一条主题消息,查看 ActiveMQ 管理界面
说明消费了主题消息。
查看 SpringTopicListener1 和 SpringTopicListener2 的控制台
从控制台来看,两个订阅者都获取到了生产者发布的消息。