我尝试运行简单的spring jmstemplate示例。这里是发送方的源代码，
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.Session;
import javax.jms.TextMessage;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.core.MessageCreator;
public class MessageSender {
@Autowired
private JmsTemplate jmsTemplate;
public void setJmsTemplate(JmsTemplate jmsTemplate)
{
this.jmsTemplate = jmsTemplate;
}
public void sendMessage()
{
jmsTemplate.send(new MessageCreator() {
public Message createMessage(Session session)
{
TextMessage message = null;
try
{
message = session.createTextMessage();
message.setStringProperty("text", "Hello World");
}
catch (JMSException e)
{
e.printStackTrace();
}
return message;
}
});
}
}
这是用于将spring与jmstemplate集成的配置文件。
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
<!-- Spring AOP -->
<context:component-scan base-package="com.test"/>
<aop:aspectj-autoproxy />
<bean id="messageListener" class="com.test.QueuereceiverDB" />
<bean id="jndiTemplate" class="org.springframework.jndi.JndiTemplate">
<property name="environment">
<props>
<prop key="java.naming.provider.url">jnp://localhost:1099</prop>
<prop key="java.naming.factory.url.pkgs">org.jnp.interfaces:org.jboss.naming</prop>
<prop key="java.naming.factory.initial">org.jnp.interfaces.NamingContextFactory</prop>
</props>
</property>
</bean>
<bean id="queueConnectionFactory" class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiTemplate">
<ref bean="jndiTemplate" />
</property>
<property name="jndiName">
<value>ConnectionFactory</value>
</property>
</bean>
<bean id="jmsDestinationResolver" class="org.springframework.jms.support.destination.JndiDestinationResolver">
<property name="jndiTemplate">
<ref bean="jndiTemplate" />
</property>
<property name="cache">
<value>true</value>
</property>
</bean>
<bean id="QueueTemplate" class="org.springframework.jms.core.JmsTemplate">
<property name="connectionFactory">
<ref bean="queueConnectionFactory" />
</property>
<property name="destinationResolver">
<ref bean="jmsDestinationResolver" />
</property>
</bean>
<bean id="jmsSender" class="com.test.MessageSender">
<property name="jmsTemplate"> <ref bean="QueueTemplate" />
</property>
</bean>
<bean id="Queue" class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiTemplate"> <ref bean="jndiTemplate" />
</property>
<property name="jndiName">
<value>queue/MyQueue</value>
</property>
</bean>
<!-- JmsTemplate Definition -->
<bean id="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">
<property name="connectionFactory" ref="queueConnectionFactory" />
<property name="defaultDestination" ref="Queue" />
</bean>
<bean id="jmscontainer" class="org.springframework.jms.listener.DefaultMessageListenerContainer">
<property name="concurrentConsumers" value="5" />
<property name="connectionFactory" ref="queueConnectionFactory" />
<property name="destination" ref="Queue" />
<property name="messageListener" ref="messageListener" />
</bean>
</beans>
如果我运行下面的示例是相应的堆栈跟踪
SEVERE [com.sun.jersey.spi.container.ContainerResponse] The RuntimeException could not be mapped to a response, re-throwing to the HTTP container: java.lang.NullPointerException
at com.test.MessageSender.sendMessage(MessageSender.java:30) [:]
at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149) [:]
at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:689) [:3.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) [:3.1.0.RELEASE]
at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:55) [:3.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:161) [:3.1.0.RELEASE]
at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:50) [:3.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:161) [:3.1.0.RELEASE]
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:50) [:3.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:161) [:3.1.0.RELEASE]
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:80) [:3.1.0.RELEASE]
在调试代码后，我发现了问题所在，jmsTemplate.send（new MessageCreator（）{执行此行时将显示Null指针。
我认为我们需要从xml文件初始化jmstemplate。但是我不知道如何实现这一点？
请帮我一个人。
我在以下文件中配置了队列，该文件将放置在jboss / server / default / server文件夹中
mdb-hornetq-xml
<?xml version="1.0" encoding="UTF-8"?>
<configuration xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="urn:hornetq"
xsi:schemaLocation="urn:hornetq /schema/hornetq-jms.xsd" >
<queue name="MyQueue2" >
<entry name="/queue/MyQueue" />
</queue>
</configuration>
最佳答案
我感到奇怪的是，您声明了两个JmsTemplate bean。我有一个更简单的配置可以工作。涉及两个JNDI名称，一个是目标（队列）名称，另一个是连接工厂名称。
假设您的队列是MyQueue，连接工厂是MyCF。要发送消息，您只需要声明两个spring bean：
<bean id="jmsConnectionFactory" class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="MyCF"/>
<property name="lookupOnStartup" value="false"/>
<property name="cache" value="true"/>
<property name="proxyInterface" value="javax.jms.ConnectionFactory"/>
</bean>
<bean name="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">
<property name="connectionFactory">
<ref bean="jmsConnectionFactory"/>
</property>
<property name="defaultDestinationName" value="MyQueue" />
</bean>
然后，sender类中的源代码将包含：
@Autowired
private JmsTemplate jmsTemplate;
private void sendTextMessage(final String message)
MessageCreator messageCreator = new MessageCreator() {
@Override
public Message createMessage(Session session) throws JMSException {
return session.createTextMessage(message);
}
};
jmsTemplate.send(messageCreator);
}
缺少的是连接工厂和队列的HornetQ配置。该配置定义了JNDI名称。在我的情况下，HornetQ与JBoss Application Server一起嵌入式运行。因此，我在JBoss AS配置中（例如在standalone.xml文件中）配置了连接工厂和队列。以下是片段：
<pooled-connection-factory name="hornetq-local">
<transaction mode="local"/>
<connectors>
<connector-ref connector-name="in-vm"/>
</connectors>
<entries>
<entry name="java:/MyCF"/>
</entries>
</pooled-connection-factory>
<jms-destinations>
<jms-queue name="MyQueue">
<entry name="java:jboss/queues/a/b/SomeQueue"/>
<durable>true</durable>
</jms-queue>
</jms-destinations>
我相信您在独立模式下使用HornetQ。将这些设置映射到工厂并在那里进行队列配置应该很容易。
关于java - JmsTemplate中的空指针异常？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/21200425/