在 Java EE 7 应用程序中实现 JAX-WS 服务时出现以下异常。
Warning: Internal Server error: /Test-war/Test.xhtml
java.lang.NullPointerException
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:272)
at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
at java.lang.Thread.run(Thread.java:745)
异常消息似乎非常特定于 GlassFish Server(我使用的是 4.1)。
测试场景:
CDI 托管 bean:
@Named
@ViewScoped
public class TestManagedBean implements Serializable
{
private String test;
private static final long serialVersionUID=1L;
public TestManagedBean() {}
@PostConstruct
private void init() {
TestBean_Service testBean_Service=new TestBean_Service();
TestBean testBean = testBean_Service.getTestBeanPort();
System.out.println("testBean sum = "+testBean.getSum(5, 10));
}
public String getTest() {
return test;
}
}
成员变量test
是没用的。它仅用于测试目的。
在 XHTML 页面中,只需test
像这样访问此字段,
<h:outputText value="#{testManagedBean.test}"/>
以便@PostConstruct
可以调用标记为 的 bean 的方法。
在浏览器的地址栏中输入适当的 URL 时会发生异常。
这testBean.getSum(int, int)
是一个成功调用的远程 EJB 方法,当 bean 更改为单例 EJB 只是为了像这样的测试原因,
import client.web.services.TestBean;
import client.web.services.TestBean_Service;
import javax.annotation.PostConstruct;
import javax.ejb.Singleton;
import javax.ejb.Startup;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
@Startup
@Singleton
@TransactionAttribute(TransactionAttributeType.NOT_SUPPORTED)
public class TestManagedBean
{
public TestManagedBean() {}
@PostConstruct
private void init() {
TestBean_Service testBean_Service=new TestBean_Service();
TestBean testBean = testBean_Service.getTestBeanPort();
System.out.println("testBean sum = "+testBean.getSum(5, 10));
}
}
在这种情况下,getSum(int, int)
在关联的远程 EJB 中实际可用的代理方法被成功调用,并返回通过它提供的两个参数的总和。
java.lang.NullPointerException
当通过 XHTML 页面访问服务时,是什么让 GlassFish 想到?