查找期间的 EJB 3 RemoteInterface 类转换异常

Question

我正在使用 WebSphere Application Server 8.0.0.1。 我有两个企业应用程序在同一个 jvm 中运行（目前）。

我需要远程调用 EJB 方法

1. 应用程序（“服务”） 接口：

   package myfirstpackage.ejb3;
   @Remote
   public interface TriggerManually {
       public boolean runTask(String taskName);
       public boolean resetTasks();
   }
   

   实施：

   package anotherpackage.ejb.remoteclient;
   @Stateless
   public class TriggerManuallyBean implements TriggerManually {
       @Override
       public boolean runTask(String taskName) {
           //Syso...
           return false;
       }
   
       @Override
       public boolean resetTasks() {
           //Syso...
           return false;
       }
   
   }
   

2. 应用程序（“客户端”）使用服务（接口是共享的）

   public class TriggerManuallyClient {
     public void test() {
       Properties props = new Properties();
   
       props.put(Context.INITIAL_CONTEXT_FACTORY,
               "com.ibm.websphere.naming.WsnInitialContextFactory");
       props.put(javax.naming.Context.PROVIDER_URL, "iiop://localhost:2811");
   
       TriggerManually triggerManually;
       try {
           InitialContext ctx = new InitialContext(props);
           triggerManually = (TriggerManually) ctx
                   .lookup("myjdniname");
           triggerManually.resetTasks();
   
       } catch (NamingException e) {
           e.printStackTrace();
       }
     }
   }
   

但是我在查找过程中遇到了 Class Cast 异常：

Exception created : [java.lang.ClassCastException: myfirstpackage.ejb3._TriggerManually_Stub incompatible with anotherpackage.ejb.remoteclient.TriggerManually
    at anotherpackage.ejb.remoteclient.TriggerManuallyClient.test(TriggerManuallyClient.java:20)
    at com.ibm._jsp._status._jspService(_status.java:112)
    at com.ibm.ws.jsp.runtime.HttpJspBase.service(HttpJspBase.java:99)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:668)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1147)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:722)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:449)
    at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:178)
    at com.ibm.wsspi.webcontainer.servlet.GenericServletWrapper.handleRequest(GenericServletWrapper.java:122)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionServletWrapper.handleRequest(AbstractJSPExtensionServletWrapper.java:205)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.invokeTarget(WebAppFilterChain.java:125)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:77)
    at com.ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter(WebAppFilterManager.java:919)
    at com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1016)
    at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:87)
    at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:886)
    at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1655)
    at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:195)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:452)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewRequest(HttpInboundLink.java:511)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.processRequest(HttpInboundLink.java:305)
    at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:83)
    at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:165)
    at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
    at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
    at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
    at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:204)
    at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:775)
    at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:905)
    at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1650)

我认为在 EJB 3 中我不必创建存根。我该如何解决我的问题？

Answer 1

问题不在于通过查找返回的存根（是的，那些仍然存在于 EJB3 中）。

仔细看ClassCastException：

myfirstpackage.ejb3._TriggerManually_Stub incompatible with anotherpackage.ejb.remoteclient.TriggerManually

您可能在包anotherpackage.ejb.remoteclient 中也有一个TriggerManually 类。

这可能会解决它：

myfirstpackage.ejb3.TriggerManually triggerManually;
try {
    InitialContext ctx = new InitialContext(props);
    triggerManually = (myfirstpackage.ejb3.TriggerManually) ctx.lookup("myjdniname");
    triggerManually.resetTasks();

} catch (NamingException e) {
    e.printStackTrace();
}

Answer 2

在 Maven 中清理构建您的项目。