Question

尝试在Netbeans 6.5 / windows xp中撤消远程方法时在RMI中遇到UnmarshalException ClassNotFoundException。 rmi客户端和服务器程序都在同一台机器上运行。

RMI客户端计划：

源代码位置

F：\ NewRMIClient \ SRC \ newrmiclient \ RMIClient.java
F：\ NewRMIClient \ SRC \ newrmiclient \ RemoteInterface.java

班级档案位置

F：\ NewRMIClient \建立\类\ newrmiclient \ RemoteInterface.class
F：\ NewRMIClient \建立\类\ newrmiclient \ RMIClient.class

建立JAR文件位置

F：\ NewRMIClient \ DIST \ NewRMIClient.jar

RemoteInterface.java

package newrmiclient;

import java.rmi.Remote; import java.rmi.RemoteException;

public interface RemoteInterface扩展了Remote { void sendMessageFilePath（String messagePath）抛出RemoteException; }

RMIClient.java

package newrmiclient;

import java.rmi.*;
import java.rmi.registry.*;

public class RMIClient
{
    static public void main(String args[])
    {
       RemoteInterface rmiServer;
       Registry registry;
       String serverAddress="192.169.4.11";
       String serverPort="3232";
       String text="hello";
       System.out.println("sending "+text+" to "+serverAddress+":"+serverPort);

        System.setProperty("java.security.policy","file:/F:/PolicyFiles/rules.policy");

        if(System.getSecurityManager() == null)
        {
           System.setSecurityManager(new RMISecurityManager());
        }

       try{
           // get the “registry”
           registry=LocateRegistry.getRegistry(serverAddress,(new Integer(serverPort)).intValue());
           // look up the remote object
           rmiServer=(RemoteInterface)(registry.lookup("MessagePath"));
           // call the remote method
           rmiServer.sendMessageFilePath(text);
       }
       catch(RemoteException e){
           e.printStackTrace();
       }
       catch(NotBoundException e){
           e.printStackTrace();
       }
    }
}

RMI服务器程序：

源代码位置

F：\ RMIProj \ SRC \ rmiproj \ RemoteInterface.java
F：\ RMIProj \ SRC \ rmiproj \ RmiServer.java

班级档案位置

F：\ RMIProj \建立\类\ rmiproj \ RemoteInterface.class
F：\ RMIProj \建立\类\ rmiproj \ RmiServer.class
F：\ RMIProj \建立\类\ rmiproj \ RmiServer_Skel.class
F：\ RMIProj \建立\类\ rmiproj \ RmiServer_Stub.class

建立JAR位置

F：\ RMIProj \ DIST \ RMIProj.jar

RemoteInterface.java

 package rmiproj;

import java.rmi.Remote;
import java.rmi.RemoteException;

public interface RemoteInterface extends Remote
{
    void sendMessageFilePath(String messagePath) throws RemoteException;
}

RmiServer.java

package rmiproj;

import java.rmi.RMISecurityManager;
import java.rmi.server.UnicastRemoteObject;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;

public class RmiServer extends UnicastRemoteObject implements RemoteInterface
{
    int      thisPort = 3232;

    Registry registry;    // rmi registry for lookup the remote objects.

    public RmiServer() throws RemoteException
    {
        try
        {
            System.setProperty("java.rmi.server.codebase","file:/F:/RMIProj/");
            System.setProperty("java.rmi.server.hostname","RMIServer");
            System.setProperty("java.security.policy","file:/F:/PolicyFiles/rules.policy");

            if(System.getSecurityManager() == null)
            {
                System.setSecurityManager(new RMISecurityManager());
            }

            // create the registry and bind the name and object.
            registry = LocateRegistry.createRegistry( thisPort );
            registry.rebind("MessagePath", this);
        }
        catch(RemoteException re)
        {
            re.printStackTrace();
        }
    }

    // This method is called from the remote client by the RMI.
    // This is the implementation of the “RemoteInterface”.
    public void sendMessageFilePath(String messageFilePath) throws RemoteException
    {
        System.out.println(messageFilePath);
    }

    public static void main(String args[]) throws RemoteException
    {
         RmiServer s=new RmiServer();
     }
}

政策档案的位置： F：\ PolicyFiles \ rules.policy

rules.policy 授予{ permission java.security.AllPermission; };

尝试从客户端调用远程方法时，在控制台上抛出以下异常：

sending hello to 192.169.4.11:3232
java.rmi.UnmarshalException: error unmarshalling return; nested exception is: 
        java.lang.ClassNotFoundException: rmiproj.RemoteInterface
        at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
        at newrmiclient.RMIClient.main(RMIClient.java:28)
Caused by: java.lang.ClassNotFoundException: rmiproj.RemoteInterface
        at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:247)
        at sun.rmi.server.LoaderHandler.loadProxyInterfaces(LoaderHandler.java:711)
        at sun.rmi.server.LoaderHandler.loadProxyClass(LoaderHandler.java:655)
        at sun.rmi.server.LoaderHandler.loadProxyClass(LoaderHandler.java:592)
        at java.rmi.server.RMIClassLoader$2.loadProxyClass(RMIClassLoader.java:628)
        at java.rmi.server.RMIClassLoader.loadProxyClass(RMIClassLoader.java:294)
        at sun.rmi.server.MarshalInputStream.resolveProxyClass(MarshalInputStream.java:238)
        at java.io.ObjectInputStream.readProxyDesc(ObjectInputStream.java:1531)
        at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1493)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1732)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
        at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351)

请帮我解决此问题。

Answer 1

您需要在客户端JVM中提供rmiproj.RemoteInterface类。尝试在rmiproj.RemoteInterface（或客户端类路径中包含的其他JAR）中包含NewRMIClient.jar。

另请注意，您正在调用的远程Object实现rmiproj.RemoteInterface而不是newrmiclient.RemoteInterface。这意味着即使在客户端JAR中使用rmiproj.RemoteInterface，您仍需要对代码进行一些工作。 rmiServer必须是rmiproj.RemoteInterface类型。

RMI ClassNotFoundException

1 个答案: