远程对象不支持RMI方法：java.rmi.UnmarshalException：无法识别的方法哈希

Question

我的银行 - 客户端（服务器客户端通过RMI）应用程序出现了一个奇怪的问题。

我有实现IBank的Bank类扩展了Remote。这个Bank Class有几种方法，checkClient，getBankAccount等。

问题是，我可以从客户端调用方法checkClient（boolean）就好了，所有其他方法都给出了UnmarshalException

服务器端的银行课程：

public class Bank extends UnicastRemoteObject implements IBank { 

    private BankName bankName;

    private String URL;

    @Override
    public boolean checkClient(String username, String password) {
        Client client = db.getClient(username, password);

        if(client.getUsername() == null && client.getPassword() == null){
        System.out.println("Client not found in " + getBankName() + "database");
            return false;
        }

        System.out.println(client.toString() + " connected to bank succesfully");

        return true;
    }

    @Override
    public ArrayList<BankAccount> getAccounts(Client c) throws RemoteException {
       System.out.println("WORKED");
       return null;
    }
}

银行类实现的接口：

public interface IBank extends Remote{

    String getURL() throws RemoteException;

    String getBankName() throws RemoteException;

    boolean checkClient(String Username, String Password) throws RemoteException;

    ArrayList<BankAccount> getAccounts(Client c) throws RemoteException;
}

Bankmethod使用的可序列化对象：

public class BankAccount implements Serializable {

}

*以上示例仅是完整应用程序的一部分

我无法弄清楚为什么'checkClient'方法工作得很好，并且getAccounts（以及上面代码中未包含的其他方法）给出了UnmarshalException。

非常感谢任何帮助

示例

您可以在下面找到我用于将客户端连接到银行的方法：

@Override
public

ArrayList<BankAccount> connectToBank(Client c) throws RemoteException {
    assert(c != null);

    ArrayList<BankAccount> accounts;        

    if(!Bank.checkClient(c.Username, c.Password)){
        System.out.println("bank.checkclient == false, Client not found");
        return null;
    } else {
        System.out.println("Client found in " + Bank.getBankName() + " database");
    }

    System.out.println("Calling bank.getaccounts");
    accounts = Bank.getAccounts(c);

    if(accounts == null){
        System.out.println("No accounts found for " + c.Username);
    }

    return accounts;        
}

当我使用不存在的用户名和密码时，控制台打印出来：

Server IP Address: localhost
Server Port number 9000
Client: Registry located
Client: Bank and Publisher are bound
bank.checkclient == false, Client not found

并返回null;

但是当我使用确实存在的用户名和密码时，控制台会打印出来：

Server IP Address: localhost
Server Port number 9000
Client: Registry located
Client: Bank and Publisher are bound
Client found in RABO database
Calling bank.getaccounts
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1774)
    at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
    at javafx.event.Event.fireEvent(Event.java:198)
    at javafx.scene.Node.fireEvent(Node.java:8411)
    at javafx.scene.control.Button.fire(Button.java:185)
    at com.sun.javafx.scene.control.behavior.ButtonBehavior.keyReleased(ButtonBehavior.java:136)
    at com.sun.javafx.scene.control.behavior.ButtonBehavior.callAction(ButtonBehavior.java:106)
    at com.sun.javafx.scene.control.behavior.BehaviorBase.callActionForEvent(BehaviorBase.java:218)
    at com.sun.javafx.scene.control.behavior.BehaviorBase.lambda$new$74(BehaviorBase.java:135)
    at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
    at javafx.event.Event.fireEvent(Event.java:198)
    at javafx.scene.Scene$KeyHandler.process(Scene.java:3964)
    at javafx.scene.Scene$KeyHandler.access$1800(Scene.java:3910)
    at javafx.scene.Scene.impl_processKeyEvent(Scene.java:2040)
    at javafx.scene.Scene$ScenePeerListener.keyEvent(Scene.java:2501)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:197)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:147)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleKeyEvent$353(GlassViewEventHandler.java:228)
    at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleKeyEvent(GlassViewEventHandler.java:227)
    at com.sun.glass.ui.View.handleKeyEvent(View.java:546)
    at com.sun.glass.ui.View.notifyKey(View.java:966)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1771)
    ... 49 more
Caused by: java.rmi.ServerException: RemoteException occurred in server thread; nested exception is: 
    java.rmi.UnmarshalException: unrecognized method hash: method not supported by remote object
    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:354)
    at sun.rmi.transport.Transport$1.run(Transport.java:200)
    at sun.rmi.transport.Transport$1.run(Transport.java:197)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.Transport.serviceCall(Transport.java:196)
    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$256(TCPTransport.java:683)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
    at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:276)
    at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:253)
    at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:162)
    at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:227)
    at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:179)
    at com.sun.proxy.$Proxy7.getAccounts(Unknown Source)
    at Client.Client.connectToBank(Client.java:240)
    at Client.FXMLClientController.btnLogIn_clicked(FXMLClientController.java:232)
    ... 59 more
Caused by: java.rmi.UnmarshalException: unrecognized method hash: method not supported by remote object
    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:294)
    at sun.rmi.transport.Transport$1.run(Transport.java:200)
    at sun.rmi.transport.Transport$1.run(Transport.java:197)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.Transport.serviceCall(Transport.java:196)
    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$256(TCPTransport.java:683)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    ... 1 more

所以你可以看到Bank.checkClient工作正常，Bank.getAccounts导致问题

Answer 1

您已经改变了有关远程接口的内容，而无需重新编译和重新部署所有内容。做一个干净的构建，重新部署，重新测试。

Answer 2

我仍然没有找到确切的问题，但是当我尝试通过RMI发送自定义对象时，问题就出现了。从Bank返回String，boolean，int等的方法工作正常。当我尝试发送BankAccount（customobject）时，出现了问题。

我通过将Client-project和Bank-project合并在一起来修复它，现在他们使用完全相同的接口和类，因此Unmarshal问题消失了

希望这有助于某人