Question

我正在编写一个小型Java RMI服务器和客户端程序。我花了一些时间试图弄清楚错误信息但没有成功。

客户端生成以下错误：

尝试连接到：127.0.0.1：3232 错误!!!：StockClient：main：无法连接到服务器：java.rmi.UnmarshalException：错误解组返回标头;嵌套例外是： java.rmi.UnmarshalException：错误解组返回标头;嵌套异常是： java.io.EOFException的 java.io.EOFException的 at sun.rmi.transport.StreamRemoteCall.executeCall（StreamRemoteCall.java:209） at sun.rmi.server.UnicastRef.invoke（UnicastRef.java:359） at sun.rmi.registry.RegistryImpl_Stub.lookup（Unknown Source）在StockClient.StockClient.main（StockClient.java:44）引起：java.io.EOFException at java.io.DataInputStream.readByte（DataInputStream.java:250） at sun.rmi.transport.StreamRemoteCall.executeCall（StreamRemoteCall.java:195） ......还有3个

仅在客户端尝试连接时，服务器才会出现以下错误。

此地址= localhost / 127.0.0.1，port = 3232 线程“RMI TCP连接（空闲）”中的异常java.security.AccessControlException：访问被拒绝（java.net.SocketPermission 127.0.0.1:62586接受，解决） at java.security.AccessControlContext.checkPermission（AccessControlContext.java:374）在java.security.AccessController.checkPermission（AccessController.java:549）在java.lang.SecurityManager.checkPermission（SecurityManager.java:532） at java.lang.SecurityManager.checkAccept（SecurityManager.java:1157） at sun.rmi.transport.tcp.TCPTransport $ ConnectionHandler.checkAcceptPermission（TCPTransport.java:636） at sun.rmi.transport.tcp.TCPTransport.checkAcceptPermission（TCPTransport.java:275） at sun.rmi.transport.Transport $ 1.run（Transport.java:158） at java.security.AccessController.doPrivileged（Native Method） at sun.rmi.transport.Transport.serviceCall（Transport.java:155） at sun.rmi.transport.tcp.TCPTransport.handleMessages（TCPTransport.java:535） at sun.rmi.transport.tcp.TCPTransport $ ConnectionHandler.run0（TCPTransport.java:790） at sun.rmi.transport.tcp.TCPTransport $ ConnectionHandler.run（TCPTransport.java:649） at java.util.concurrent.ThreadPoolExecutor $ Worker.runTask（ThreadPoolExecutor.java:886） at java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:908）在java.lang.Thread.run（Thread.java:680）

由于服务器错误，我很确定它是安全性或注册表错误，服务器的安全策略是：

授予{ permission java.security.AllPermission; };

并使用以下参数运行

-Djava.security.policy = client.policy

我已经尝试了我能找到的所有内容，但似乎仍然在圈子里。

相关方法：

服务器：

 public static void main(String[] args)
    {//main(...) starts
        // set up the data structures and data

        //add users
        //Users hard coded as this is an example proof on concept program
        //Names and passwords not hashed for simplicity
        User alpha = new User("Alpha", "AlphaPass");
        User omega = new User("Omega", "OmegaPass");
        users.add(alpha);
        users.add(omega);

        //startup the RMI server
        try
        {
            System.setSecurityManager(new RMISecurityManager());
            StockServer server = new StockServer();
            StockServerInterface inter = (StockServerInterface)
UnicastRemoteObject.exportObject (server,0);

            // create the registry and bind the name and object.
            registry = LocateRegistry.createRegistry(thisPort);
            registry.rebind("StockServer", inter);
        }
        catch (Exception e)
        {
            System.out.println("Unable to create StockServer: " + e);
            e.printStackTrace();
            System.exit(1);
        }
    }//main(...) ends


    /**
     * Constructor for StockServer
     *
     * @throws RemoteException
     */
    public StockServer() throws RemoteException
    {

        //try to get the host machine's IP address
        try
        {
            // get the address of this host.
            thisAddress = (InetAddress.getLocalHost()).toString();
        } catch (Exception e)
        {
            throw new RemoteException("can't get inet address. " + e);
        }

        //Set the port
        thisPort = 3232;

        //Print out the server address and port
        System.out.println("this address=" + thisAddress + ",port=" + thisPort);
    }

客户端：

private static StockServerInterface stockServer;
static public void main(String args[])
{
    Registry registry;
    //get the server address from the args
    String serverAddress = args[0];

    //get the server port from the args
    String serverPort = args[1];

    //Let the user know we are about to try to connect
    System.out.println("Trying to connect to: " + serverAddress + ":" + serverPort);
    try
    {
        // get the registry
        registry = LocateRegistry.getRegistry(
                serverAddress,
                (new Integer(serverPort)).intValue());
        // look up the remote object
        stockServer = (StockServerInterface) (registry.lookup("StockServer"));


        //Authenticate the user
        authenticate();

        //setup the hashset
        HashSet<Stock> hashStockSet = null;

        //setup the hashset of desired stocks
        try
        {
            hashStockSet = getHashSet();
        } catch (IOException e)
        {
            e.printStackTrace();
            System.exit(1);
        } catch (ClassNotFoundException e)
        {
            e.printStackTrace();
            System.exit(1);
        }
        //bit of a heavy handed infinte loop so we continue to get the loop
        while(true)
        {
            //Run the ticker
            ticker(hashStockSet);
        }

        // call the remote method


    }
    catch (RemoteException e)
    {
        System.out.println("ERROR!!!: StockClient: main: Could not connect to the server: "+e);
        e.printStackTrace();
    }
    catch (NotBoundException e)
    {
        System.out.println("ERROR!!!: StockClient: main: Could not connect to the server: "+e);
        e.printStackTrace();
    }

Answer 1

除非客户端依赖代码库功能为服务器提供类，否则在RMI服务器中不需要SecurityManager。删除它，或调试.policy文件。很明显，你写的那个没有加载。

使用-Djava.security.debug=access,failure运行您的服务器，您将看到所有安全域从中获取配置的位置，以及在抛出异常时失败的域。

Java RMI客户端访问被拒绝

1 个答案: