Rmi连接被localhost拒绝

Question

我使用java rmi时遇到问题:

当我试图运行我的服务器时,我得到一个connectException(见下文).

执行重新绑定方法时发生异常:

Runtime.getRuntime().exec("rmiregistry 2020");
MyServer server = new MyServer();
Naming.rebind("//localhost:2020/RemoteDataPointHandler", server);

当使用rmi:// localhost:2020/RemoteDataPointHandler时,它也不起作用.使用默认端口也不起作用.我也尝试使用127.0.0.1 ip-address,但效果相同.

我的运行时args:

-Djava.security.policy=java.security.AllPermission

Exception in thread "main" java.rmi.ConnectException: Connection refused to host: localhost; nested exception is: 
    java.net.ConnectException: Connection refused
    at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:574)
    at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:185)
    at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:171)
    at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:306)
    at sun.rmi.registry.RegistryImpl_Stub.rebind(Unknown Source)
    at java.rmi.Naming.rebind(Naming.java:160)
    at be.fortega.knx.server.Main.(Main.java:25)
    at be.fortega.knx.server.Main.main(Main.java:16)
Caused by: java.net.ConnectException: Connection refused
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
    at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:433)
    at java.net.Socket.connect(Socket.java:524)
    at java.net.Socket.connect(Socket.java:474)
    at java.net.Socket.(Socket.java:371)
    at java.net.Socket.(Socket.java:184)
    at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:22)
    at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:128)
    at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:569)
    ... 7 more

Answer 1

有一个连接异常的simliar问题.当注册表尚未启动时(如在您的情况下)或注册表已经取消导出(如我的情况),它会被抛出.

但是对启动注册表的两种方式之间的区别进行简短评论:

Runtime.getRuntime().exec("rmiregistry 2020");

在新进程中运行javas bin-directory中的rmiregistry.exe并继续与您的java代码并行.

LocateRegistry.createRegistry(2020);

rmi方法调用启动注册表,返回对该注册表远程对象的引用,然后继续下一个语句.

在您的情况下,当您尝试绑定对象时,注册表不会及时启动

Answer 2

它似乎工作,当我更换

Runtime.getRuntime().exec("rmiregistry 2020");

通过

LocateRegistry.createRegistry(2020);

任何人都知道为什么？有什么不同？

Answer 3

rmiregistry在尝试使用它连接(注册)RMI服务之前,您需要运行.

该LocateRegistry.createRegistry(2020)方法调用创建和出口上的指定端口号的注册表.

请参阅LocateRegistry的文档