java RMI HelloWorldJava RMI HelloWorld
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RMI 远程方法调用. 顾名思义就是可以像调用本地程序方法一样调用远程(其他JVM)的程序方法.
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分为3个部分:
Stub:中介,代理. 封装了远程对象的调用,客户端需要通过stub与server交流
RemoteServer,:远端服务提供者.也就是RemoteObject
Client:客户端
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代码示意:
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RemoteObject, 远程服务提供者, 我写了一个main方法,在本地6600端口启动这个服务,
想要启动服务,只要run即可
package demo2;
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import java.rmi.Naming;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.server.UnicastRemoteObject;
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publicclassRemoteEchoServerextends UnicastRemoteObject implements RemoteEcho {
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????PRotected RemoteEchoServer() throws RemoteException {
????????super();
????}
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????@Override
????public Object echo(Object object) throws RemoteException {
????????returnobject;
????}
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????publicstaticvoid main(String[] args) throws Exception {
????????RemoteEchoServer server = new RemoteEchoServer();
????????LocateRegistry.createRegistry(6600);
????????Naming.rebind("rmi://127.0.0.1:6600/RemoteEchoServer", server);
????}
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}
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Stub,代理,与RemoteObject交流均需要通过它
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package demo2;
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import java.rmi.Remote;
import java.rmi.RemoteException;
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publicinterfaceRemoteEchoextends Remote {
????Object echo(Object object) throws RemoteException;
}
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对Stub的进一步封装,即如何得到Stub对象
package demo2;
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import java.rmi.Naming;
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publicclass RemoteEchoFactory {
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????publicstatic RemoteEcho getEcho() throws Exception {
????????return (RemoteEcho) Naming.lookup("rmi://127.0.0.1:6600/RemoteEchoServer");
????}
}
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下面就是Client, server启动后,就能正常跑下面这个程序
package demo2;
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publicclass RemoteEchoClient {
????publicstaticvoid main(String[] args) throws Exception {
????????longstart = System.currentTimeMillis();
????????RemoteEcho echo = RemoteEchoFactory.getEcho();
????????System.out.println(echo.echo("kiss u"));
????????System.out.println(System.currentTimeMillis()-start);
????}
}
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Client 通过本地的Factory得到封装好的Stub, 他指向了RemoteObject, 然后就可以像调用本地方法一样直接用.
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