現(xiàn)在雖然我們很少用到RMI進(jìn)行編程，但是做為Java一個(gè)最早的分布式解決方案，我們還是有了解的必要，從例子開始吧（雖然是幾年前的了）！
遠(yuǎn)程接口RmiHelloRemoteIntfc .java
import java.rmi.*;
public interface RmiHelloRemoteIntfc extends Remote
{
String helloRemoteObj(String client) throws RemoteException;
}
遠(yuǎn)程接口的實(shí)現(xiàn)類RmiHelloRemoteObj.java
import java.rmi.server.*;
import java.rmi.*;
public class RmiHelloRemoteObj extends UnicastRemoteObject implements RmiHelloRemoteIntfc
{
public RmiHelloRemoteObj() throws RemoteException
{
super();
}
public String helloRemoteObj(String client) throws RemoteException
{
return "Hello World"+client;
}
}
服務(wù)器類RmiHelloServer.java
import java.io.*;
import java.rmi.*;
import java.rmi.server.*;
import sun.applet.*;
import java.rmi.registry.LocateRegistry;
public class RmiHelloServer
{
public RmiHelloServer()
{
}
public static void main(String[] args)
{
//創(chuàng)建并安裝安全管理器
if(System.getSecurityManager()==null)
{
System.setSecurityManager(new RMISecurityManager());
}
try{
//創(chuàng)建遠(yuǎn)程對(duì)象
RmiHelloRemoteObj ttt=new RmiHelloRemoteObj();
//啟動(dòng)注冊表
LocateRegistry.createRegistry(2222);
//獎(jiǎng)名稱綁定到對(duì)象
Naming.rebind("http://Fangm:2222/helloObj",ttt);
System.out.println("RMI服務(wù)器正在運(yùn)行。。。。。。");
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
服務(wù)器端的權(quán)限文件RmiHelloServer.policy
grant codeBase
"file:/e:/download/rmitest/"
{
permission java.net.SocketPermission
"*:1000-9999","accept,connect,listen,resolve";
};
現(xiàn)在就看看Client端是如何連接服務(wù)器和進(jìn)行遠(yuǎn)程方法的調(diào)用的吧
import java.rmi.*;
import java.rmi.server.*;
public class RmiHelloClient
{
public RmiHelloClient()
{
}
public static void main(String[] args)
{
//創(chuàng)建并安裝安全管理器
if(System.getSecurityManager()==null)
{
System.setSecurityManager(new RMISecurityManager());
}
try{
RmiHelloRemoteIntfc c1=(RmiHelloRemoteIntfc)Naming.lookup("rmi://Fangm:2222/helloObj");
System.out.println(c1.helloRemoteObj("Everyone"));
}
catch(Exception e)
{
e.printStackTrace();
}
System.exit(0);
}
}
Client端的權(quán)限文件RmiHelloClient.policy
grant codeBase
"file:/e:/download/rmitest/"
{
permission java.net.SocketPermission
"*:1000-9999","accept,connect,listen,resolve";
};
好了，一個(gè)最簡單的RMI例子就安無了，對(duì)了還少了最重要的一步，那就是編譯和運(yùn)行呢？我們就來了個(gè)Bat或Cmd的批處理來進(jìn)行吧，
看看RmiHello.bat吧
javac RmiHelloRemoteIntfc.java
javac RmiHelloRemoteObj.java
rmic RmiHelloRemoteObj
javac RmiHelloServer.java
javac RmiHelloClient.java
echo 在另一個(gè)窗口啟動(dòng)服務(wù)器，請稍后。。。
start java -Djava.security.policy=RmiHelloServer.policy RmiHelloServer
echo 運(yùn)行客戶程序。。。
java -Djava.security.policy=RmiHelloClient.policy RmiHelloClient
這個(gè)文件很簡單吧！包你一試就通，雖然簡單，不過對(duì)于初學(xué)者來說，還是很不錯(cuò)的哦！