简单的RMI远程调用框架架实现

来源：互联网发布：excel 示例数据编辑：程序博客网时间：2024/05/16 07:56

随着服务器的压力不断的上升，rmi的重要性日益突出

今天就简单的剖析以下RMI的底层实现原理

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（1）rmi调用承载对象：call

import java.io.*;public class Call implements Serializable{  private String className;  //表示类名  private String methodName; //表示方法名  private Class[] paramTypes; //表示方法参数类型  private Object[] params; //表示方法参数值  private Object result;  //表示方法的返回值或者方法抛出的异常    public Call(){}  public Call(String className,String methodName,Class[] paramTypes,                            Object[] params){    this.className=className;    this.methodName=methodName;    this.paramTypes=paramTypes;    this.params=params;  }    public String getClassName(){return className;}  public void setClassName(String className){this.className=className;}  public String getMethodName(){return methodName;}  public void setMethodName(String methodName){this.methodName=methodName;}  public Class[] getParamTypes(){return paramTypes;}  public void setParamTypes(Class[] paramTypes){this.paramTypes=paramTypes;}  public Object[] getParams(){return params;}  public void setParams(Object[] params){this.params=params;}  public Object getResult(){return result;}  public void setResult(Object result){this.result=result;}  public String toString(){    return "className="+className+" methodName="+methodName;  }}

（2）客户端执行rmi调用

import java.io.*;import java.net.*;import java.util.*;public class SimpleClient {  public void invoke()throws Exception{    Socket socket = new Socket("localhost",8000);    OutputStream out=socket.getOutputStream();    ObjectOutputStream oos=new ObjectOutputStream(out);    InputStream in=socket.getInputStream();    ObjectInputStream ois=new ObjectInputStream(in);     //Call call=new Call("remotecall.HelloService","getTime",new Class[]{},new Object[]{});    Call call=new Call("remotecall.HelloService","echo",new Class[]{String.class},new Object[]{"Hello"});     oos.writeObject(call);    call=(Call)ois.readObject();     System.out.println(call.getResult());    ois.close();    oos.close();    socket.close();  }  public static void main(String args[])throws Exception {    new SimpleClient().invoke();   }}

（服务器端更具call对象的相关信息，通过反射调用方法，并将结果返回给客户端）

import java.io.*;import java.net.*;import java.util.*;import java.lang.reflect.*;public class SimpleServer {  private Map remoteObjects=new HashMap();    public void register(String className,Object remoteObject){    remoteObjects.put( className,remoteObject);  }   public void service()throws Exception{    ServerSocket serverSocket = new ServerSocket(8000);    System.out.println("服务器启动.");    while(true){      Socket socket=serverSocket.accept();      InputStream in=socket.getInputStream();      ObjectInputStream ois=new ObjectInputStream(in);      OutputStream out=socket.getOutputStream();      ObjectOutputStream oos=new ObjectOutputStream(out);      Call call=(Call)ois.readObject();      System.out.println(call);      call=invoke(call);      oos.writeObject(call);            ois.close();      oos.close();      socket.close();    }  }  public Call invoke(Call call){    Object result=null;    try{      String className=call.getClassName();      String methodName=call.getMethodName();      Object[] params=call.getParams();      Class classType=Class.forName(className);       Class[] paramTypes=call.getParamTypes();      Method method=classType.getMethod(methodName,paramTypes);        Object remoteObject=remoteObjects.get(className);------>>>至于这边为什么不用class  newInstance得到一个新对象————>>>必须式注册的组件才能被访问      if(remoteObject==null){        throw new Exception(className+"的远程对象不存在");      }else{        result=method.invoke(remoteObject,params);      }    }catch(Exception e){result=e;}    call.setResult(result);    return call;  }  public static void main(String args[])throws Exception {    SimpleServer server=new SimpleServer();    server.register("remotecall.HelloService",new HelloServiceImpl());    server.service();  }}

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