java中异步socket类的实现和源代码
我们知道,java中socket类一般操作都是同步进行，常常在read的时候socket就会阻塞直到有数据可读或socket连接断开的时候才返回，虽然可以设置超时返回，但是这样比较低效，需要做一个循环来不停扫描数据是否可读。看来，在同一个线程中，要是想实现异步读写不太容易。
下面介绍的这个类实现了伪异步socket通讯。基本思想就是在现有socket类的基础上进行封装，当socket连接建立成功后，立即创建一个socket数据接收线程，专门负责阻塞式的socket读取(read)，而当前线程负责数据的发送(send)。另外定义了一个接口，包括了socket的各种事件的回调。我们要实现这个接口，在接口实现类中创建异步socket对象，并且传递接口类到异步socket对象中，目的是有socket事件的时候回调我们的方法。
下面是接口：
SocketExHandler.java
package com.ly.net;
import java.net.*;
/**
* Title:
* Description:
* Copyright: Copyright (c) 2001
* Company: http://dozb.blogchina.com
* @author dozb
* @version 1.0
*/
/**
* 异步Socket Client Interface
* 使用方法：
* 1.定义类 MySocketClientEx 实现SocketExHandler接口,实现 OnReceive OnClose OnConnect 事件
* 2.在类中实现start方法 MySocketEx = new SocketEx(this,ip,port)
* 3.在类中实现stop方法 delete MySocketEx
* 4.当有数据到达时会触发OnReceive事件
* 5.当对方SOCKET关闭时会触发OnClose事件
* 6.当SOCKET建立时会触发OnConnect事件
*/
/**
* 异步Socket Server Interface
* 使用方法：
* 1.定义类 MySocketServerEx 实现SocketExHandler接口,实现 OnReceive OnListen OnClose OnAccept 事件
* 2.在类中实现start方法 MySocketEx = new ServerSocketEx(this,ip,port)
* 3.在类中实现stop方法 delete MySocketEx
* 4.当开始监听时会触发OnListen事件
* 5.当SOCKET关闭时会触发OnClose事件
* 6.当有客户端SOCKET要建立连接时会触发OnAccept事件
*/
public interface SocketExHandler
{
//当客户端sock数据到达时触发
public void OnReceive(Object socket,byte buf[],int nLen);
//当客户端sock连接建立成功时触发
public void OnConnect(Object socket);
//当服务端sock监听开始时触发
public void OnListen(Object socket);
//当服务端sock接受一个新的sock连接时触发
public void OnAccept(Object socket,SocketEx ClientSocket) ;
//当sock关闭时触发
public void OnClose(Object socket);
}
下面是异步客户端socket类：
SocketEx.java
package com.ly.net;
import java.io.*;
import java.net.*;
import java.util.*;
import com.ly.net.SocketExHandler;
/**
* Title:
* Description:
* Copyright: Copyright (c) 2001
* Company: http://dozb.blogchina.com
* @author dozb
* @version 1.0
*/
public class SocketEx implements Runnable
{
public static final boolean isdebug = true;//调试
/**
*构造函数.
*/
public SocketEx(SocketExHandler seh,Socket ClientSocket){this.seh = seh;thisSocket = ClientSocket; InitNotify();}
public SocketEx(SocketExHandler seh,String host,int port) throws IOException {this.seh = seh;thisSocket = new Socket(host,port);InitNotify();}
public SocketEx(SocketExHandler seh, InetAddress address, int port ) throws IOException {this.seh = seh;thisSocket = new Socket(address, port);InitNotify();}
public SocketEx(SocketExHandler seh, String host, int port, InetAddress localAddr, int localPort ) throws IOException {this.seh = seh;thisSocket = new Socket(host,port,localAddr,localPort );InitNotify();}
public SocketEx(SocketExHandler seh, InetAddress address, int port, InetAddress localAddr, int localPort ) throws IOException {this.seh = seh;thisSocket = new Socket(address, port, localAddr,localPort );InitNotify();}
/**
* 实现Socket的可见方法.
*/
public synchronized void close() throws IOException {IsRunning = false;thisSocket.close();}
public InetAddress getInetAddress() {return thisSocket.getInetAddress();}
public InputStream getInputStream() throws IOException{ return thisSocket.getInputStream(); }
public InetAddress getLocalAddress() { return thisSocket.getLocalAddress() ; }
public int getLocalPort() { return thisSocket.getLocalPort() ; }
public OutputStream getOutputStream() throws IOException{return thisSocket.getOutputStream(); }
public int getPort() { return thisSocket.getPort() ; }
public int getSoLinger() throws SocketException{ return thisSocket.getSoLinger(); }
public synchronized int getSoTimeout() throws SocketException { return thisSocket.getSoTimeout(); }
public boolean getTcpNoDelay() throws SocketException { return thisSocket.getTcpNoDelay(); }
public void setSoLinger( boolean on, int val ) throws SocketException { thisSocket.setSoLinger(on,val); }
public synchronized void setSoTimeout( int timeout ) throws SocketException {thisSocket.setSoTimeout( timeout ) ; }
public void setTcpNoDelay( boolean on ) throws SocketException {thisSocket.setTcpNoDelay(on); }
public String toString() { return thisSocket.toString() ; }
/**
* 获取Socket
*/
public Socket GetSocket(){return thisSocket;}
/**
* 初始化异步Socket
*/
private void ShowMsg(String Msg)
{
if(isdebug)
System.out.println(Msg);
}
private void InitNotify()
{
if(NotifyThread != null) return ;
try{
biStream = new BufferedInputStream(getInputStream());
thisSocket.setSoTimeout(0);
}catch(IOException e){
ShowMsg("InitNotify() IOException.");
}
IsRunning = true;
NotifyThread = new Thread(this,"SocketEx_NoitfyThread");
NotifyThread.setDaemon(true);
NotifyThread.start();
if(seh !=null)
seh.OnConnect(this);
}
/**
* 关闭Socket
*/
private void Close()
{
try{
close();
}catch(Exception eclose){
ShowMsg("Close() Exception.");
}
}
protected void finalize() throws Throwable
{
Close();
super.finalize();
}
/**
* Thread 运行
*/
public void run()
{
while(IsRunning){
try{
if(getInputStream().read(buf,0,1) <= 0)//试读一个字节
{
DoClose();
return ;
}
if(!DoReceive(getInputStream().available()))
return ;
}catch(Exception e){
ShowMsg("run() Exception.");
DoClose();
return ;
}
try{
Thread.sleep(0); //
}catch(InterruptedException e){
ShowMsg("run() InterruptedException.");
DoClose();
return ;
}
}
}
/**
* 当有数据到达时的回调方法.
*/
private boolean DoReceive(int nCanReadCount)
{
try{
int len = 0,nCurrReadCount=0,nStart=1;
do{
for(int i=nStart;i< BUFLEN;i++)
buf[i]=0;
if(nCanReadCount == 0)
{
if(seh !=null)
seh.OnReceive(this,buf,nStart);
return true;
}
if(nCanReadCount >(BUFLEN-2))
{
nCurrReadCount = BUFLEN-2;
}
else
{
nCurrReadCount = nCanReadCount;
}
len = biStream.read(buf,nStart,nCurrReadCount);
if(len == 0)
{
DoClose();
return false;
}
nCanReadCount -= len;
buf[len+nStart] = 0;
if(seh !=null)
seh.OnReceive(this,buf,len+nStart);
nStart = 0;
}while(nCanReadCount >0);
}catch(Exception excpt){
ShowMsg("DoReceive() Exception.");
DoClose();
return false;
}
return true;
}
/**
* 当Socket建立连接时的回调方法.
*/
private void DoConnect()
{
if(seh !=null)
seh.OnConnect(this);
}
/**
* 当Socket关闭时的回调方法.
*/
private void DoClose()
{
try{
if(IsRunning)
{
Close();
if(seh !=null)
seh.OnClose(this);
IsRunning = false;
}
}catch(Exception e){
ShowMsg("DoClose() Exception.");
}
}
/**
* 以下实现不要改动!!!!
*/
private Thread NotifyThread=null;
private boolean IsRunning = false;
private Socket thisSocket = null;
private static final int BUFLEN = 4097;
private byte buf[] = new byte[BUFLEN];
private BufferedInputStream biStream = null;
private SocketExHandler seh=null;
}
下面是异步socketserver类：
ServerSocketEx .java
package com.ly.net;
import java.io.*;
import java.net.*;
import java.util.*;
/**
* Title:
* Description:
* Copyright: Copyright (c) 2001
* Company: http://dozb.blogchina.com
* @author dozb
* @version 1.0
*/
public class ServerSocketEx extends ServerSocket implements Runnable
{
/**
* 以下实现不要改动!!!!
*/
public ServerSocketEx(SocketExHandler seh, int port ) throws IOException {super(port);this.seh = seh; Listen();}
public ServerSocketEx(SocketExHandler seh, int port, int backlog ) throws IOException {super(port,backlog);this.seh = seh; Listen();}
public ServerSocketEx(SocketExHandler seh, int port, int backlog, InetAddress bindAddr ) throws IOException {super(port,backlog, bindAddr);this.seh = seh;Listen();}
public void setTimeout(int timeout) {
this.timeout = timeout;
}
public static Vector GetClientPool(){return ClientPool;};
public static void CloseAllClients(){
for(int i=0;i< ClientPool.size();i++)
{
try{
SocketEx s=(SocketEx)ClientPool.elementAt(i);
if(s != null) s.close();
}catch(Exception e){}
}
ClientPool.removeAllElements();
}
public static void PutClient(SocketEx s){ClientPool.addElement(s);};
/**
* 关闭Socket
*/
public void Close()
{
IsRunning = false;
try{
close();
}catch(Exception eclose){
}
}
protected void finalize() throws Throwable
{
Close();
super.finalize();
}
/**
* Thread 运行
*/
public void run()
{
while(IsRunning){
acceptConnections();
}
DoClose();
}
// -------------------- Private methods
private void Listen() throws IOException
{
InitNotify();
if(seh !=null)
seh.OnListen(this);
}
/**
* 初始化异步Socket
*/
private void InitNotify()throws IOException
{
if(NotifyThread != null) return ;
try{
setSoTimeout(this.timeout);
} catch( IOException ex ) {
IsRunning=false;
throw ex;
}
IsRunning = true;
NotifyThread = new Thread(this,"ServerSocketEx_NoitfyThread");
NotifyThread.setDaemon(true);
NotifyThread.start();
}
/**
* 当Socket关闭时的回调方法.
*/
private void DoClose()
{
try{
if(seh !=null)
seh.OnClose(this);
//NotifyThread.stop();
}catch(Exception e){
}
}
private void processSocket(Socket s) throws IOException
{
SocketEx se = new SocketEx(seh,s);
PutClient(se);
if(seh !=null)
seh.OnAccept(this,se);
}
private void acceptConnections() {
try {
if(IsRunning == false)
return;
Socket socket = acceptSocket();
if(IsRunning != false && socket != null) {
processSocket(socket);
}
} catch(Throwable e) {
IsRunning = false;
}
}
private Socket acceptSocket() {
Socket accepted = null;
try {
if(IsRunning == true) {
accepted = accept();
if(IsRunning == false) {
if(null != accepted) {
accepted.close(); // rude, but unlikely!
accepted = null;
}
}
}
} catch(InterruptedIOException iioe) {
// normal part -- should happen regularly so
// that the endpoint can release if the server
// is shutdown.
// you know, i really wish that there was a
// way for the socket to timeout without
// tripping an exception. Exceptions are so
// 'spensive.
} catch (SocketException e) {
if (IsRunning != false) {
IsRunning = false;
}
} catch(Throwable e) {
IsRunning = false;
}
return accepted;
}
private static final int TIMEOUT = 5000;
private int timeout = TIMEOUT;
private Thread NotifyThread=null;
private boolean IsRunning=false;
private SocketExHandler seh=null;
private static Vector ClientPool=new Vector();
}
下面是几个工具类：
TimerClient.java
package com.ly.util;
/**
* TimerClient Interface
*
* @version 1.0, 8 October 1995
*
*/
public interface TimerClient
{
void timerEvent(int id);
}
TimerCtl.java
package com.ly.util;
import java.util.Vector;
import java.util.Enumeration;
//import com.borland.jb.util.Diagnostic;
/**
* Timer Component
*
* Note:
* - The successful operation of this timer requires clients to execute simple, short
* code snippets when called back by the engine. Otherwise the queue's delivery
* mechanism will be held up
*
* Further work:
* - When Thread.Interrupt is implemented we can switch from the busy wait model to
* the calculated wait model. Without the interrupt the thread waits for the
* calculated interval before waking up. This is a problem if another shorter
* request arrives. For now we'll assume the minimum resolution of the timer is
* 100ms.
*
* @version 1.0, 2 October 1995
*
*/
public class TimerCtl
{
static TimerTasks timerTasks;
public TimerCtl() {
}
/*
* Start a timer running
*/
public static void startTimer(TimerClient client, int eventId, long delay, boolean repeat) {
// create the timer if necessary
if (timerTasks == null) {
timerTasks = new TimerTasks();
timerTasks.start();
}
//Diagnostic.out.println("TIMER: startTimer"+eventId);
// add the new task to the queue
timerTasks.add(client, eventId, delay, repeat);
}
/*
* Stop a timer
*/
public static void stopTimer(TimerClient client, int eventId) {
//Diagnostic.out.println("TIMER: stopTimer"+eventId);
if(timerTasks != null)
timerTasks.end(client, eventId);
}
}
class TimerTasks extends Thread
{
Vector tasks = new Vector();
boolean suspended = false;
boolean sleeping = false;
/**
* Thread task runner
*/
public void run() {
// Loop forever
while (true) {
long sleepTime = 0;
// Ensure that the tasks class is protected
synchronized (tasks) {
//Diagnostic.out.println("TIMER: Tick");
// Scan the job list for any jobs which may fire.
// Mark one-shot jobs for deletion
// Calculate the maximum time we can sleep for
sleepTime = scan();
// Delete DeletePending jobs. DeletePending jobs result from one-shots which have
// been sent, and repeat jobs which have been cancelled. Jobs may have been
// cancelled during the Scan process.
purge();
}
// Suspend timer if necessary
if (tasks.size() == 0) {
//Diagnostic.out.println("TIMER: Suspend");
try {
synchronized(this) {
suspended = true;
wait();
}
}
catch (InterruptedException e) {
}
}
else {
//Diagnostic.out.println("TIMER: Suggested Sleeping for "+sleepTime);
if (sleepTime >= 0) {
try {
sleeping = true;
sleep(sleepTime);
sleeping = false;
}
catch (InterruptedException i) {
//Diagnostic.out.println("TIMER: Caught me napping");
}
}
}
}
}
/**
* Add a new task
*/
public void add(TimerClient client, int eventId, long delay, boolean repeat) {
TimerTask t = new TimerTask(client, eventId, delay, repeat);
synchronized (tasks) {
tasks.addElement((Object)t);
}
// Want instant response - wake the thread if it's napping
// unfortunately the interrupt() method is not working
// if (sleeping)
// interrupt();
if (suspended) {
synchronized(this) {
notify();
//Diagnostic.out.println("TIMER: Resume");
suspended = false;
}
}
}
/**
* Find the job and mark it for deletion
*/
public void end(TimerClient client, int eventId) {
synchronized (tasks) {
for (int i = 0; i < tasks.size(); i++) {
TimerTask t = (TimerTask)tasks.elementAt(i);
//if (!t.deletePending && t.client == client && t.eventId == eventId)
if (t.deletePending == false && t.client == client && t.eventId == eventId) {
// JPBS - if we don't reset 'repeat', deletePending will be set again
t.repeat = false;
t.deletePending = true;
break;
}
}
}
}
/**
* Clear out all the dead wood
*/
void purge() {
for (int i = 0; i < tasks.size(); i++) {
TimerTask t = (TimerTask)tasks.elementAt(i);
if (t.deletePending) {
//Diagnostic.out.println("TIMER: purged");
tasks.removeElementAt(i);
i--;
}
}
}
long scan() {
// The value added to the current time determines the MAX time until
// the next scan
// This is 100 now since thread.interrupt() is not implemented
long nextTime = System.currentTimeMillis() + 100;
for (int i = 0; i < tasks.size(); i++) {
TimerTask t = (TimerTask)tasks.elementAt(i);
// if not already deletePending, test (and possibly send the event)
// as a result, the job may be flagged for deletion.
// May also be a non-repeating job and so require self deletion
if (!t.deletePending)
t.test();
// if the task didn't get deleted - see what it contributes to the time
if (!t.deletePending)
nextTime = Math.min(nextTime, t.timeNext);
//Diagnostic.out.println("TIMER: Scanning "+t.eventId+" "+(t.deletePending == true ? "DEL" : ""));
}
return nextTime - System.currentTimeMillis();
}
}
class TimerTask
{
TimerClient client;
int eventId;
long timePrev;
long timeDelay;
long timeNext;
boolean repeat;
boolean deletePending;
public TimerTask(TimerClient client, int eventId, long timeDelay, boolean repeat) {
this.client = client;
this.eventId = eventId;
this.timeDelay = timeDelay;
this.repeat = repeat;
// schedule the next click - now + delay
timeNext = System.currentTimeMillis() + timeDelay;
deletePending = false;
//Diagnostic.out.println("TIMER: Adding New Task");
}
public void test() {
if (System.currentTimeMillis() >= timeNext) {
//Diagnostic.out.println("TIMER: fire");
// Fire the event
client.timerEvent(eventId);
// Update the next time
timeNext = System.currentTimeMillis() + timeDelay;
deletePending = !repeat;
}
}
}
下面是使用上面的异步socket类，做的demo开发
DemoAppSocketHandler.java
package com.ly.net;
import java.net.*;
import java.util.*;
/**
* Title:
* Description:
* Copyright: Copyright (c) 2001
* Company: http://dozb.blogchina.com
* @author dozb
* @version 1.0
*/
public interface DemoAppSocketHandler
{
//当客户端sock有数据到达时触发
public void OnProcessCmd(Object socket,String FromArea,String ToArea,String ChannNo,String MainFun,String SubFun,Vector ParamList);
//当客户端sock连接建立成功时触发
public void OnConnect(Object socket);
//当服务端sock监听开始时触发
public void OnListen(Object socket);
//当服务端sock接受一个新的sock连接时触发
public void OnAccept(Object socket,SocketEx ClientSocket) ;
//当sock关闭时触发
public void OnClose(Object socket);
}
DemoAppSocket.java
package com.ly.net;
import java.io.*;
import java.util.*;
import com.ly.util.*;
/**
* Title:
* Description:
* Copyright: Copyright (c) 2001
* Company: http://dozb.blogchina.com
* @author dozb
* @version 1.0
*/
//这个类是异步socket 客户端和服务端的使用演示
//对于客户端，实现了断开后自动连接
//这个类是SocketExHandler 和 TimerClient 接口的实现
public class DemoAppSocket implements SocketExHandler,TimerClient{
//Sock构造函数
public DemoAppSocket(DemoAppSocketHandler issh,boolean isServer,String ip,int port) {
this.issh = issh;
this.isServer = isServer;
this.ip = ip;
if(this.ip == null) this.ip = "";
this.port = port;
if(this.port <0) this.port = 0;
}
//调用完构造后调用这个函数创建sock对象
public void create()
{
if(!start())
TimerCtl.startTimer(this,eventId,30*1000,true);
}
//这个方法一般不需要直接调用
public boolean start()
{
if(this.isServer) return startServer(); else return startClient();
}
//停止socket
public void stop()
{
TimerCtl.stopTimer(this,eventId);
if(this.isServer) stopServer(); else stopClient();
}
//发送socket消息
public boolean SendCmd(Object socket,String strCmd)
{
SocketEx currSocketEx = (SocketEx)socket;
if(!isServer && currSocketEx==null) currSocketEx = socketEx;
if(currSocketEx == null) return false;
try{
PrintWriter Sender = new PrintWriter(currSocketEx.getOutputStream(),true);
Sender.print(strCmd);
Sender.flush();
return true;
}catch(Exception e)
{
return false;
}
}
//发送socket消息
public boolean SendCmd(Object socket,String FromArea,String ToArea,String ChannNo,String MainFun,String SubFun,String Param)
{
String strCmd = FromArea + ToArea + ChannNo + MainFun+SubFun+"&"+Param+"&";
return SendCmd(socket,strCmd);
}
//获得IP地址
public String getIp()
{
return ip;
}
//获得端口号
public int getPort()
{
return port;
}
protected boolean startClient()
{
if(socketEx != null) {
try{
socketEx.close();
}catch(IOException e){};
socketEx = null;
}
try{
socketEx = new SocketEx(this,ip,port);
TimerCtl.stopTimer(this,eventId);
return true;
}catch(IOException e)
{
socketEx = null;
}
return false;
}
protected boolean startServer()
{
if(serverSocketEx != null) {
try{
serverSocketEx.close();
}catch(IOException e){};
serverSocketEx = null;
}
try{
serverSocketEx = new ServerSocketEx(this,port);
TimerCtl.stopTimer(this,eventId);
return true;
}catch(IOException e)
{
serverSocketEx = null;
}
return false;
}
protected void stopServer()
{
if(serverSocketEx != null) {
try{
serverSocketEx.close();
}catch(IOException e){};
serverSocketEx = null;
}
}
protected void stopClient()
{
if(socketEx != null) {
try{
socketEx.close();
}catch(IOException e){};
socketEx = null;
}
}
public void timerEvent(int id)
{
start();
}
static public String[] DealStr(String strS)
{
int CMDHEAD_LEN = 22;
String[] ret = new String[2];//0留下的字符串1完整的CMD
ret[0]=strS;//
//假如只有一个&或没有&则不完整
int FirstPos=strS.indexOf("&");
if(FirstPos==-1)
return ret;
if(FirstPos != CMDHEAD_LEN-1)
{
strS = strS.substring(FirstPos+1);
return DealStr(strS);
}
int nSecondPos = strS.indexOf("&",FirstPos+1);
if(nSecondPos<0)
return ret;
//可能格式不正确了
if(strS.length()< CMDHEAD_LEN)
return ret;
ret[1] = strS.substring(0,nSecondPos+1);
ret[0]=strS.substring(nSecondPos+1);
return ret;
}
public void OnReceive(Object socket,byte buf[],int nLen){
String ReceiveBuff = sReceiveBuf + (new String(buf,0,nLen));
do//分解成单个的命令串
{
String strCmd[] = DealStr(ReceiveBuff);
ReceiveBuff = strCmd[0];
if(strCmd[1]==null || strCmd[1].equals("")) break;
System.out.println(strCmd[1]);
String FromArea=strCmd[1].substring(0,6);
String ToArea=strCmd[1].substring(6,12);
String ChannNo=strCmd[1].substring(12,15);
String MainFun=strCmd[1].substring(15,18);
String SubFun=strCmd[1].substring(18,21);
String Param =strCmd[1].substring(22,strCmd[1].length()-1);
Vector ParamList=new Vector();
int nLastPos=0;
while(true)
{
int nPos = Param.indexOf(",",nLastPos);
if(nPos <0)
{
ParamList.add(Param.substring(nLastPos));
// System.out.println(Param.substring(nLastPos));
break;
}
String sParam = Param.substring(nLastPos,nPos);
ParamList.add(sParam);
// System.out.println(sParam);
nLastPos = nPos+1;
}
DoProcessCmd(socket,FromArea,ToArea,ChannNo,MainFun,SubFun,ParamList);
}while(true);
sReceiveBuf = ReceiveBuff;
if(sReceiveBuf == null) sReceiveBuf=null;
}
protected void DoProcessCmd(Object socket,String FromArea,String ToArea,String ChannNo,String MainFun,String SubFun,Vector ParamList)
{
if(issh !=null)
issh.OnProcessCmd(socket,FromArea,ToArea,ChannNo,MainFun, SubFun, ParamList);
}
public void OnConnect(Object socket)
{
if(issh !=null) issh.OnConnect(socket);
}
public void OnListen(Object socket){
if(issh !=null) issh.OnListen(socket);
}
public void OnAccept(Object socket,SocketEx ClientSocket) {
if(issh !=null) issh.OnAccept(socket,ClientSocket);
}
public void OnClose(Object socket){
notifyAll();
TimerCtl.startTimer(this,eventId,30*1000,true);
if(issh !=null) issh.OnClose(socket);
}
//Socket
SocketEx socketEx = null;
ServerSocketEx serverSocketEx=null;
final int eventId = 1;
String sReceiveBuf="";
DemoAppSocketHandler issh=null;
boolean isServer=false;
String ip="127.0.0.1";
int port=20000;
}
通过这种方式，可以高效地使用socket通讯，在异步socket版本没有发布以前，不失是一种解决问题的方法。:)