Java Web项目中使用Socket通信多线程、长连接的方法

很多时候在javaweb项目中我们需要用到socket通信来实现功能，在web中使用socket我们需要建立一个监听程序，在程序启动时，启动socket监听。我们的应用场景是在java项目中，需要外接如一个硬件设备，通过tcp通信，获取设备传上来的数据，并对数据做回应。

先看一下web的监听代码：

import javax.servlet.servletcontextevent;
import javax.servlet.servletcontextlistener;
public class attendsocetlistener implements servletcontextlistener{
private socketthread socketthread;
public void contextdestroyed(servletcontextevent arg) { 
if(null!=socketthread && !socketthread.isinterrupted()) 
{ 
socketthread.closesocketserver(); 
socketthread.interrupt(); 
} 
} 
@override 
public void contextinitialized(servletcontextevent arg) { 
// todo auto-generated method stub 
if(null==socketthread) 
{ 
//新建线程类 
socketthread=new socketthread(null); 
//启动线程 
socketthread.start(); 
} 
} 
}

创建线程：

import java.io.ioexception;
import java.net.serversocket;
import java.net.socket;
import java.util.arraylist;
import java.util.list;
public class socketthread extends thread
{
private serversocket serversocket = null; 
public socketthread(serversocket serverscoket){ 
try { 
if(null == serversocket){ 
this.serversocket = new serversocket(); 
system.out.println("socket start"); 
} 
} catch (exception e) { 
system.out.println("socketthread创建socket服务出错"); 
e.printstacktrace(); 
} 
} 
public void run(){ 
while(true){ 
try { 
if(serversocket==null){
break;
}else if(serversocket.isclosed()){
break;
}
socket socket = serversocket.accept(); 
if(null != socket && !socket.isclosed()){ 
//处理接受的数据 
thread t = new thread(new socketoperate(socket)); 
t.start(); 
}else{
break;
}
}catch (exception e) { 
system.out.println("socketthread创建socket服务出错"); 
e.printstacktrace(); 
} 
} 
} 
public void closesocketserver(){ 
try { 
if(null!=serversocket && !serversocket.isclosed()) 
{ 
serversocket.close(); 
} 
} catch (ioexception e) { 
// todo auto-generated catch block 
e.printstacktrace(); 
} 
} 
}

处理接受到的数据：

import java.io.bufferedreader;
import java.io.ioexception;
import java.io.inputstreamreader;
import java.io.outputstream;
import java.net.socket;
public class socketoperate implements runnable { 
private socket socket; 
//该线程所处理的socket所对应的输入流 
bufferedreader br = null; 
string str = null; 
string content = null; 
inputstreamreader reader=null; 
public socketoperate(socket socket) throws ioexception 
{ 
this.socket = socket; 
reader = new inputstreamreader(this.socket.getinputstream(),"utf-"); 
br = new bufferedreader(reader); 
} 
@override 
public void run() 
{ 
try 
{ 
// 采用循环不断从socket中读取客户端发送过来的数据 
while (true) 
{ 
content = readfromclient(); 
system.out.println(content);
if (content == null) 
{ 
break; 
} 
outputstream os = socket.getoutputstream(); 
os.write(("res, ok,<年班,小明>, ,#" + "\n").getbytes("utf-")); 
os.flush();
} 
} 
catch (ioexception e) 
{ 
e.printstacktrace(); 
} 
} 
//定义读取客户端数据的方法 
private string readfromclient() 
{ 
try 
{ 
str = br.readline(); 
return str; 
} 
//如果捕捉到异常，表明该socket对应的客户端已经关闭 
catch (ioexception e) 
{ 
try {
br.close();
reader.close();
socket.close();
} catch (ioexception e) {
// todo auto-generated catch block
e.printstacktrace();
} 
} 
return null; 
} 
}

客户端代码：

package
import java.io.*;
import java.net.*;
public class talkclient {
public static void main(string args[]) throws unknownhostexception, ioexception {
socket socket=new socket("...",);
printwriter os=new printwriter(socket.getoutputstream());
bufferedreader is=new bufferedreader(new inputstreamreader(socket.getinputstream()));
int i=;
while(socket.isconnected()){
os.print("beat,,,,.,,#"+"\n");
os.flush();
system.out.println("client:"+i);
system.out.println("server:"+is.readline());
i++;
} 
//继续循环
os.close(); //关闭socket输出流
is.close(); //关闭socket输入流
socket.close(); //关闭socket
}
}

以上所述是小编给大家介绍的java web项目中使用socket通信多线程、长连接的方法，希望对大家有所帮助！