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!