The Java Web project USES the Socket communication multithreaded long connected method
- 2020-05-09 18:37:49
- OfStack
Many times in the javaweb project we need to use Socket communication to achieve the function. In the web project we need to use Socket to set up a listener. When the program starts, we need to start socket listener. Our application scenario is in the java project, which requires an external hardware device, such as a device, to communicate through tcp, obtain the data transmitted by the device, and respond to the data.
Take a look at the listening code of web:
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)
{
// New thread class
socketThread=new SocketThread(null);
// Starting a thread
socketThread.start();
}
}
}
Create thread:
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 create socket Service error ");
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()){
// Process the received data
Thread t = new Thread(new SocketOperate(socket));
t.start();
}else{
break;
}
}catch (Exception e) {
System.out.println("SocketThread create socket Service error ");
e.printStackTrace();
}
}
}
public void closeSocketServer(){
try {
if(null!=serverSocket && !serverSocket.isClosed())
{
serverSocket.close();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Processing received data:
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;
// What the thread handles Socket The corresponding input stream
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
{
// Use a continuous loop from Socket To read the data sent by the client
while (true)
{
content = readFromClient();
System.out.println(content);
if (content == null)
{
break;
}
OutputStream os = socket.getOutputStream();
os.write(("RES, OK,< As a , Xiao Ming >, ,#" + "\n").getBytes("utf-"));
os.flush();
}
}
catch (IOException e)
{
e.printStackTrace();
}
}
// Defines a way to read client data
private String readFromClient()
{
try
{
str = br.readLine();
return str;
}
// If an exception is caught, it should be Socket The corresponding client has been closed
catch (IOException e)
{
try {
br.close();
reader.close();
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return null;
}
}
Client code:
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++;
}
// Continue to cycle
os.close(); // Shut down Socket The output stream
is.close(); // Shut down Socket The input stream
socket.close(); // Shut down Socket
}
}
The above is the site to introduce you Java Web project using Socket communication multi-threaded, long connection method, I hope to help you!