Multithreaded TCP server:
import java.io.*;
import java.net.*;
import java.util.*;
public class MultiServe implements Runnable
{
private ServerSocket ss;
public static void main(String args[]) throws Exception
{
MultiServe m = new MultiServe();
m.go();
}
public void go() throws Exception
{
ss = new ServerSocket(DayClient1.DAYTIME_PORT, 5);
Thread t1 = new Thread(this, "1");
Thread t2 = new Thread(this, "2");
Thread t3 = new Thread(this, "3");
t1.start(); t2.start(); t3.start();
}
public void run()
{
Socket s = null;
BufferedWriter out = null;
String myname = Thread.currentThread().getName();
for (;;)
{
try
{
System.out.println("thread " + myname + " about to accept..");
s = ss.accept();
System.out.println("thread " + myname + " accepted a connection");
out = new BufferedWriter(
new OutputStreamWriter(s.getOutputStream()));
out.write(myname + " " + new Date());
Thread.sleep(10000);
out.write("\n");
out.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
}
Client:
//A TCP Client for the Daytime service
import java.net.*;
import java.io.*;
public class DayClient1 {
public static final int DAYTIME_PORT = 2012;
String host;
Socket s;
public static void main(String args[]) throws
IOException {
DayClient1 that = new DayClient1("192.681.158.1");
that.go();
}
public DayClient1(String host) {
this.host = host;
}
public void go() throws IOException {
s = new Socket(host, DAYTIME_PORT);
BufferedReader i = new BufferedReader(
new InputStreamReader(s.getInputStream()));
System.out.println(i.readLine());
i.close();
s.close();
}
}
Output:
‘OR’
Server:
import java.io.*;
import java.net.*;
public final class TcpServerStarter
{
public static void main(String[] args) throws IOException
{
ServerSocket serverSocket = null;
boolean listening = true;
try
{
serverSocket = new ServerSocket(2012);
}
catch (IOException e)
{
System.err.println("Could not listen on port: 2012.");
System.exit(-1);
}
while (listening)
new ConnectionHandler( serverSocket.accept()).start();
serverSocket.close();
}
}
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.Date;
public final class ConnectionHandler extends Thread {
private Socket socket;
public ConnectionHandler(Socket socket){
setName("ConnectionHandler");
this.socket = socket;
}
public void run(){
BufferedReader in = null;
PrintWriter out = null;
String request;
try{
// Get the input and output streams
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out = new PrintWriter(socket.getOutputStream(), true);
while( (request = in.readLine()) != null){
// Deliver the current date and time if the client sends GET_TIME
if(request.equals("GET_TIME"))
out.println(new Date().toString());
// Deliver the JRE version if the client sends GET_JAVA_VERSION
else if(request.equals("GET_JAVA_VERSION"))
out.println(System.getProperty("java.version"));
// Exit the loop if the client sends CLOSE
else if(request.equals("CLOSE"))
break;
}
}
catch(IOException e){
e.printStackTrace();
}
finally{
try{
if(socket != null)
socket.close(); // Close the socket (closing the socket also closes the input and output streams)
}
catch(IOException e){
e.printStackTrace();
}
}
}
}
Client:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
public final class TcpClient {
private void process() {
Socket socket = null;
BufferedReader in = null;
PrintWriter out = null;
try{
/* Establish a TCP connection with the server running locally on the port number 2012.
* You can write "localhost" instead of "192.681.158.1".
*/
socket = new Socket("192.681.158.1", 2012);
// Get the input and output streams
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out = new PrintWriter(socket.getOutputStream(), true);
// Send a GET_TIME request and print the response to the standard output
out.println("GET_TIME");
System.out.println(in.readLine());
// Send a GET_JAVA_VERSION request and print the response to the standard output
out.println("GET_JAVA_VERSION");
System.out.println(in.readLine());
// Send a CLOSE request to the server to end communication
out.println("CLOSE");
}
catch(IOException e){
e.printStackTrace();
}
finally{
try{
if(socket != null)
socket.close(); // Close the socket (closing the socket also closes the input and output streams)
}
catch(IOException e){
e.printStackTrace();
}
}
}
public static void main(String[] args){
new TcpClient().process();
}
}
Output:
