What is the task of Socket class? Write program using socket program to send the string "hello" to the client.

 The Socket class in Java provides a way to create client-side sockets that can connect to a server on a given IP address and port number. Once the connection is established, the client and server can exchange data through the socket.

Here's an example Java program that creates a server socket and sends the string "hello" to the client:

import java.net.*;
import java.io.*;

public class Server {
    public static void main(String[] args) {
        try {
            // create a server socket object
            ServerSocket serverSocket = new ServerSocket(8080);
            
            // wait for a client to connect
            Socket clientSocket = serverSocket.accept();
            
            // create an output stream to send data to the client
            OutputStream os = clientSocket.getOutputStream();
            PrintWriter writer = new PrintWriter(os, true);
            
            // send the string "hello" to the client
            writer.println("hello");
            
            // close the output stream, socket, and server socket
            writer.close();
            os.close();
            clientSocket.close();
            serverSocket.close();
        } catch (Exception e) {
            System.out.println("Exception: " + e.getMessage());
        }
    }
}

This program creates a ServerSocket object on port 8080 and waits for a client to connect. Once a client connects, it creates an output stream to send data to the client and sends the string "hello" using a PrintWriter. Finally, it closes the output stream, client socket, and server socket.

Note that in order to run this program, there must be a client running that is able to receive and process the data sent by the server.