title: Server & Client Connection in Java
body: <p>Here is an sample TCP/IP Server and Client programms</p>
  
  <p><strong>TCPServer</strong></p>
  
  <pre><code>import java.io.*;
  import java.net.*;
  
      class TCPServer
      {
         public static void main(String argv[]) throws Exception
            {
               String clientSentence;
               String capitalizedSentence;
               ServerSocket welcomeSocket = new ServerSocket(6789);
  
               while(true)
               {
                  Socket connectionSocket = welcomeSocket.accept();
                  BufferedReader inFromClient =
                     new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
                  DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
                  clientSentence = inFromClient.readLine();
                  System.out.println("Received: " + clientSentence);
                  capitalizedSentence = clientSentence.toUpperCase() + '\n';
                  outToClient.writeBytes(capitalizedSentence);
               }
            }
      } 
  </code></pre>
  
  <p><strong>TCPClient</strong></p>
  
  <pre><code>import java.io.*;
  import java.net.*;
  
  class TCPClient
  {
   public static void main(String argv[]) throws Exception
   {
    String sentence;
    String modifiedSentence;
    BufferedReader inFromUser = new BufferedReader( new InputStreamReader(System.in));
    Socket clientSocket = new Socket("localhost", 6789);
    DataOutputStream outToServer = new DataOutputStream(clientSocket.getOutputStream());
    BufferedReader inFromServer = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
    sentence = inFromUser.readLine();
    outToServer.writeBytes(sentence + '\n');
    modifiedSentence = inFromServer.readLine();
    System.out.println("FROM SERVER: " + modifiedSentence);
    clientSocket.close();
   }
  }
  </code></pre>
  
  <p>In that Client i need to send text hi to Server. Onces the server reads that text Hi from Client side it display Client Id with Text is Active now </p>