Connection oriented socket programming in java

Write a connection oriented socket program which can exchange the message between server and client once the connection is established.

Java Sockets makes networked programming easy. the java.net package offers developers a wide range of tools to create networked applications. the socket class provides the access to a TCP connection between hosts. Unfortunately, it doesn't provide an API for detecting a dropped connection from the remote system.

Java sockets can facilitate both TCP and UDP type protocols. While UDP connections are non-persistent, TCP connections often support a dynamic back-and-forth exchange of information between two network end systems.

Example of Java Socket Programming (Read and Write from both client and server)

//save this code in file name MyOwnServer.java

1. import java.net.*;  
2. import java.io.*;  
3. class MyFirstServer{  
4. public static void main(String[] args)throws Exception{  
5. ServerSocket servSocket=new ServerSocket(3333);  
6. Socket sock=servSocket.accept();  
7. DataInputStream dataInput=new DataInputStream(sock.getInputStream());  
8. DataOutputStream dataOutput=new DataOutputStream(spck.getOutputStream());  
9. BufferedReader buffers=new BufferedReader(new InputStreamReader(System.in));  
10.   
11. String string1="";
12. String string2="";  
13. while(!string1.equals("stop")){  
14. string1=dataInput.readUTF();  
15. System.out.println("client says: "+string1);  
16. string2=buffers.readLine();  
17. dataOutput.writeUTF(string2);  
18. dataOutput.flush();  
19. }  
20. dataInput.close();  
21. sock.close();  
22. servSocket.close();  
23. }
24. }

//save this code in file name MyOwnClient.java

1. import java.net.*;  
2. import java.io.*;  
3. class MyFirstClient{  
4. public static void main(String[] args)throws Exception{  
5. Socket sock=new Socket("localhost",3333);  
6. DataInputStream dataInput=new DataInputStream(sock.getInputStream());  
7. DataOutputStream dataOutput=new DataOutputStream(spck.getOutputStream());  
8. BufferedReader buffers=new BufferedReader(new InputStreamReader(System.in));  
9.   
10. String string1="";
11. String string2="";  
12. while(!string1.equals("stop")){  
13. string1=buffers.readLine(); 
14. dataOutput.writeUTF(string1);  
15. dataOutput.flush();  
16. string2=dataInput.readUTF();
17. System.out.println("server says:",string2);
18. }  
19. dataOutput.close();  
20. sock.close();  
21. }
22. }

To run the above given program you must open two command prompts and run each program at each command prompt.

After running the program first the client will write the message to the server then server will receive and display the message written by client. then Server will write the message to the client and client will receive and display the message sent by server. Then this process will go on.