This document provides an overview of socket programming. It discusses server-client communication where the server listens on a specific port for connection requests from clients. The Java .net package contains Socket and ServerSocket classes that implement the client and server sides of the connection. The Socket class is used by clients to connect to servers, while the ServerSocket class is used by servers to listen for incoming connections from clients. Key methods for each class are also outlined.

1. Presentation On Socket Programming
LAN BASED
Mini Project

2. Contents
 Socket Programming
 Server-Client Communication
 .net Package
 The InetAddress Class & its methods
 getLocalHost()
 getByName(String hostName)
 getAllByName(String hostName)
 getAddress() & getHostName()
 Socket Class
 ServerSocketClass

3. Socket Programming
Networking - process of making two or more computers communicate.
The important concept associated with networking is the concept of
Sockets and Ports.
SOCKET - A socket is one end-point of a two-way communication link
between two programs running on the network.
Socket classes are used to represent the connection between a client
program and a server program.

4. Server-Client
Communication
 Normally, a server has a socket that is bound to a specific port
number.
 On the client-side: The client knows the hostname of the machine on
which the server is running and the port number on which the server
is listening.
 To make a connection request, the client tries to connect with the
server on the server's machine and port.
 If everything goes well, the server accepts the connection.
 On the client side, if the connection is accepted, a socket is
successfully created and the client can use the socket to
communicate with the server.

5. .net Package
 Provide support for networking.
 Contains classes and interfaces to encapsulate the
“Socket” Paradigm.
 The java.net package provides two classes—
 Socket - implement the client side of the connection
 ServerSocket- implement the server side of the connection

6. Socket Class
 The Socket class ,basically used to create client sockets, is
designed to connect to server socket and initiate protocol
exchanges.
 When Socket object is created, it implicitly establishes the
connection b/w client and server.
 Socket defines the constructors to create client sockets.
Constructors:-
Socket(String hostname, int port);
Socket(InetAdrress ipaddr, int port);

7. ServerSocket Class
The ServerSocket class, basically used to create server sockets, is
designed to be a listener, which waits for client to connect before
doing anything.
Constructors:-
ServerSocket ( int port );
ServerSocket ( int port, int queueLength);
Method:-
Socket accept();
accept() is a blocking call that waits for a client to initiate
communication and returns a normal Socket, that is used for
communication with the client.