Java Networking
Sockets and URL Illustration . .
How to build client socket . .
Client Socket code example . .
Server Socket class . .
Building server socket code . .
Server Socket Code Example . .
URL classes . .
URL Code Example
What are sockets ?
Sockets are services at the end point of communication links.
We can exchange data between processes by transferring data through the socket.
Two types of sockets are implemented in Java:
STREAM SOCKETS
called TCP/IP sockets providing access to the Transport
Communication Protocol running over the Internet Protocol (TCP/IP).
TCP/IP sockets present major data communications on the Internet.
The basic features of TCP/IP sockets:
- They are connection oriented services transferring data
without record boundaries.
- The process will be informed when connection is broken.
Main Internet applications use TCP/IP services:
FTP - File Transfer Protocol
SMTP - Simple Mail Transfer Protocol
TELNET - the remote terminal connection
TCP/IP sockets implemented in Java with set of classes:
Socket, ServerSocket, SocketImpl and with
SocketImplFactory interface.
Stream sockets can be connected to Input/Output streams.
Once socket connection is established,
data can be transferred through these sockets as a byte stream.
DATAGRAM SOCKETS
called UDP sockets provide access to Unreliable Datagram
Protocol (UDP). UDP is a broadcast protocol, that does not guarantee
the reception of its messages.
- Datagram sockets are light weight sockets.
- They don't provide error checking, so they are faster than TCP/IP sockets.
In the case when you send the same information repeatedly you can
save resources by choosing UDP sockets.
UDP sockets implemented in Java with:
DatagramSocket and DatagramPacket classes.