Book Image

Learning Network Programming with Java

Book Image

Learning Network Programming with Java

Overview of this book

Network-aware applications are becoming more prevalent and play an ever-increasing role in the world today. Connecting and using an Internet-based service is a frequent requirement for many applications. Java provides numerous classes that have evolved over the years to meet evolving network needs. These range from low-level socket and IP-based approaches to those encapsulated in software services. This book explores how Java supports networks, starting with the basics and then advancing to more complex topics. An overview of each relevant network technology is presented followed by detailed examples of how to use Java to support these technologies. We start with the basics of networking and then explore how Java supports the development of client/server and peer-to-peer applications. The NIO packages are examined as well as multitasking and how network applications can address practical issues such as security. A discussion on networking concepts will put many network issues into perspective and let you focus on the appropriate technology for the problem at hand. The examples used will provide a good starting point to develop similar capabilities for many of your network needs
Table of Contents (16 chapters)
Learning Network Programming with Java
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

The nature of HTTP messages


Let's examine the format of an HTTP message. Messages are either a request message sent from a client to a server, or a response message sent from a server to a client. Based on an understanding of the format, we will show you how Java supports these messages. HTTP messages are, for the most part, readable by humans. Both the request and response messages use this structure:

  • A line indicating the type of message

  • Zero or more header lines

  • A blank line

  • An optional message body containing data

The following is an example of an HTTP request:

GET /index HTTP/1.0

User-Agent: Mozilla/5.0

A client request message consists of an initial request line and zero or more header lines. A response message consists of an initial response line (called the status line), zero or more header lines, and an optional message body.

Let's examine these elements in more detail.

Initial request line format

The formats of the request and response initial lines differ. The request line consists of...