The Commons HttpClient project is now end of life, and is no longer being developed. It has been replaced by the Apache HttpComponents project in its HttpClient and HttpCore modules, which offer better performance and more flexibility.
The Hyper-Text Transfer Protocol (HTTP) is perhaps the most significant protocol used on the Internet today. Web services, network-enabled appliances and the growth of network computing continue to expand the role of the HTTP protocol beyond user-driven web browsers, while increasing the number of applications that require HTTP support.
Although the java.net package provides basic functionality for accessing resources via HTTP, it doesn't provide the full flexibility or functionality needed by many applications. The Jakarta Commons HttpClient component seeks to fill this void by providing an efficient, up-to-date, and feature-rich package implementing the client side of the most recent HTTP standards and recommendations. See the Features page for more details on standards compliance and capabilities.
Designed for extension while providing robust support for the base HTTP protocol, the HttpClient component may be of interest to anyone building HTTP-aware client applications such as web browsers, web service clients, or systems that leverage or extend the HTTP protocol for distributed communication.
There are many projects that use HttpClient to provide the core HTTP functionality. Some of these are open source with project pages you can find on the web while others are closed source that you would never see or hear about. The Apache Source License provides maximum flexibility for source and binary reuse. Please see the Applications page for projects using HttpClient.
HttpClient was started in 2001 as a subproject of the Jakarta Commons, based on code developed by the Jakarta Slide project. It was promoted out of the Commons in 2004, graduating to a separate Jakarta project. In 2005, the HttpComponents project at Jakarta was created, with the task of developing a successor to HttpClient 3.x and to maintain the existing codebase until the new one is ready to take over. The Commons project, cradle of HttpClient, left Jakarta in 2007 to become an independent Top Level Project. Later in the same year, the HttpComponents project also left Jakarta to become an independent Top Level Project, taking the responsibility for maintaining HttpClient with it.