New Features and Enhancements 
 Guides
 For completeness, this section includes documentation related to 
    changes to the java.net package made previously in 
    the Java 1.1 platform: 
  - Networking Overview (also available 
    in PDF)
    Overview of networking facilities in java.net, including Addressing, 
    Making TCP Connections, Sending/Receiving Datagram Packets via UDP, Locating/Identifying 
    Network Resources, and Security.
     
  
 - URLConnection Caching API
  
  Detailed overview, with code samples, of the new cache management API.
  
  
 - Cookie Management
  
  Overview of how to deal with cookies, often used as an HTTP state management
  mechanism, in J2SE 5.0.
  
  
 - Persistent Connections
  
  Overview of the HTTP persistent connections (aka keep alive mechanisms), 
  and the means to control them.
  
  
 - Java Networking and Proxies
  
  In depth exploration, with code samples, of proxy management Java networking
  APIs including the newly introduced ProxySelector mechanism.
  
  
 - IPv6 Support (also available 
    in PDF)
    IPv6 support, including special IPv6 address types and dual-stack node.
     
  
 - Networking Properties 
    Descriptions of properties used by networking.
     
  
 - Orderly Versus Abortive Connection 
    Release in Java
    How to ensure orderly or graceful release of TCP connections in Networking 
    applications.
     
  
 - Extendable Socket and ServerSocket
    The design, rationale, and how to do it.
     
  
 - Socket Options
    Support for popular BSD-style options in the java base classes.
     
  
 - Socket Exceptions
    Subclasses of SocketException for finer granularity of handling network errors.
     
  
 - Miscellaneous
    Important bug fixes, new constructors, new methods, and more. 
 
 Networking API Reference