Points while writing client Representational State Transfer (REST) ful web services

This blog confines only to consume RESTful web service and not writing web service itself .
Points -

• Basic framework available - Outh(only for web service authentication ) , Apache CXF  etc.
• Sample Google API client using CXF , and Jasckson Json processor.
• General HTTP exceptions to handle 
• Retry Logic in case of failure