What are the requirements for use of gdata java library in contact API?

I am newbie with google authentication.

I want to know that for develop small api that add,delete and display gmail contact with use of java. I had download java library for that but not perfect idea how to use 开发者_JS百科it with eclipse and what are the pre requirenment in my system for use this library.

I have JDK 1.6.. eclipse

does i need to install apache tomcat,apache ant,sun java's mailse api

because when i search for use of gdata java library i got this http://code.google.com/apis/gdata/articles/java_client_lib.html#windows

please give simple way to use gdata java library if any one have.