Selenium Web driver is basically supported various languages and this is the main advantage of the Selenium. but limitation with that this is applicable only for the web based application not for the windows.
Language Supported by the Selenium are:
Jave
C#
PHP
PERL
PYTHON
RUBY
Most demanding combination is Selenium with Java
Download the Selenium Webdriver from the given Location:
http://docs.seleniumhq.org/download/
Please click on the Download Link against the JAVA.
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After download of the same , a folder has been created as mention below :
Name that folder as "selenium-java-216.1"
Open it and there a folder named as lib--These are the files which we have to map with Eclipse