title: How set environment variables in eclipse
body: <p>How set  <code>ECLIPSE_HOME</code> variable .  and by default how it set by eclipse..?<br>
  ...there is many variables <code>JRE_LIB,JRE_EXT,JUNIT_HOME</code>... and many more..<br>
  How these are set by eclipse and if some one wants to change it then what should he do..??</p>