I fixed the issue;
with some work around it was throwing
An error occurred while installing the items
session context was
profile=PlatformProfile, phase=org.eclipse.equinox.internal.provisional.p2. engine.phases.Install, operand=null --> [R]org.eclipse.cvs 1.0.400.v201002111343, action=org.eclipse.equinox.internal.p2.touchpoint. eclipse.actions.InstallBundleAction).
Cannot connect to keystore.
This trust engine is read only.
The artifact file for osgi.bundle,org.eclipse.cvs,1.0.400.v201002111343 was not found
Solution:
1) It looks the permission issue;
2) I uninstalled my eclipse
3) Installed eclipse from eclipse-jee-galileo-SR2-linux-gtk.tar.gz in my home folder (/home/krishnan)
4) change the owner of the .gz file in case the owner is root (sudo chown krishnan eclipse-jee-galileo-SR2-linux-gtk.tar.gz)
5) It created a folder /home/krishnan/eclipse
6) Now star the eclipse from the home folder ( double click the file named eclipse)
7) You r all set to install the ADT
-Krishnan