Android programming is not working in eclipse
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My Eclipse was working fine until i updated my sdk.Then suddently everything started to show little weirder.Actyually I was working in Ubuntu 12.04 ,Which stopped showing even Java projects after updation.When I click New-->Project  I can't find neither java/Android.I cant even find XML.I have done so many methods listed in some sites.But nothing is working for me.Can anyone please suggest a solution.
I have even tried in windows.But same problem happened & it says " Android Development Tools (20.0.0.v201206242043-391819) requires plug-in "org.eclipse.core.runtime (3.6.0)", or later version."
what to do?
please give me a solution

Thanking you in advance