Android/Java Javadoc missing after updating Android SDK

Deleting .metadata is not a good solution because you'll lose all of your settings. I poked at this a bit and was able to figure it out. Full writeup is here:

http://hacksoflife.blogspot.com/2011/02/losing-javadocs-in-eclipse-solution.html

1) In eclipse, right click on your Android project and select Properties2) On the menu on the left, select "Java Build Path"3) On the right hand side, select the "tab" labelled "Libraries".4) Here you should see the Android SDK that you're targeting. For example: "Android 2.2".5) Click on the arrow to the left of the Android SDK to expand the sublevels.6) Find "Android.jar" and click on the arrow to the left of that one as well to expand it.7) You'll see a setting called "Javadoc location". Select that and then click on the     "Edit" button.8) At the top, RESELECT the path to your javadocs. This is usually "path_to_android_sdk/android-sdk-mac_86/docs/reference/". I say RESELECT because even if it's right, you should browse and do it over anyway.9) Click on "validate". You should be all set now!

I figured out how to fix this problem. All i had to do was delete the .metadata folder in my workspace, and restart eclipse. note: this will clear all your eclipse preferences, settings, etc. your workspace projects will need to be added again.

also consider the following link as it seems to be very helpful for most people viewing this: http://hacksoflife.blogspot.com/2011/02/losing-javadocs-in-eclipse-solution.html