ADT Plugin in Eclipse not shown

I just installed the Android Developer Tools for Eclipse and restarted the programm. After that I am supposed to configure the plugin under Window > Preferences > Android, but there are NO signs of any Android Plugin anywhe开发者_StackOverflow中文版re. The Plugin is just invisible, altough it is marked as installed.

I installed the ADT-Plugin on two other computers some time before. Never encountered that problem.

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You need to upgrade the Java setup on your machine. That was the problem. I wasted some half a day.