Ubuntu launch Eclipse error: A java RunTime Environment (JRE) or Java development Kit (JDK) must

Originally thought to be the JDK environment variable configuration error, so from the Internet to find a variety of configuration environment variable method, but also pay attention to the problem of space, can no matter how to change, or this error! Later on the Internet to see a strange way, I do not know why this is OK?

Method: Enter your Eclipse directory, open with terminal, switch to root, and enter:
mkdir JRE
CD JRE
Ln-s your JDK directory/bin bin

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Ubuntu launch Eclipse error: A java RunTime Environment (JRE) or Java development Kit (JDK) must