如何找出Windows使用的是哪个Eclipse安装的JDK（不是JRE）

Question

How can I find out where the JDK which Eclipse is using to compile resides? It's possible to find the location(s) of JREs in Window, Preferences, Java. Even the compiler level (1.7) is there.

I can also find out which version of Java is installed using "where java", but "where javac" does not yield a result.

Since .java files can be compiled, some Java compiler (so a JDK) must be present. It's very tedious to search all directories and hasn't shown a usable result yet.

Somewhere in Eclipse's settings the path to the JDK must be saved. As far as I know, JAVA_HOME environment variable isn't used.

So how can I find out where the used JDK is? I actually need to find the programs xjc and schemagen, but the search of the total disk couldn't find it. I find this contradictory.

Answer 1

Help menu -> About -> Installation details button -> Configuration tab

Here you can find all system properties and Eclipse arguments including:

-vm
C:/Program Files (x86)/Java/jdk1.7.0_55/bin/javaw.exe

This is the Java VM on which Eclipse runs.

Eclipse has its internal compiler. It does not use javac to compile Java sources, Eclipse doesn't even require JDK just a JRE (and is still able to compile Java sources).

Answer 2

窗口->首选项-> Java->已安装的JRE- >如果还有更多的JRE ，则选择正确的JRE并检查JDK或JRE安装目录的位置