Weird issue with environment variables

Question

I have this strange Issue with environment variables on my windows 7 system. Its been there for an year and I have had a work around but I need to solve it now:

I have an environment variable JAVA_HOME set as C:\\Program Files\\Java\\jdk1.6.0_39\\ . And in my PATH I have added %JAVA_HOME%\\bin; .

But when I do java -version it prints "1.7.0_11" and when I do javac -version it prints as expected 1.6.0_39

I do not know why 1.7.0_11 is printed for java -version . I have checked my PATH and have added JAVA_HOME only once. How can I know which env variable is responsible for using my java.exe ? How do I avoid it?

Answer 1

几乎可以肯定，它是c:\\Windows\\System32中java.exe的版本，它的路径可能要比引用JAVA_HOME的部分早。

Answer 2

Ok, hopefully %JAVA_HOME\\bin%; is a typo, but if not, it should be %JAVA_HOME%\\bin .

For the rest - java -version is looking for your JRE, not your JDK. javac is looking for the JDK.

Check to see if you have a JRE-related environment variable. As well, check your path for any hard references to the Java 7 JRE. Finally, look in C:\\Windows\\System32 and see if there is a java.exe there.

Answer 3

Java.exe is installed on windows twice. The first location is where you expect it: under your JAVA_HOME . The second one is under c:/windows . Since this path always wins any other user defined path you are running java from here. If you want to hold several java environments and switch between them by changing your JAVA_HOME just remove java.exe from c:/windows .