How do I find where JDK is installed on my windows machine?

I need to know where JDK is located on my machine.

On running Java -version in cmd, it shows the version as '1.6.xx'. To find the location of this SDK on my machine I tried using echo %JAVA_HOME% but it is only showing 'JAVA_HOME' (as there is no 'JAVA_PATH' var set in my environment variables).

If you are using Linux/Unix/Mac OS X:

Try this:

$ which java

Should output the exact location.

After that, you can set JAVA_HOME environment variable yourself.

In my computer (Mac OS X - Snow Leopard):

$ which java
/usr/bin/java
$ ls -l /usr/bin/java
lrwxr-xr-x  1 root  wheel  74 Nov  7 07:59 /usr/bin/java -> /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/java

If you are using Windows:

c:\> for %i in (java.exe) do @echo.   %~$PATH:i

Windows > Start > cmd >

C:> for %i in (javac.exe) do @echo.   %~$PATH:i

If you have a JDK installed, the Path is displayed,
for example: C:\Program Files\Java\jdk1.6.0_30\bin\javac.exe