Control panel has it's own part for java. Depending on if java is included in path, you can also try it on command prompt or through windows explorer
java sits in program files(x86) if 32 bit and in program files if 64 bit. path name usually tells the java version too.
following would work if your java version was 64 bit and 1.8.051 which it most likely is not, Java tends to update quite often.
"C:\Program Files\Java\jre1.8.0_51\bin\java.exe" -version
for latest version, it would be: and yes, since path contains spaces, "'s are necessary
"C:\Program Files\Java\jre1.8.0_60\bin\java.exe" -version
however to clarify another possibility, the java command might have something typed wrong:
Unrecognized option: --version
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.
in that, I first tried --version instead of -version and.. fail. so if your original launching command has a typo, error message should reflect it
in any case, java can be downloaded from:
http://www.oracle.com/technetwork/java/javase/downloads/jre8-downloads-2133155.html
I would choose the 2nd from bottom x64 version.