How to open/run .jar file (double-click not working)?

Question

I can't open or run my .jar file.

I just installed java, but I tried to open the .jar with other programs first, so the double-click defaults to something else and I can't change it back.

java -jar myfile.jar`

Above command returns:

'java' is not recognized as an internal or external command, operable program or batch file.

Is there a way I can still open/run this?

e: OS is Windows 8.

Also, I downloaded the .jar file; didn't create it myself (if that's relevant) Not sure if it contains an executable (but I think it does).

Answer 1

you can use the command prompt:

javaw.exe -jar yourfile.jar

Hope it works for you.

Answer 2

There are two different types of Java to download: The JDK, which is used to write Java programs, and the RE (runtime environment), which is used to actually run Java programs. Are you sure that you installed the RE instead of the SDK?