java - Running a jar file on other Windows versions

Question

I've written a code that is supposed to be exporting a set of windows registry keys. I've successfully written the code and was able to also send the results of executing the code as a jar file to my email. However, while testing the jar file ( I've included the piece of code in the build.xml from the java website that will allow me to run the jar file out of the dist folder) I was able to get the desired results on my machine because I wrote the code on a windows 8.1 machine. While testing it on another machine ( with Windows 8 and Windows 7 professional ) I was not able to execute the code and the error I was getting was as follows :

"Java Virtual Machine Launcher, A Java Exception has occurred."

I used to get that error message when I did not include the code in the build.xml page to allow the jar file to run out of the dist folder, but now I'm getting it when I'm executing the jar file on different machines other than my own

Running it from the command prompt this is what i got:

Exception in thread "main" java.lang.UnsupportedClassVersionError: smc_1/SMC_1
W1 : Unsupported major.minor version 52.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$100(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

Answer 1

@Sara, that error is a JVM mismatch error. I think you're trying to run a jar compiled for Java 8 on a system with Java 7 (or older) installed. Your options are (a) update the JVM to Java 8 or (b) recompile your application with the target set to 1.7 or whatever JVM you need to target, provided that your app doesn't include any Java 8-specific code. Oracle has some information on updating Java to the latest version here: http://www.java.com/en/download/help/java_update.xml