How do you fix UnsupportedClassVersionError

Question

I have created an application that will run on any computer with the JDK. I want to make it an executable file so that you don't have to have the JDK to run it. I downloaded a Native compiler that will compile your Java application into an executable. It asks you for two things: The directory with all your application's .java and .class files. It asks you to specify a main .class file. It comes with a few sample applications that you can compile. I am using the most simple one the hello world application. Here is the hello.java file
public class hello
static public void main(String args[])
System.out.println("Hello, World!");
Now, this file came in a directory with the files hello.class and hello.java. If I use the native compiler (Excelsior JET is it's name) and i specify the directory that contains the hello.class and hello.java file as the application's working directory, and Hello.class as the main class and then click test, the native compiler will run the hello world application just fine. After testing I can click compile and it will turn that application and to a hello.exe file that will run on any windows computer without a JDK. Now, if specify the information for my own Java application, (which would be it's working directory C:\Vocab\) and Vocab.class as the main class, the native compiler will not be able to test and certainly not compile it and it and will give me this output:
The application has started with command line:
java -cp C:\Vocab Vocab
Exception in thread "main" java.lang.UnsupportedClassVersionError
at java.lang.Void.<unknown>(Unknown Source)
at java.lang.Void.<unknown>(Unknown Source)
at java.lang.Void.<unknown>(Unknown Source)
at java.lang.Void.<unknown>(Unknown Source)
The application has terminated with exit code: 1
You see the part that says java -cp C:\Vocab Vocab? If I type that into the command prompt, my application will run. So why wont it run here? I think the answer lies here:
Before you begin
Before using Excelsior JET to compile your Java application, make sure that the application runs properly on the reference implementation of the Java platform, such as Sun JRE 5.0.
Ok that is in the help section that comes with Excelsior JET, the main compiler. Now back to that hello world application. As i mentioned before it comes with the hello.java and hello.class file. I can take that hello.java file and use either jGrasp, Netbeans, or go to the directory
C:\Program Files\Java\jdk1.6.0\bin and use the javac.exe file to generate a hello.class file. Now if I take that hello.class file that was generated from the hello.java file that was in the hello world directory, and overwrite the hello.class file that came with the native compiler, I can try testing the compiler but i just get the same error that i get when trying to test/compile my own application. Let me clarify:
hello.class that came with the compiler will test and compile
hello.class that i made with jGrasp, Netbeans, or Javac will not test or compile.
So what do I use to create the proper .class files that will test/compile?

Answer 1

That means the box is having trouble communicating to the VOD servers. Please reseat the coax cord from both ends (the wall end and the box end). Once the coax cord is back on, reboot the box by unplugging power cord for 20 seconds then plugging back in. If you continue having problems with the VOD connectivity, please send me a private message so I can get your info directly.
Anthony_VZ
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