#2 Decompiling but no contents!

[Anonymous]

After succesfully installing the program, I just get
the following , when I try to decompile a class:
-----------------------------------
// Decompiled by JReversePro 1.4.1
// Home : http://jrevpro.sourceforge.net
// JVM VERSiON: 46.0
// SOURCEFILE: ArithmeticDemo.java

import java.io.PrintStream;

public class ArithmeticDemo{

public ArithmeticDemo()
{
}

public static void main(String[] stringArr)
{
}

}
---------------------------------------

What have I done wrong?