Snowguy13, instantiating a class uses memory. Granted, most machines have more than enough, but it is still a good practice to not use more than you need. That said, if you are using a class just for reference or computing type functions then you do not need to instantiate a class just to use a function within that class.
Therefore, you would find more use in using the following statements:
For class declaration:
public final class Converter (this will define the class and non-instantiating)
public static String toHex(long helper){
**use the same code you have here except omit references to baseTenPower since helper is loaded directly**}
Note, also, that it would, probably be wise to overload the method to allow for use of int, byte, etc to be sent (as well as an empty argument)
Using this setup, you call the method from within your program and send its argument directly.
As an example, using your existing test code:
JOptionPane.showMessageDialog(
null,
"Your number, " + number + ", in hexadecimal format is " + toHexadecimal(number) + ".",
"Result",
JOptionPane.INFORMATION_MESSAGE);
For reference to this type of setup, see the api for the java.lang.Math class. If you use Netbeans, add this line of code to your class (double x = pow(12,2);), then right-click on it and select "Show Source" which will open the entire class source code and you can see the Sun code.
Don't know if all this helps or makes it worse for you, but, figured I'd throw it in.
Good Luck. :)