I have a Constants class and a Variable class.

I need to initialize a constant in the Constants class:
public static final String FILE_NAME;

The Variable class has a public String method that returns the full
pathway for the file name.
public String getVariable( String variableName ) throws Exception;

I have a getPath() method in Constants that calls getVariable in
Variable:
private static String getPath( String variableName ) throws Exception {
        try    {
            Variable v = new Variable();
            return v.getVariable( variableName );
        }
        catch ( Exception e )
        {
            throw e;
        }
}

Now to initialize Constants.FILE_NAME, I need to call getPath() to pick
up the pathway.
If I do:

public static final String FILE_NAME = Constants.getPath( "PATH_NAME"
);

I got an "unhandled exception error".

If I wrap "public static final String FILE_NAME = Constants.getPath(
"PATH_NAME" );"
with a try-catch block as follows:

    try     {
    public static final String FILENAME = Constants.getPath("PATH_NAME");
    }
    catch (Exception e){
        throw e;
    }
I got:
Syntax error, insert } to complete block
Syntax error on tokens, constructor ConstructorHeaderName expected
instead.

How do I go about initializing the value of FILE_NAME?  I *must* use
Variable::getVariable().
Thanks for your help.