#!/usr/bin/env perl

use strict;
use warnings;
use Inline Java => q(./Karl.java);
use feature qw(say);

say Karl->isaInt($_) for ( -10, 0, 10 );

__END__

karls-mac-mini:inline karl$ ./run.pl
-1
0
1

##</code><code>##

import java.lang.Integer;

class Karl {
    private Karl(){
    }
    public static int isaInt( int n){
        return Integer.signum(n);
    }
}