\documentclass[11pt,a4paper,onside]{article}
\usepackage[swedish]{babel} % svengelska
\usepackage[utf8]{inputenc} % utf8
\usepackage{listings}
\usepackage[usenames,dvipsnames]{color} % fördefinerade färger

\lstset{
language=Java,
captionpos=b,
tabsize=3,
frame=lines,
keywordstyle=\color{blue},
commentstyle=\color{OliveGreen},
stringstyle=\color{red},
numbers=left,
numberstyle=\tiny,
numbersep=5pt,
breaklines=true,
showstringspaces=false,
basicstyle=\footnotesize,
emph={label}
}

\author{Tethik} % whatever.

\begin{document}
    Test.
    \begin{lstlisting}
        // Kommentar HÄÄÄR
        int a, b, c;
        String test = "wat";
        for(;;)
        {
            if(null) break;
        }
        pie();
    \end{lstlisting}
\end{document}