public static ArrayList<String> totaleProductenLijst = new ArrayList<String>();

System.out.println("===ArrayList===");
        System.out.println(totaleProductenLijst);

    //Create object
    Object[] obj=totaleProductenLijst.toArray();

    //convert object to string array
    String[] st=Arrays.copyOf(obj, obj.length, String[].class);

    System.out.println("Convert Array to Sring Array");

    //loop sysout
    System.out.println("====Menu====");

    for (int i = 0; i < st.length; i++) {
        System.out.println(st[i]);
    }

    Bon popup = new Bon(st);
    popup.setVisible(true);

public Bon(String[] st ) {
    initComponents();

    for (int i = 0; i < st.length; i++) {
        //listTotaalProducten.setListData(st[i]); (Gives Error)
        System.out.println(st[i]);
    }
}

===ArrayList===
[Hamburger, Hamburger, pizza]
Convert Array to Sring Array
====Menu====
Hamburger
Hamburger
pizza
====Bon====
Hamburger
Hamburger
pizza