public class Demo1
{
    // instance variables - replace the example below with your own
    private Data1 d;
    private static int id;

    /**
     * Constructor for objects of class Demo
     */
    public Demo1(int id, Data1 d)
    {
        this.d=d;
        this.id=id;
    }

    public Data1 getData()
    {
        return d;
    }

    public void setData(Data1 d)
    {
        this.d=d;
    }

    public String toString()
    {
        String t;
        t = "";
        t="id: " + id + "\n"+d.toString();
        return t;
    }
}