package interfaces;

public class TestClone
{
    public static void main(String[] args) throws Exception 
    {
        try
        {
            House house1 = new House(1,1234);
            House house2 = house1;
            House house3 = (House)house1.clone();
            System.out.println(house1 == house2);
            System.out.println(house1.compareTo(house2));        //campareTo not comparaTo
            System.out.println(house1 == house3);
            System.out.println(house1.compareTo(house3));        //campareTo not comparaTo
        }
        catch(CloneNotSupportedException e)                //捕获异常.
        {
            e.printStackTrace();
        }
    }
}

class House implements Cloneable, Comparable 
{
    private int id;
    private double area;
    private java.util.Date whenBuilt;
    public House(int id,double area)
    {
        this.id = id;
        this.area = area;
        whenBuilt = new java.util.Date();
    }

    public int getId()
    {
        return id;
    }

    public double getArea()
    {
        return area;
    }

    public java.util.Date getWhenBuilt()
    {
        return whenBuilt;
    }

    public Object clone() throws CloneNotSupportedException
    {
        return super.clone();
    }

    public int compareTo(Object o)                        //campareTo not comparaTo
    {
        if(area > ((House)o).area)
        return 1;
        else if (area <((House)o).area)
        return -1;
        else return 0;
    }
}

------解决方案--------------------
 public static void main(String[] args) throws Exception ,这句不要抛出就可。