深度复制

class DepthReading implements Cloneable{
	private double depth ;
	public DepthReading(double depth){
		this.depth = depth ;
	}
	public Object clone (){
		Object o = null ;
		try {
			 o = super.clone() ;
		} catch (CloneNotSupportedException e) {
			e.printStackTrace() ;
		}
		return o;
	}
}

class TempReading implements Cloneable{
	private long time ;
	private double temp ;
	public TempReading(double temp ){
		this.time= System.currentTimeMillis() ;
		this.temp = temp ;
	}
	
	public Object clone() {
		Object o= null ;
		try {
			o = super.clone();
		} catch (CloneNotSupportedException e) {
			e.printStackTrace();
		}
		return o;
	}
}

class OceanReading implements Cloneable {
	private DepthReading  depth ;
	private TempReading temp ;
	public OceanReading( double ddata, double tdata){
		temp = new TempReading(tdata) ;
		depth = new DepthReading(ddata) ;
	}
	
	public Object clone (){
		OceanReading  o = null ;
		try {
			 o = (OceanReading )super.clone() ;
		} catch (CloneNotSupportedException e) {
			e.printStackTrace() ;
		}
		//must clone handles 
		o.depth = (DepthReading)o.depth.clone() ;
		o.temp = (TempReading)o.temp.clone() ;
		return o;
	}
}

public class DeepCopy {
	
	public static void main (String [] args ){
		OceanReading reading = new OceanReading(33.9,100.5) ;
		//clone it 
		OceanReading r = (OceanReading) reading.clone() ;
	}
}