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当创建给定的实例的过程很昂贵或非常复杂的时候，就使用原型模式来拷贝，这种方式在创建对象要耗费很多资源的时候效率提升显著。
实现深度克隆有两种方法，一种是实现Cloneable接口，重写clone()方法。另一种是通过序列化反序列化来获取对象的拷贝。
看一个介绍：http://blog.csdn.net/zhengzhb/article/details/7393528
看一个Demo:
public class Prototype implements Cloneable , Serializable{
String name;
Date date;
public Prototype(String name, Date date) {
this.name = name;
this.date = date;
}
public Prototype() {
}
public void setDate(Date date) {
this.date = date;
}public void setName(String name) {
this.name = name;
}
@Override
protected Object clone() throws CloneNotSupportedException {
return super.clone();
}
protected Object deepClone() throws CloneNotSupportedException {
Object obj = this.clone();
Prototype p = (Prototype) obj;
p.date = (Date) this.date.clone();
return obj;
}
}
public class ClientOne {
public static void shallowClone() throws Exception {
Date date = new Date(12356565656L);
Prototype p1 = new Prototype("原型对象", date);
Prototype p2 = (Prototype) p1.clone();
System.out.println(p1);
System.out.println(p1.date);
//p1.setDate(new Date(323232326565656L));
date.setTime(36565656562626L);
System.out.println(p2);
System.out.println(p2.date);
}
public static void deepClone() throws Exception {
Date date = new Date(12356565656L);
Prototype p1 = new Prototype("原型对象",date);
Prototype p2 = (Prototype) p1.deepClone();
System.out.println(p1);
System.out.println(p1.date);
date.setTime(36565656562626L);
System.out.println(p2);
System.out.println(p2.date);
}
public static void deepCloneSerialize() throws Exception {
Date date = new Date(12356565656L);
Prototype p1 = new Prototype("原型对象",date);
//通过序列化反序列化来新建一个对象
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(p1);
byte[] bytes = bos.toByteArray();
ByteArrayInputStream bis = new ByteArrayInputStream(bytes);
ObjectInputStream ois = new ObjectInputStream(bis);
Prototype p2 = (Prototype) ois.readObject();
System.out.println(p1);
System.out.println(p1.date);
date.setTime(36565656562626L);
System.out.println(p2);
System.out.println(p2.date);
}
public static void main(String[] args) throws Exception {
System.out.println("Shallow clone:");
shallowClone();
System.out.println("Deep clone:");
deepClone();
System.out.println("Deep clone serialize:");
deepCloneSerialize();
System.exit(0);
}
}
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原文地址：http://www.cnblogs.com/wxisme/p/4540634.html
