原型模式--深复制/浅复制
原型模式用于克隆复杂对象,由于new一个实例对象会消耗大部分时间,所以原型模式可以节约大量时间
1 public class Sheep implements Cloneable{ 2 private String name; 3 private Date birth; 4 public Sheep(String name, Date birth) { 5 this.name = name; 6 this.birth = birth; 7 } 8 @Override 9 protected Object clone(){ 10 Sheep obj = null; 11 try { 12 obj = (Sheep) super.clone(); 13 //深复制 14 // obj.birth = (Date) this.birth.clone(); 15 } catch (CloneNotSupportedException e) { 16 e.printStackTrace(); 17 } 18 return obj; 19 } 20 public String getName() { 21 return name; 22 } 23 public void setName(String name) { 24 this.name = name; 25 } 26 public Date getBirth() { 27 return birth; 28 } 29 public void setBirth(Date birth) { 30 this.birth = birth; 31 } 32 33 }
import java.util.Date; public class Client { public static void main(String[] args) { Date date = new Date(1515529952L); Sheep s1 = new Sheep("s1",date); Sheep s2 = (Sheep) s1.clone(); System.out.println(s1.getBirth()); System.out.println(s2.getBirth()); date.setTime(15L);//修改后 System.out.println(s1.getBirth()); System.out.println(s2.getBirth()); } }
1 浅复制 2 Sun Jan 18 20:58:49 CST 1970 3 Sun Jan 18 20:58:49 CST 1970 4 //修改后 5 Thu Jan 01 08:00:00 CST 1970 6 Thu Jan 01 08:00:00 CST 1970 7 深复制 8 Sun Jan 18 20:58:49 CST 1970 9 Sun Jan 18 20:58:49 CST 1970 10 修改后 11 Thu Jan 01 08:00:00 CST 1970 //只对s1修改 12 Sun Jan 18 20:58:49 CST 1970