原型模式核心复制，每次new出来的对象完全不一样，实现对象之间的隔离。 学习前最好先掌握jAVA值传递和深浅拷贝
设计模式，一定要敲代码理解

浅拷贝

克隆出对象，其中两者的引用类型属性是同一个对象。

对象信息

/*** @author ggbond* @date 2024年04月03日 08:38*/
public class Mankind01 implements Cloneable {private  int age;private Date birth;public Mankind01(int age, Date birth){this.age=age;this.birth=birth;}public int getAge() {return age;}public Date getBirth() {return birth;}public void setAge(int age) {this.age = age;}public void setBirth(Date birth) {this.birth = birth;}@Overrideprotected Mankind01 clone() throws CloneNotSupportedException {return (Mankind01) super.clone();}
}

测试

/*** @author ggbond* @date 2024年04月03日 08:42**/
public class test01 {public static void main(String[] args) throws Exception {Date birth=new Date(2022,4,3);int age=25;Mankind01 m1=new Mankind01(age,birth);Mankind01 m2=m1.clone();System.out.println("m1.age:"+m1.getAge()+"  "+"m2.age:"+m2.getAge());System.out.println("m1.birth:"+m1.getBirth()+"  "+"m2.birth:"+m2.getBirth());System.out.println("-----------");age=21; birth.setTime(1232321321L);System.out.println(m1.getBirth() == m2.getBirth()); // trueSystem.out.println("m1.age:"+m1.getAge()+"  "+"m2.age:"+m2.getAge());System.out.println("m1.birth:"+m1.getBirth()+"  "+"m2.birth:"+m2.getBirth());}
}

测试结果发现， m1,m2 中的属性 引用类型 Date birth 是指向同一个对象

m1.age:25  m2.age:25
m1.birth:Wed May 03 00:00:00 CST 3922  m2.birth:Wed May 03 00:00:00 CST 3922
-----------
true
m1.age:25  m2.age:25
m1.birth:Thu Jan 15 14:18:41 CST 1970  m2.birth:Thu Jan 15 14:18:41 CST 1970

深拷贝

对象信息

/*** @author ggbond* @date 2024年04月03日 08:38*/
public class Mankind02 implements Cloneable {private  int age;private Date birth;public Mankind02(int age, Date birth){this.age=age;this.birth=birth;}public int getAge() {return age;}public Date getBirth() {return birth;}public void setAge(int age) {this.age = age;}public void setBirth(Date birth) {this.birth = birth;}@Overrideprotected Mankind02 clone() throws CloneNotSupportedException {Mankind02 m = (Mankind02) super.clone();m.setBirth((Date) birth.clone());return m;}
}

测试

/*** @author ggbond* @date 2024年04月03日 08:42* 原型模式，本质是克隆复制对象。*/
public class test02 {public static void main(String[] args) throws Exception {Date birth=new Date(2022,4,3);int age=25;Mankind02 m1=new Mankind02(age,birth);Mankind02 m2=m1.clone();System.out.println("m1.age:"+m1.getAge()+"  "+"m2.age:"+m2.getAge());System.out.println("m1.birth:"+m1.getBirth()+"  "+"m2.birth:"+m2.getBirth());System.out.println("-----------");age=21; birth.setTime(123232321L);System.out.println(m1.getBirth() == m2.getBirth()); // trueSystem.out.println("m1.age:"+m1.getAge()+"  "+"m2.age:"+m2.getAge());System.out.println("m1.birth:"+m1.getBirth()+"  "+"m2.birth:"+m2.getBirth());}
}

结果

m1.age:25  m2.age:25
m1.birth:Wed May 03 00:00:00 CST 3922  m2.birth:Wed May 03 00:00:00 CST 3922
-----------
false
m1.age:25  m2.age:25
m1.birth:Fri Jan 02 18:13:52 CST 1970  m2.birth:Wed May 03 00:00:00 CST 3922

总结

使用场景：需要到大量相同对象，但内部内容或结构可能进行修改。思考上述被复制对象中如果含多层引用，克隆包含循环引用的复杂对象可能会非常麻烦。

代码下载

代码下载