目录

• 介绍
• 角色
• Java语言提供的clone()方法
• 代码演示―克隆羊
  • 结论
• 深浅拷贝
  • 深浅拷贝探讨
  • 实现深克隆的方式一 ： 手动对引用对象进行克隆
  • 实现深克隆的方式一 ：序列化
• 原型模式对单例模式的破坏
• 优缺点
• 适用场景
• 原型模式在Spring中的应用场景
• 总结

//实现Cloneable接口@Datapublic class Sheep implements Cloneable{    private String name;    private Integer age;    //重写Object的clone方法    @Override    protected Object clone() throws CloneNotSupportedException     {        Sheep sheep=null;        sheep=(Sheep)super.clone();        return sheep;    }}

        //创建原型对象        Sheep sheep=new Sheep();        sheep.setAge(3);        sheep.setName("肖恩");        //克隆        Sheep sheep1 = sheep.clone();        Sheep sheep2=sheep.clone();        System.out.println(sheep1);        System.out.println(sheep2);        System.out.println(sheep1==sheep2);

protected native Object clone() throws CloneNotSupportedException;

@Data@AllArgsConstructor@NoArgsConstructorpublic class Pig {    String name;    Integer age;}

//实现Cloneable接口@Datapublic class Sheep implements Cloneable{    private String name;    private Integer age;    private  Pig pig;    //重写Object的clone方法    @Override    protected Sheep clone() throws CloneNotSupportedException    {        Sheep sheep=null;        sheep=(Sheep)super.clone();        return sheep;    }}

public class test{    @Test    public void test() throws CloneNotSupportedException {        //创建原型对象        Sheep sheep=new Sheep();        sheep.setAge(3);        sheep.setName("肖恩");        sheep.setPig(new Pig("大忽悠",3));        //克隆        Sheep sheep1 = sheep.clone();        Sheep sheep2=sheep.clone();        System.out.println(sheep1);        System.out.println(sheep2);        System.out.println(sheep1==sheep2);        System.out.println("==============================");        System.out.println(sheep1.getPig()==sheep2.getPig());    }}

@Data@AllArgsConstructor@NoArgsConstructorpublic class Pig implements Cloneable{    String name;    Integer age;    @Override    protected Object clone() throws CloneNotSupportedException {        return super.clone();    }}

//实现Cloneable接口@Datapublic class Sheep implements Cloneable{    private String name;    private Integer age;    private  Pig pig;    //重写Object的clone方法    @Override    protected Sheep clone() throws CloneNotSupportedException    {        Sheep sheep=null;        sheep=(Sheep)super.clone();        sheep.pig=(Pig)sheep.pig.clone();        return sheep;    }}

@Data@AllArgsConstructor@NoArgsConstructorpublic class Pig implements Serializable{    String name;    Integer age;}

//实现Cloneable接口@Datapublic class Sheep implements Serializable{    private String name;    private Integer age;    private  Pig pig; //序列化方式完成深拷贝    public Sheep deepClone() throws IOException, ClassNotFoundException {        //先将要序列化的对象写入流中        ByteArrayOutputStream baot=new ByteArrayOutputStream();        //ObjectOutputStream构造函数的参数是，将对象流写入到哪里        ObjectOutputStream oot=new ObjectOutputStream(baot);          oot.writeObject(this);          //将序列化的对象从流中读取出来        ByteArrayInputStream bait=new ByteArrayInputStream(baot.toByteArray());        ObjectInputStream oit=new ObjectInputStream(bait);        return (Sheep) oit.readObject();    }}

public class HungrySingleton implements Serializable, Cloneable {    private final static HungrySingleton hungrySingleton;    static {        hungrySingleton = new HungrySingleton();    }    private HungrySingleton()     {}    public static HungrySingleton getInstance() {        return hungrySingleton;    }    private Object readResolve() {        return hungrySingleton;    }    @Override    protected Object clone() throws CloneNotSupportedException {        return super.clone();    }}

public class Test {    public static void main(String[] args) throws CloneNotSupportedException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {        HungrySingleton hungrySingleton = HungrySingleton.getInstance();        Method method = hungrySingleton.getClass().getDeclaredMethod("clone");        method.setAccessible(true);        HungrySingleton cloneHungrySingleton = (HungrySingleton) method.invoke(hungrySingleton);        System.out.println(hungrySingleton);        System.out.println(cloneHungrySingleton);    }}

    @Override    protected Object clone() throws CloneNotSupportedException {        return getInstance();    }