当复制即创新：深入探究Java原型模式的魅力

public class Shape implements Cloneable {
    private String id;
    private String type;
    public void draw() {
        System.out.println("Shape: " + type + ", id: " + id);
    }
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
    public Object clone() {
        Object clone = null;
        try {
            clone = super.clone();
        } catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
        return clone;
    }
}
public class Rectangle extends Shape {
    public Rectangle() {
        setType("Rectangle");
    }
    public void draw() {
        System.out.println("Inside Rectangle::draw() method.");
    }
}
public class Square extends Shape {
    public Square() {
        setType("Square");
    }
    public void draw() {
        System.out.println("Inside Square::draw() method.");
    }
}
public class ShapeCache {
    private static Map<String, Shape> shapeMap = new HashMap<>();
    public static Shape getShape(String shapeId) {
        Shape cachedShape = shapeMap.get(shapeId);
        return (Shape) cachedShape.clone();
    }
    public static void loadCache() {
        Rectangle rectangle = new Rectangle();
        rectangle.setId("1");
        shapeMap.put(rectangle.getId(), rectangle);
        Square square = new Square();
        square.setId("2");
        shapeMap.put(square.getId(), square);
    }
}
public class PrototypePatternDemo {
    public static void main(String[] args) {
        ShapeCache.loadCache();
        Shape clonedShape = ShapeCache.getShape("1");
        System.out.println("Shape : " + clonedShape.getType());
        Shape clonedShape2 = ShapeCache.getShape("2");
        System.out.println("Shape : " + clonedShape2.getType());
    }
}

import java.io.*;
public class Person implements Serializable, Cloneable {
    private String name;
    private int age;
    private Address address;
    public Person(String name, int age, Address address) {
        this.name = name;
        this.age = age;
        this.address = address;
    }
    @Override
    public Person clone() {
        try {
            Person clone = (Person) super.clone();
            clone.address = address.clone();
            return clone;
        } catch (CloneNotSupportedException e) {
            throw new RuntimeException(e);
        }
    }
    private static class Address implements Serializable, Cloneable {
        private String city;
        private String street;
        public Address(String city, String street) {
            this.city = city;
            this.street = street;
        }
        @Override
        public Address clone() {
            try {
                return (Address) super.clone();
            } catch (CloneNotSupportedException e) {
                throw new RuntimeException(e);
            }
        }
    }
    public static void main(String[] args) {
        Address address = new Address("New York", "5th Avenue");
        Person person1 = new Person("John", 30, address);
        Person person2 = person1.clone();
        person2.setName("Jane");
        person2.setAge(25);
        person2.getAddress().setCity("Los Angeles");
        person2.getAddress().setStreet("Beverly Hills");
        System.out.println(person1);
        System.out.println(person2);
    }
    // Getters and setters
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public Address getAddress() {
        return address;
    }
    public void setAddress(Address address) {
        this.address = address;
    }
    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", address=" + address +
                '}';
    }
}