Java Prototype

The Prototype pattern is a creational design pattern that lets you copy existing objects without making your code dependent on their classes. This pattern is especially useful when the construction of an object is costly or complex.

定义原型接口

java

        public interface Prototype extends Cloneable {
    Prototype clone();
}

创建具体原型类

java

        public class ConcretePrototype implements Prototype {
    private String name;

    public ConcretePrototype(String name) {
        this.name = name;
    }

    @Override
    public Prototype clone() {
        try {
            return (Prototype) super.clone();
        } catch (CloneNotSupportedException e) {
            e.printStackTrace();
            return null;
        }
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "ConcretePrototype{name='" + name + "'}";
    }
}

使用原型模式

java

        public class PrototypePatternDemo {
    public static void main(String[] args) {
        ConcretePrototype prototype1 = new ConcretePrototype("Prototype 1");
        ConcretePrototype prototype2 = (ConcretePrototype) prototype1.clone();

        System.out.println(prototype1);
        System.out.println(prototype2);

        prototype2.setName("Prototype 2");
        System.out.println(prototype1);
        System.out.println(prototype2);
    }
}