10.16

装饰器模式

下面是一个简单的Java代码示例，展示了装饰器模式的实现

// 抽象组件接口
interface Component {
    void operation();
}

// 具体组件类
class ConcreteComponent implements Component {
    @Override
    public void operation() {
        System.out.println("ConcreteComponent operation");
    }
}

// 抽象装饰器类
abstract class Decorator implements Component {
    protected Component component;

    public Decorator(Component component) {
        this.component = component;
    }

    @Override
    public void operation() {
        component.operation();
    }
}

// 具体装饰器类A
class ConcreteDecoratorA extends Decorator {
    public ConcreteDecoratorA(Component component) {
        super(component);
    }

    @Override
    public void operation() {
        super.operation();
        addBehavior();
    }

    private void addBehavior() {
        System.out.println("ConcreteDecoratorA add behavior");
    }
}

// 具体装饰器类B
class ConcreteDecoratorB extends Decorator {
    public ConcreteDecoratorB(Component component) {
        super(component);
    }

    @Override
    public void operation() {
        super.operation();
        addBehavior();
    }

    private void addBehavior() {
        System.out.println("ConcreteDecoratorB add behavior");
    }
}

// 客户端代码
public class DecoratorPatternExample {
    public static void main(String[] args) {
        // 创建具体组件对象
        Component component = new ConcreteComponent();

        // 创建具体装饰器对象，并传入具体组件对象
        Decorator decoratorA = new ConcreteDecoratorA(component);
        Decorator decoratorB = new ConcreteDecoratorB(decoratorA);

        // 调用装饰器对象的方法
        decoratorB.operation();
    }
}