设计模式学习之装饰模式

 1.名词解释：

装饰模式：动态的给一个对象添加一个额外的职责，就增加功能来说，装饰模式比生成子类更为灵活。装饰模式是为已有功能动态地添加更多功能的一种方式。

 

2.代码示例：

组件类：
package DesignPattern.DecoratorPattern;

public abstract class Component {

	public abstract void operation();
}

 

具体的对象接口类
package DesignPattern.DecoratorPattern;

public class ConcreateComponent extends Component {

	@Override
	public void operation() {
		// TODO Auto-generated method stub
		System.out.println("ConcreateComponent.operation is process...");
	}
}

 

装饰类：
package DesignPattern.DecoratorPattern;

public class Decorator extends Component{

    protected Component component;
	
	public void setComponent(Component component) {
		this.component = component;
	}
	
	@Override
	public void operation() {
		// TODO Auto-generated method stub
		if(this.component != null) {
			component.operation();
		}
	}
}

 

package DesignPattern.DecoratorPattern;

public class ConcreateDecoratorA extends Decorator{

	public void operation() {
		super.operation();
		System.out.println("ConcreateDecoratorA.operation is process...");
	}

}

package DesignPattern.DecoratorPattern;

public class ConcreateDecoratorB extends Decorator{

	public void operation() {
		super.operation();
		this.addBehavior();
		System.out.println("ConcreateDecoratorB.operation is process...");
	}
	
	private void addBehavior() {
		System.out.println("ConcreateDecoratorB.addBehavior is process...");
	}
}

 

主控程序类：
package DesignPattern.DecoratorPattern;

public class Client {

	public static void main(String[] args) {
		ConcreateComponent c = new ConcreateComponent();
		ConcreateDecoratorA d1 = new ConcreateDecoratorA();
		ConcreateDecoratorB d2 = new ConcreateDecoratorB();
		d1.setComponent(c);
		d2.setComponent(d1);
		d2.operation();
	}
}