实验10：组合模式

[实验任务一]：组合模式

用透明组合模式实现教材中的“文件夹浏览”这个例子。

 

1.类图

 

 

2. 源代码

public abstract  class  Component {

    private String name = "";

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

    protected String getName(){
        return name;
    }

    protected  abstract void printStruct(String prefix);
    /**
     * 向组合对象中加入组件对象
     * 叶子对象没有该功能
     *
     * */
    protected  void addChild(Component component) {
        throw new UnsupportedOperationException("此对象不支持addChild该功能");
    }
    /**
     * 向组合对象中移除组件对象
     * 叶子对象没有该功能
     *
     * */
    protected  void removeChild(Component component){
        throw new UnsupportedOperationException("此对象不支持removeChild该功能");
    }
}

public class Leaf extends Component {

    public Leaf(String name){
        super(name);
    }
    /***
     * 打印对应的叶子结构
     * @param  prefix 前缀 实现向后缩进
     *
     */
    public void printStruct(String prefix){
        System.out.println(prefix + "-" + super.getName());
    }
}

public class Composite extends Component{

    List<Component> componentList = new ArrayList<>();

    public Composite(String name) {
        super(name);
    }

    @Override
    protected void printStruct(String prefix) {
        System.out.println(prefix + "+"  + getName());
        if (componentList != null) {
            //打印其叶子节点,缩进一个空格
            for(Component component: componentList) {
                component.printStruct(prefix + prefix);
            }
        }
    }

    @Override
    protected void addChild(Component component) {
        this.componentList.add(component);
    }

    @Override
    protected void removeChild(Component component) {
        this.componentList.remove(component);
    }
}

public class Client {
    public static void main(String[] args) {
        //组合对象  作为根节点
        Component root  = new Composite("服装");
        //组合对象
        Component composite1 = new Composite("夏装");
        Component composite2 = new Composite("冬装");
        //叶子节点
        Leaf leaf1 = new Leaf("裙子");
        Leaf leaf2 = new Leaf("背心");
        Leaf leaf3 = new Leaf("棉衣");

        root.addChild(composite1);
        root.addChild(composite2);

        composite1.addChild(leaf1);
        composite1.addChild(leaf2);
        composite2.addChild(leaf3);

        root.printStruct("");

    }
}