package Composite;
public abstract class Component {
    //个体和整体都具有的共享
    public void doSomething(){
        //编写业务逻辑
    }
}

package Composite;

import java.util.ArrayList;

public class Composite extends Component{
    //构件容器
    private ArrayList<Component> componentArrayList=new ArrayList<Component>();
    //增加一个叶子构件或树枝构件
    public void add(Component component){
        this.componentArrayList.add(component);
    }
    //删除一个叶子构件或树枝构件
    public void remove(Component component){
        this.componentArrayList.remove(component);
    }
    //获得分支下的所有叶子构件和树枝构件
    public ArrayList<Component> getChileren(){
        return this.componentArrayList;
    }
}

package Composite;

public class Leaf extends Component{
    /*
     * 可以重写父类方法
     *    public void doSomething(){
     *  
     *  }
     */
}

package Composite;

public class Main {
    public static void main(String[] args){
        //创建一个根节点
        Composite root=new Composite();
        root.doSomething();
        //创建一个树枝构件
        Composite branch=new Composite();
        //创建一个叶子节点
        Leaf leaf=new Leaf();
        //建立整体
        root.add(branch);
        branch.add(leaf);
    }
    public static void display(Composite root){
        for(Component c:root.getChileren()){
            if(c instanceof Leaf){//叶子节点
                c.doSomething();
            }else{
                display((Composite)c);
            }
        }
    }
}