【设计模式学习笔记】组合模式

妖狐艹你老母 2022-03-29 09:52 128阅读 0赞

> 组合模式，适用于树状结构。模式有三个角色：组合部件，合成模块，叶子。组合部件是组合其余两者的父类。它是一个提供公共属性，方法的抽象类。合成模块用于合成最终的组合对象，叶子节点是组合部件的底层，也就相当于树枝与树叶。该模式又为安全模式和透明模式。两者却别在于父类是否提供用于合成组件的所有方法。

### 文章目录 ###

[1 透明模式：][1]

[1.2 抽象组合部件][1.2]

[1.3 合成模块][1.3]

[1.4 叶子][1.4]

[1.5 分配人员并显示][1.5]

[1.6 结果][1.6]

[2 安全模式][2]

[2.2 抽象组合部件][2.2]

[2.3 合成模块][2.3]

[2.4 叶子][2.4]

[2.5 分配人员并显示][2.5]

[2.6 结果][2.6]

[参考][Link 1]

好了，我们的公司最近招人。那么就以人事的结构为例吧。  
首先zhangxu是这个虚拟公司的BOSS。下面有两个经理：lisi,wangwu。还有几个招聘的小弟。

# 1 透明模式： #

## 1.2 抽象组合部件 ##

package composite.compositiontransparent;
    
    import java.util.ArrayList;
    import java.util.List;
    
    public abstract class Component {
    	protected String name;
    	private List<Component> list = new ArrayList<>();
    
    	public abstract void addSubNode(Component component);
    	public void getInfo() {
    		System.out.println(this.name);
    	}
    
    	public List<Component> getList() {
    		return list;
    	}
    	public void setList(List<Component> list) {
    		this.list = list;
    	}
    
    }

## 1.3 合成模块 ##

package composite.compositiontransparent;
    
    public class Composite extends Component{
    
    
    	@Override
    	public void addSubNode(Component component) {
    		super.getList().add(component);
    	}
    
    	public Composite(String name) {
    		super.name = name;
    	}
    
    }

## 1.4 叶子 ##

package composite.compositiontransparent;
    
    public class Leaf extends Component {
    
    	@Override
    	public void addSubNode(Component component) {
    		System.out.println("叶子节点不能添加节点");
    	}
    
    	public Leaf(String name) {
    		super.name = name;
    	}
    
    }

## 1.5 分配人员并显示 ##

package composite.compositiontransparent;
    
    public class Test {
    	public static void main(String[] args) {
    		Component component1 = new Composite("zhangxu");
    		Component component2 = new Composite("lisi");
    		Component component3 = new Composite("wangwu");
    		Component component4 = new Leaf("xiaozhen");
    		Component component5 = new Leaf("xiaochen");
    		Component component6 = new Leaf("xiaochenchen");
    
    		component1.addSubNode(component2);
    		component1.addSubNode(component3);
    		component2.addSubNode(component4);
    		component3.addSubNode(component5);
    		component1.addSubNode(component6);
    
    		getNodes(component1);
    	}
    
    	public static void getNodes(Component component) {
    		component.getInfo();
    		if(component.getList()==null || component.getList().size() == 0) {
    			return;
    		}
    		for(Component component2 :component.getList()) {
    			getNodes(component2);
    		}
    	}
    }

## 1.6 结果 ##

![20181215210432838.png][]

# 2 安全模式 #

## 2.2 抽象组合部件 ##

package composite.compostitionsafe;
    
    public abstract class Component {
    	protected String name;
    	protected String pname;
    
    	public void getInfo() {
    		System.out.println(this.name+"/属于："+pname);
    	}
    }

##  2.3 合成模块 ##

package composite.compostitionsafe;
    
    import java.util.ArrayList;
    import java.util.List;
    
    public class Composite extends Component{
    	private List<Component> list = new ArrayList<>();
    
    	public void addSubNode(Component component) {
    		component.pname = this.name;
    		list.add(component);
    	}
    
    	public void getNodes(){
    		getInfo();
    		for(Component component :this.list){
    			if(Leaf.class.isInstance(component)){
    				((Leaf)component).getInfo();
    				continue;
    			}
    			((Composite) component).getNodes();
    		}
    	}
    
    	public Composite(String name) {
    		super.name = name;
    	}
    
    }

## 2.4 叶子 ##

package composite.compostitionsafe;
    
    public class Leaf extends Component {
    
    	public Leaf(String name) {
    		super.name = name;
    	}
    
    }

##  2.5 分配人员并显示 ##

package composite.compostitionsafe;
    
    public class Test {
    	public static void main(String[] args) {
    		Composite composite1 = new Composite("zhangxu");
    		Composite composite2 = new Composite("lisi");
    		Composite composite3 = new Composite("wangwu");
    		Leaf leaf1 = new Leaf("xiaozhen");
    		Leaf leaf2 = new Leaf("xiaochen");
    
    		composite1.addSubNode(composite2);
    		composite1.addSubNode(composite3);
    		composite2.addSubNode(leaf1);
    		composite3.addSubNode(leaf2);
    
    		composite1.getNodes();
    	}
    
    }

##  2.6 结果 ##

![20181215210421719.png][]

## 参考 ##

【菜鸟教程】：[http://www.runoob.com/design-pattern/composite-pattern.html][http_www.runoob.com_design-pattern_composite-pattern.html]

本文原文地址： [https://blog.csdn.net/baidu\_30325009/article/details/85018521][https_blog.csdn.net_baidu_30325009_article_details_85018521]

[1]: https://blog.csdn.net/baidu_30325009/article/details/85018521#1__8
[1.2]: https://blog.csdn.net/baidu_30325009/article/details/85018521#12__9
[1.3]: https://blog.csdn.net/baidu_30325009/article/details/85018521#13__36
[1.4]: https://blog.csdn.net/baidu_30325009/article/details/85018521#14__55
[1.5]: https://blog.csdn.net/baidu_30325009/article/details/85018521#15__73
[1.6]: https://blog.csdn.net/baidu_30325009/article/details/85018521#16__107
[2]: https://blog.csdn.net/baidu_30325009/article/details/85018521#2__110
[2.2]: https://blog.csdn.net/baidu_30325009/article/details/85018521#22__111
[2.3]: https://blog.csdn.net/baidu_30325009/article/details/85018521#23__125
[2.4]: https://blog.csdn.net/baidu_30325009/article/details/85018521#24__158
[2.5]: https://blog.csdn.net/baidu_30325009/article/details/85018521#25__171
[2.6]: https://blog.csdn.net/baidu_30325009/article/details/85018521#26__194
[Link 1]: https://blog.csdn.net/baidu_30325009/article/details/85018521#_197
[20181215210432838.png]: /images/20220329/afe1fd78565a4d0f8125dd60c344adb0.png
[20181215210421719.png]: /images/20220329/fe07fc43167e40a2b9dc296a93f1240d.png
[http_www.runoob.com_design-pattern_composite-pattern.html]: http://www.runoob.com/design-pattern/composite-pattern.html
[https_blog.csdn.net_baidu_30325009_article_details_85018521]: https://blog.csdn.net/baidu_30325009/article/details/85018521