组合模式(Composite Pattern)也叫合成模式,有时又叫做部分-整体模式(Part-Whole),
主要是用来描述部分与整体的关系:
定义:
Compose objects into tree structures to represent part-whole hierarchies.Composite lets clients treat individual objects and compositions of objects uniformly.(将对象组合成树形结构以表示“部分-整体”的层次结构,使得用户对单个对象和组合对象的使用具有一致性。)
举个最常见的例子,公司组织架构就是一个典型的树状结构(网上截取图):
我们一般会这样设计组织架构,看代码实现
首先根节点IROOT
/**
* 根节点
* @author shuliangzhao
* @Title: IRoot
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:37
*/
public interface IRoot {
//得到总经理的信息
public String getInfo();
//总经理下边要有小兵,那要能增加小兵,比如研发部总经理,这是个树枝节点
public void add(IBranch branch);
//那要能增加树叶节点
public void add(ILeaf leaf);
//既然能增加,那还要能够遍历,不可能总经理不知道他手下有哪些人
public ArrayList getSubordinateInfo();
}
ROOT实现类
/**
* @author shuliangzhao
* @Title: Root
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:40
*/
public class Root implements IRoot {
//保存根节点下的树枝节点和树叶节点,Subordinate的意思是下级
private ArrayList subordinateList = new ArrayList();
//根节点的名称
private String name = "";
//根节点的职位
private String position = "";
//根节点的薪水
private int salary = 0;
//通过构造函数传递进来总经理的信息
public Root(String name,String position,int salary){
this.name = name;
this.position = position;
this.salary = salary;
}
@Override
public String getInfo() {
String info = "";
info = "名称:"+ this.name;;
info = info + " 职位:" + this.position;
info = info + " 薪水: " + this.salary;
return info;
}
@Override
public void add(IBranch branch) {
this.subordinateList.add(branch);
}
@Override
public void add(ILeaf leaf) {
this.subordinateList.add(leaf);
}
@Override
public ArrayList getSubordinateInfo() {
return this.subordinateList;
}
}
分之节点IBranch
/**
* 分之节点
* @author shuliangzhao
* @Title: IBranch
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:38
*/
public interface IBranch {
//获得信息
public String getInfo();
//增加数据节点,例如研发部下设的研发一组
public void add(IBranch branch);
//增加叶子节点
public void add(ILeaf leaf);
//获得下级信息
public ArrayList getSubordinateInfo();
}
分之节点实现Branch
/**
* @author shuliangzhao
* @Title: Branch
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:43
*/
public class Branch implements IBranch {
//保存根节点下的树枝节点和树叶节点,Subordinate的意思是下级
private ArrayList subordinateList = new ArrayList();
//根节点的名称
private String name = "";
//根节点的职位
private String position = "";
//根节点的薪水
private int salary = 0;
public Branch(String name,String position,int salary){
this.name = name;
this.position = position;
this.salary = salary;
}
@Override
public String getInfo() {
String info = "";
info = "名称:"+ this.name;;
info = info + " 职位:" + this.position;
info = info + " 薪水: " + this.salary;
return info;
}
@Override
public void add(IBranch branch) {
this.subordinateList.add(branch);
}
@Override
public void add(ILeaf leaf) {
this.subordinateList.add(leaf);
}
@Override
public ArrayList getSubordinateInfo() {
return this.subordinateList;
}
}
叶子节点ILeaf
/**
* 叶子节点
* @author shuliangzhao
* @Title: ILeaf
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:39
*/
public interface ILeaf {
//获得自己的信息
public String getInfo();
}
Leaf实现类
/**
* @author shuliangzhao
* @Title: Leaf
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:45
*/
public class Leaf implements ILeaf {
//根节点的名称
private String name = "";
//根节点的职位
private String position = "";
//根节点的薪水
private int salary = 0;
public Leaf(String name,String position,int salary){
this.name = name;
this.position = position;
this.salary = salary;
}
@Override
public String getInfo() {
String info = "";
info = "名称:"+ this.name;;
info = info + " 职位:" + this.position;
info = info + " 薪水: " + this.salary;
return info;
}
}
客户端Client
/**
* @author shuliangzhao
* @Title: Client
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 22:49
*/
public class Client {
public static void main(String[] args) {
//首先产生了一个根节点
IRoot ceo = new Root("Jon","总经理",100000);
//产生三个部门经理,也就是树枝节点
IBranch developDep = new Branch("张三","研发部门经理",10000);
IBranch salesDep = new Branch("李四","销售部门经理",20000);
IBranch financeDep = new Branch("王五","财务部经理",30000);
//再把三个小组长产生出来
IBranch firstDevGroup = new Branch("赵六","开发一组组长",5000);
IBranch secondDevGroup = new Branch("张飞","开发二组组长",6000);
//剩下的就是我们这些小兵了,就是路人甲、路人乙
ILeaf a = new Leaf("a","开发人员",2000);
ILeaf b = new Leaf("b","开发人员",2000);
ILeaf c = new Leaf("c","开发人员",2000);
ILeaf d = new Leaf("d","开发人员",2000);
ILeaf e = new Leaf("e","开发人员",2000);
ILeaf f = new Leaf("f","开发人员",2000);
ILeaf g = new Leaf("g","开发人员",2000);
ILeaf h = new Leaf("h","销售人员",5000);
ILeaf i = new Leaf("i","销售人员",4000);
ILeaf j = new Leaf("j","财务人员",5000);
ILeaf k = new Leaf("k","CEO秘书",8000);
ILeaf zhengLaoLiu = new Leaf("唐三","研发部副总",20000);
//ceo下属员工
ceo.add(developDep);
ceo.add(salesDep);
ceo.add(financeDep);
ceo.add(k);
//定义研发部门下的结构
developDep.add(firstDevGroup);
developDep.add(secondDevGroup);
//研发部经理下还有一个副总
developDep.add(zhengLaoLiu);
//看看开发两个开发小组下有什么
firstDevGroup.add(a);
firstDevGroup.add(b);
firstDevGroup.add(c);
secondDevGroup.add(d);
secondDevGroup.add(e);
secondDevGroup.add(f);
//再看销售部下的人员情况
salesDep.add(h);
salesDep.add(i);
//最后一个财务
financeDep.add(j);
System.out.println(ceo.getInfo());
getAllsubordinateList(ceo.getSubordinateInfo());
}
private static void getAllsubordinateList(ArrayList subordinateInfo) {
for (int i = 0;i<subordinateInfo.size();i++) {
Object o = subordinateInfo.get(i);
if (o instanceof Leaf) {
Leaf leaf = (Leaf) o;
System.out.println(leaf.getInfo());
}else {
IBranch iBranch = (IBranch) o;
System.out.println(iBranch.getInfo());
getAllsubordinateList(iBranch.getSubordinateInfo());
}
}
}
}
运行结果
名称:Jon 职位:总经理 薪水: 100000
名称:张三 职位:研发部门经理 薪水: 10000
名称:赵六 职位:开发一组组长 薪水: 5000
名称:a 职位:开发人员 薪水: 2000
名称:b 职位:开发人员 薪水: 2000
名称:c 职位:开发人员 薪水: 2000
名称:张飞 职位:开发二组组长 薪水: 6000
名称:d 职位:开发人员 薪水: 2000
名称:e 职位:开发人员 薪水: 2000
名称:f 职位:开发人员 薪水: 2000
名称:唐三 职位:研发部副总 薪水: 20000
名称:李四 职位:销售部门经理 薪水: 20000
名称:h 职位:销售人员 薪水: 5000
名称:i 职位:销售人员 薪水: 4000
名称:王五 职位:财务部经理 薪水: 30000
名称:j 职位:财务人员 薪水: 5000
名称:k 职位:CEO秘书 薪水: 8000
我们这样设计看起来代码比较臃肿,而且有很多重复代码。
现在看我们更改过的设计如下:
Corp 抽象类
/**
* @author shuliangzhao
* @Title: Corp
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 23:23
*/
public abstract class Corp {
//公司每个人都有名称
private String name = "";
//公司每个人都职位
private String position = "";
//公司每个人都有薪水
private int salary =0;
public Corp(String _name,String _position,int _salary){
this.name = _name;
this.position = _position;
this.salary = _salary;
}
//获得员工信息
public String getInfo(){
String info = "";
info = "姓名:" + this.name;
info = info + " 职位:"+ this.position;
info = info + " 薪水:" + this.salary;
return info;
}
}
Branch
/**
* @author shuliangzhao
* @Title: Branch
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 23:26
*/
public class Branch extends Corp {
//领导下边有哪些下级领导和小兵
ArrayList<Corp> subordinateList = new ArrayList<Corp>();
public Branch(String _name, String _position, int _salary) {
super(_name, _position, _salary);
}
//增加一个下属,可能是小头目,也可能是个小兵
public void addSubordinate(Corp corp) {
this.subordinateList.add(corp);
}
//我有哪些下属
public ArrayList<Corp> getSubordinate() {
return this.subordinateList;
}
}
Leaf
/**
* @author shuliangzhao
* @Title: Leaf
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 23:27
*/
public class Leaf extends Corp {
public Leaf(String _name, String _position, int _salary) {
super(_name, _position, _salary);
}
}
客户端
/**
* @author shuliangzhao
* @Title: Client
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 23:27
*/
public class Client {
public static void main(String[] args) {
//首先产生了一个根节点
Branch ceo = new Branch("Jon","总经理",100000);
//产生三个部门经理,也就是树枝节点
Branch developDep = new Branch("张三","研发部门经理",10000);
Branch salesDep = new Branch("李四","销售部门经理",20000);
Branch financeDep = new Branch("王五","财务部经理",30000);
//再把三个小组长产生出来
Branch firstDevGroup = new Branch("赵六","开发一组组长",5000);
Branch secondDevGroup = new Branch("张飞","开发二组组长",6000);
//剩下的就是我们这些小兵了,就是路人甲、路人乙
Leaf a = new Leaf("a","开发人员",2000);
Leaf b = new Leaf("b","开发人员",2000);
Leaf c = new Leaf("c","开发人员",2000);
Leaf d = new Leaf("d","开发人员",2000);
Leaf e = new Leaf("e","开发人员",2000);
Leaf f = new Leaf("f","开发人员",2000);
Leaf g = new Leaf("g","开发人员",2000);
Leaf h = new Leaf("h","销售人员",5000);
Leaf i = new Leaf("i","销售人员",4000);
Leaf j = new Leaf("j","财务人员",5000);
Leaf k = new Leaf("k","CEO秘书",8000);
Leaf zhengLaoLiu = new Leaf("唐三","研发部副总",20000);
//ceo下属员工
ceo.addSubordinate(developDep);
ceo.addSubordinate(salesDep);
ceo.addSubordinate(financeDep);
ceo.addSubordinate(k);
//定义研发部门下的结构
developDep.addSubordinate(firstDevGroup);
developDep.addSubordinate(secondDevGroup);
//研发部经理下还有一个副总
developDep.addSubordinate(zhengLaoLiu);
//看看开发两个开发小组下有什么
firstDevGroup.addSubordinate(a);
firstDevGroup.addSubordinate(b);
firstDevGroup.addSubordinate(c);
secondDevGroup.addSubordinate(d);
secondDevGroup.addSubordinate(e);
secondDevGroup.addSubordinate(f);
//再看销售部下的人员情况
salesDep.addSubordinate(h);
salesDep.addSubordinate(i);
//最后一个财务
financeDep.addSubordinate(j);
System.out.println(ceo.getInfo());
System.out.println(getTreeInfo(ceo));
}
private static String getTreeInfo(Branch ceo) {
ArrayList<Corp> subordinate = ceo.getSubordinate();
String info = "";
for (Corp s:subordinate) {
if (s instanceof Leaf) {
info = info+s.getInfo()+"
";
}else {
info = info+s.getInfo()+"
" + getTreeInfo((Branch)s);
}
}
return info;
}
}
运行结果
姓名:Jon 职位:总经理 薪水:100000
姓名:张三 职位:研发部门经理 薪水:10000
姓名:赵六 职位:开发一组组长 薪水:5000
姓名:a 职位:开发人员 薪水:2000
姓名:b 职位:开发人员 薪水:2000
姓名:c 职位:开发人员 薪水:2000
姓名:张飞 职位:开发二组组长 薪水:6000
姓名:d 职位:开发人员 薪水:2000
姓名:e 职位:开发人员 薪水:2000
姓名:f 职位:开发人员 薪水:2000
姓名:唐三 职位:研发部副总 薪水:20000
姓名:李四 职位:销售部门经理 薪水:20000
姓名:h 职位:销售人员 薪水:5000
姓名:i 职位:销售人员 薪水:4000
姓名:王五 职位:财务部经理 薪水:30000
姓名:j 职位:财务人员 薪水:5000
姓名:k 职位:CEO秘书 薪水:8000
组合模式的优点
1.高层模块调用简单
2.节点自由增加
题外话,如果我们想找到每个节点的父节点我们的Corp类可以从新设计
增加一个熟悉parent
升级版Crop
/**
* @author shuliangzhao
* @Title: Corp
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 23:23
*/
public abstract class Corp {
//公司每个人都有名称
private String name = "";
//公司每个人都职位
private String position = "";
//公司每个人都有薪水
private int salary =0;
private Corp parent;
public Corp getParent() {
return parent;
}
public void setParent(Corp parent) {
this.parent = parent;
}
public Corp(String _name, String _position, int _salary){
this.name = _name;
this.position = _position;
this.salary = _salary;
}
//获得员工信息
public String getInfo(){
String info = "";
info = "姓名:" + this.name;
info = info + " 职位:"+ this.position;
info = info + " 薪水:" + this.salary;
return info;
}
}
子节点实现
/**
* @author shuliangzhao
* @Title: Branch
* @ProjectName design-parent
* @Description: TODO
* @date 2019/6/18 23:26
*/
public class Branch extends Corp {
//领导下边有哪些下级领导和小兵
ArrayList<Corp> subordinateList = new ArrayList<Corp>();
public Branch(String _name, String _position, int _salary) {
super(_name, _position, _salary);
}
//增加一个下属,可能是小头目,也可能是个小兵
public void addSubordinate(Corp corp) {
super.setParent(this);
this.subordinateList.add(corp);
}
//我有哪些下属
public ArrayList<Corp> getSubordinate() {
return this.subordinateList;
}
}
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