《大話設(shè)計(jì)模式》閱讀筆記和總結(jié)溅漾。原書是C#編寫的,本人用Java實(shí)現(xiàn)了一遍著榴,包括每種設(shè)計(jì)模式的UML圖實(shí)現(xiàn)和示例代碼實(shí)現(xiàn)添履。
目錄:設(shè)計(jì)模式
Github地址:DesignPattern
說明
定義:組合模式(Composite),將對(duì)象組合成樹形結(jié)構(gòu)以表示“部分-整體”的層次結(jié)構(gòu)兄渺。組合模式使得用戶對(duì)單個(gè)對(duì)象和組合對(duì)象的使用具有一致性缝龄。
UML圖:
代碼實(shí)現(xiàn):
Component為組合中的對(duì)象聲明接口,在適當(dāng)情況下挂谍,實(shí)現(xiàn)所有類共有接口的默認(rèn)行為。聲明一個(gè)接口用于訪問和管理Component子部件
abstract class Component{
protected String name;
public Component(String name) {
this.name = name;
}
public abstract void Add(Component c);
public abstract void Remove(Component c);
public abstract void Display(int depth);
}
Leaf在組合中表示葉節(jié)點(diǎn)對(duì)象瞎饲,葉節(jié)點(diǎn)沒有子節(jié)點(diǎn)
class Leaf extends Component{
public Leaf(String name) {
super(name);
}
@Override
public void Add(Component c) {
System.out.println("Cannot add to a leaf");
}
@Override
public void Remove(Component c) {
System.out.println("Cannot remove to a leaf");
}
/**
* 頁節(jié)點(diǎn)的具體方法口叙,此處是顯示其名稱和級(jí)別
* @param depth
*/
@Override
public void Display(int depth) {
for (int i = 0; i < depth; i++) {
System.out.print("-");
}
System.out.println(name);
}
}
Composite定義枝節(jié)點(diǎn)行為,用于存儲(chǔ)子部件嗅战,在Component接口中實(shí)現(xiàn)與子部件有關(guān)的操作妄田,比如增加Add和remove刪除
class Composite extends Component{
private List<Component> children = new ArrayList<>();
public Composite(String name) {
super(name);
}
@Override
public void Add(Component c) {
children.add(c);
}
@Override
public void Remove(Component c) {
children.remove(c);
}
@Override
public void Display(int depth) {
for (int i = 0; i < depth; i++) {
System.out.print("-");
}
System.out.println(name);
for (Component component : children) {
component.Display(depth+2);
}
}
}
客戶端代碼
public class CompositePattern {
public static void main(String[] args) {
Composite root = new Composite("root");
root.Add(new Leaf("Leaf A"));
root.Add(new Leaf("Leaf B"));
Composite comp = new Composite("Composite X");
comp.Add(new Leaf("Leaf XA"));
comp.Add(new Leaf("Leaf XB"));
root.Add(comp);
Composite comp2 = new Composite("Composite XY");
comp2.Add(new Leaf("Leaf XYA"));
comp2.Add(new Leaf("Leaf XYB"));
comp.Add(comp2);
root.Add(new Leaf("Leaf C"));
Leaf leaf = new Leaf("Leaf D");
root.Add(leaf);
root.Remove(leaf);
root.Display(1);
}
}
運(yùn)行結(jié)果
-root
---Leaf A
---Leaf B
---Composite X
-----Leaf XA
-----Leaf XB
-----Composite XY
-------Leaf XYA
-------Leaf XYB
---Leaf C
示例
例子:一個(gè)公司的組織結(jié)構(gòu)圖如下圖所示,用程序來展示這個(gè)層級(jí)架構(gòu)驮捍。
UML圖:
代碼實(shí)現(xiàn):
公司類疟呐,抽象類或接口
public abstract class Company {
protected String name;
public Company(String name) {
this.name = name;
}
public abstract void Add(Company c);//增加
public abstract void Remove(Company c);//移除
public abstract void Display(int depth);//顯示
public abstract void LineOfDuty();//履行職責(zé)
}
具體公司類,實(shí)現(xiàn)接口樹枝節(jié)點(diǎn)
public class ConcreteCompany extends Company{
private List<Company> children = new ArrayList<Company>();
public ConcreteCompany(String name) {
super(name);
}
@Override
public void Add(Company c) {
children.add(c);
}
@Override
public void Remove(Company c) {
children.remove(c);
}
@Override
public void Display(int depth) {
for (int i = 0; i < depth; i++) {
System.out.print("-");
}
System.out.println(name);
for (Company company : children) {
company.Display(depth+2);
}
}
@Override
public void LineOfDuty() {
for (Company company : children) {
company.LineOfDuty();
}
}
}
HR部門
public class HRDepartment extends Company{
public HRDepartment(String name) {
super(name);
}
@Override
public void Add(Company c) {
// TODO Auto-generated method stub
}
@Override
public void Remove(Company c) {
// TODO Auto-generated method stub
}
@Override
public void Display(int depth) {
for (int i = 0; i < depth; i++) {
System.out.print("-");
}
System.out.println(name);
}
@Override
public void LineOfDuty() {
System.out.println(name+"員工招聘培訓(xùn)管理");
}
}
財(cái)務(wù)部
public class FinanceDepartment extends Company{
public FinanceDepartment(String name) {
super(name);
}
@Override
public void Add(Company c) {
// TODO Auto-generated method stub
}
@Override
public void Remove(Company c) {
// TODO Auto-generated method stub
}
@Override
public void Display(int depth) {
for (int i = 0; i < depth; i++) {
System.out.print("-");
}
System.out.println(name);
}
@Override
public void LineOfDuty() {
System.out.println(name+"公司財(cái)務(wù)收支管理");
}
}
客戶端代碼
public class Main {
public static void main(String[] args) {
ConcreteCompany root = new ConcreteCompany("北京總公司");
root.Add(new HRDepartment("總公司人力資源部"));
root.Add(new HRDepartment("總公司財(cái)務(wù)部"));
ConcreteCompany comp = new ConcreteCompany("上海華東分公司");
comp.Add(new HRDepartment("上海華東分公司人力資源部"));
comp.Add(new HRDepartment("上海華東分公司財(cái)務(wù)部"));
root.Add(comp);
ConcreteCompany comp1 = new ConcreteCompany("南京辦事處");
comp1.Add(new HRDepartment("南京辦事處人力資源部"));
comp1.Add(new HRDepartment("南京辦事處財(cái)務(wù)部"));
comp.Add(comp1);
ConcreteCompany comp2 = new ConcreteCompany("杭州辦事處");
comp2.Add(new HRDepartment("杭州辦事處人力資源部"));
comp2.Add(new HRDepartment("杭州辦事處財(cái)務(wù)部"));
comp.Add(comp2);
System.out.println("結(jié)構(gòu)圖");
root.Display(1);
System.out.println("職責(zé)");
root.LineOfDuty();
}
}
運(yùn)行結(jié)果
結(jié)構(gòu)圖
-北京總公司
---總公司人力資源部
---總公司財(cái)務(wù)部
---上海華東分公司
-----上海華東分公司人力資源部
-----上海華東分公司財(cái)務(wù)部
-----南京辦事處
-------南京辦事處人力資源部
-------南京辦事處財(cái)務(wù)部
-----杭州辦事處
-------杭州辦事處人力資源部
-------杭州辦事處財(cái)務(wù)部
職責(zé)
總公司人力資源部員工招聘培訓(xùn)管理
總公司財(cái)務(wù)部員工招聘培訓(xùn)管理
上海華東分公司人力資源部員工招聘培訓(xùn)管理
上海華東分公司財(cái)務(wù)部員工招聘培訓(xùn)管理
南京辦事處人力資源部員工招聘培訓(xùn)管理
南京辦事處財(cái)務(wù)部員工招聘培訓(xùn)管理
杭州辦事處人力資源部員工招聘培訓(xùn)管理
杭州辦事處財(cái)務(wù)部員工招聘培訓(xùn)管理