视频:https://www.bilibili.com/video/BV1Np4y1z7BU?p=1&vd_source=fc7fa697b97f292319c5b0cde4755484
代码:https://gitee.com/wangzai6/design_pattern.git

1.java设计模式7大原则

1.单一职责：

2.接口隔离原则

1.图解：

2.实现：

1.三个接口

2.B类实现1，2接口

3.D类实现1，3接口

4.A类通过使用Interface1，2 依赖使用B类，只会用到1，2，3方法

5.C类通过使用Interface1，3依赖使用D类，只会用到1，4，5方法

6.A类通过实例化B类使用B中的方法

7.C类通过实例化D类使用D中的方法

3.依赖倒转原则

1.原来使用

2.改进

4.里氏替换原则

5.开闭原则(ocp原则)

6.迪米特法则

7.合成复用原则

2.设计模式分类

1.创建型模式

1.单例模式

1.饿汉式：类加载就会导致该实例对象被创建

1.饿汉式（静态变量方式）

package com.hejiawang.pattern.singleton.demo1;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 10:54
 **/
//饿汉式：静态成员变量
public class Singleton {

//    1.私有构造方法
    private Singleton(){

    }
//    2.在奔雷中创建本类对象
    private static Singleton instance = new Singleton();

//    3.提供一个公共的访问方式，让外界获取改对象
    public static Singleton getInstance(){
        return instance;
    }
}

查看测试结果

2.饿汉式（静态代码块）

package com.hejiawang.pattern.singleton.demo2;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//饿汉式：静态代码块
public class Singleton {
//    私有构造方法
    private Singleton(){}
//    声明Singleton类型的变量
    private static Singleton instance; //null
//    在静态代码块中进行赋值
    static {
        instance = new Singleton();
    }

//    对外提供获取该类对象的方法
    public static Singleton getInstance(){
        return instance;
    }
}

查看测试结果

说明

2.懒汉式：类加载不会导致该实例对象被创建，而是首次使用该对象时才会创建

1.懒汉式（线程不安全）

如果2个线程同时进入判断 条件，则创建的实例不删单例

package com.hejiawang.pattern.singleton.demo3;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式
public class Singleton {
//    私有构造方法
    private Singleton(){}
//    声明Singleton类型的变量
    private static Singleton instance; //null

//    对外提供获取该类对象的方法
    public static Singleton getInstance(){
//        判断instance是否为null，如果为null，说明还没有创建爱你Singleton类的对象
//        如果没有，创建一个并返回，如果有直接返回
        if(instance == null){
//            线程1等待，线程2获取cpu的执行权，也会进入改判断里面，所以可能创建多个实例 
            instance = new Singleton();
        }
        return instance;
    }
}

2.懒汉式（线程安全）

在拿实例方法上面加上synchronized锁，线程即安全

package com.hejiawang.pattern.singleton.demo3;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式
public class Singleton {
//    私有构造方法
    private Singleton(){}
//    声明Singleton类型的变量
    private static Singleton instance; //null

//    对外提供获取该类对象的方法
    public static synchronized Singleton getInstance(){
//        判断instance是否为null，如果为null，说明还没有创建Singleton类的对象
//        如果没有，创建一个并返回，如果有直接返回
        if(instance == null){
            instance = new Singleton();
        }
        return instance;
    }
}

3.懒汉式（双重检查锁方式）

对于getInstance()方法来说，绝大部分都是读操作，读操作是线程安全的，所以没必要让每个线程必须持有锁才调用方法，我们需要调整加锁的时机，即双重检查锁模式

package com.hejiawang.pattern.singleton.demo4;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式:双重检查锁方式
public class Singleton {
//    私有构造方法
    private Singleton(){}
//    声明Singleton类型的变量
    private static Singleton instance; //null
//    对外提供获取该类对象的方法
    public static  Singleton getInstance(){
//        第一次判断，如果instance的值不为null，不需要抢占锁，直接返回对象
        if(instance == null){
            synchronized (Singleton.class){
//                第二次判断
                if (instance == null) {
                    instance = new Singleton();
                }
            }
        }
        return instance;
    }
}

4.使用volitale保证变量有序性和可见性

双重检查锁模式是一种非常好的单例实现模式，解决了单例，性能，线程安全问题，看上去完美无缺，其实存在许多问题，在多线程的情况下，可能出现空指针问题，出现问题的原因是JVM在实例化对象的时候会进行优化和指令重排序操作。要解决双重检查锁模式带来的空指针异常的问题，只需要使用volatile关键字，volatile关键字可以保证可见性和有序性

package com.hejiawang.pattern.singleton.demo4;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式:双重检查锁方式（使用volatile保证可见性和有序性）
public class Singleton {
//    私有构造方法
    private Singleton(){}
//    声明Singleton类型的变量
    private static volatile Singleton instance; //null
//    对外提供获取该类对象的方法
    public static  Singleton getInstance(){
//        第一次判断，如果instance的值不为null，不需要抢占锁，直接返回对象
        if(instance == null){
            synchronized (Singleton.class){
//                第二次判断
                if (instance == null) {
                    instance = new Singleton();
                }
            }
        }
        return instance;
    }
}

5.懒汉式方式（静态内部类方式）

第一次加载Singleton类时不会去初始化INSTANCE，只有第一次调用getinstance，虚拟机加载SingletonHolder并初始化INSTANCE，这样不仅确保线程安全，也能保证Singleton类的唯一性，这种方式保证了多线程下的安全，并且没有任何性能影响和空间浪费
静态内部类单例模式中实例有内部类创建，由于JVM在加载外部类的过程中，是不会加载静态内部类，只有内部类的属性/方法被调用时候才加载，并初始化其静态属性，静态属性由于被static修饰，保证只被实例化一次，并严格保证实例化顺序

package com.hejiawang.pattern.singleton.demo5;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式:静态内部类方式
public class Singleton {
//    私有构造方法
    private Singleton(){}
//    定义一个静态内部类
    private static class SingletonHolder{
//                在内部类中声明并初始化外部类的对象
        private static final Singleton INSTANCE = new Singleton();
    }
//    提供公共的访问方式
    public static Singleton getInstance(){
        return SingletonHolder.INSTANCE;
    }
}

3.枚举方式属于饿汉方式

使用枚举类实现单例模式是极利推荐的，因为枚举类型是线程安全的，并且只会加载一次

package com.hejiawang.pattern.singleton.demo6;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//枚举实现方式 属于饿汉方式
public enum Singleton {
    INSTANCE;
}

查看检查结果

4.通过序列化和反序列化可破坏单例模式及解决办法

反序列化破坏单例Demo

package com.hejiawang.pattern.singleton.demo7;
import com.hejiawang.pattern.singleton.demo7.Singleton;
import java.io.*;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:06
 **/
//测试使用反射破坏单例模式
public class Client {
    public static void main(String[] args) throws Exception {
//        writeObject2File();
        readObjectFromFile();
        readObjectFromFile();
    }
//     从文件中读取数据（对象）
    public static void readObjectFromFile() throws IOException, ClassNotFoundException {
//        1.创建爱你对象输入流对象
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("/Users/hejiawang/IdeaProjects/gitee/a.txt"));
//        2.读取对象
        Singleton instance = (Singleton) ois.readObject();
        System.out.println(instance);
        ois.close();
    }

//    向文件中写数据（对象）
    public static void writeObject2File() throws Exception {
//        1.获取Singleton对象
        Singleton instance = Singleton.getInstance();
//        2.创建对象输出流对象
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("/Users/hejiawang/IdeaProjects/gitee/a.txt"));
//        3.写对象
        oos.writeObject(instance);
        oos.close();
    }
}

检测结果：
两个地址不一致，两次反序列化的结果不是同一个地址

解决办法：
对象加上readResolve（）方法返回对象即可，

public class Singleton implements Serializable {
//    私有构造方法
    private Singleton(){}
//    定义一个静态内部类
    private static class SingletonHolder{
//                在内部类中声明并初始化外部类的对象
        private static final Singleton INSTANCE = new Singleton();
    }
//    提供公共的访问方式
    public static Singleton getInstance(){
        return SingletonHolder.INSTANCE;
    }
//  当进行反序列化时，自动调用改方法，将该方法的返回值直接返回
    public  Object readResolve(){
        return SingletonHolder.INSTANCE;
    }
}

重新序列化到文件中，并且重新执行读取对象打印对象内存地址，如下任然是单例

源码中会直接返回readResolve（）方法的结果

5.通过反射破坏单例模式及解决办法

反射破坏单例Demo

package com.hejiawang.pattern.singleton.demo8;

import java.io.*;
import java.lang.reflect.Constructor;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:06
 **/
//测试使用反射破坏单例模式
public class Client {
    public static void main(String[] args) throws Exception {
//    1.获取Singleton的字节码对象
        Class clazz = Singleton.class;
//    2.获取无参构造方法对象
        Constructor cons = clazz.getDeclaredConstructor();
//    3.取消访问检查
        cons.setAccessible(true);
//    4.创建Singleton对象
        Singleton s1 = (Singleton) cons.newInstance();
        Singleton s2 = (Singleton) cons.newInstance();
        System.out.println(s1 == s2); //如果返回的是true，说明并没有破坏单例模式，如果是false，说明破坏了单例模式
    }
}

结果

解决办法
在反射使用的无参构造方法中加入static flag 判断是第几次调无参构造方法。

package com.hejiawang.pattern.singleton.demo8;

import java.io.Serializable;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式:静态内部类方式
public class Singleton implements Serializable {
    private static boolean flag = false;
//    私有构造方法
    private Singleton(){
//        判断flag的值是否是true，如果是true，说明第一下访问，直接抛一个异常，如果是false的话，说明第一次访问，正常创建
        if (flag){
            throw new RuntimeException("不能创建多个对象");
        }
//        将flag的值设置为true
        flag = true;
    }
//    定义一个静态内部类
    private static class SingletonHolder{
//                在内部类中声明并初始化外部类的对象
        private static final Singleton INSTANCE = new Singleton();
    }
//    提供公共的访问方式
    public static Singleton getInstance(){
        return SingletonHolder.INSTANCE;
    }
}

第二次利用反射初始化对象抛出运行时异常

6.JDK中单例设计模式的Demo

jdk中的源代码，饿汉式单例

RuntimeDemo

package com.hejiawang.pattern.singleton.demo9;

import jdk.internal.util.xml.impl.Input;
import org.omg.SendingContext.RunTime;

import java.io.IOException;
import java.io.InputStream;
import java.io.Serializable;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 11:03
 **/
//懒汉式:静态内部类方式
public class RuntimeDemo implements Serializable {
    public static void main(String[] args) throws IOException {
//        获取Runtime类的对象
        Runtime runtime = Runtime.getRuntime();
//        调用runtime的方法exec,参数是一个命令
        Process process = runtime.exec("ifconfig");
//         调用process对象的获取输入流的方法
        InputStream is = process.getInputStream();
        byte[] arr = new byte[1024 * 1024 * 100];
//        读取数据
        int len = is.read(arr);  //返回读取到的字节的个数
//          将字节数组转换为字符串输出到控制台
        System.out.println(new String(arr,0,len,"GBK"));
    }
}

即可在输出台看到命令打印的信息

2.工厂模式

工厂模式最大优点：解耦

1.简单工厂模式

Coffee

package com.hejiawang.pattern.factory.simple_factiory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 16:59
 **/
public abstract class Coffee {
    public abstract String getName();
//    加糖
    public void addsugar(){
        System.out.println("加糖");
    }
//  加奶
    public void addMilk(){
        System.out.println("加奶");
    }
}

LatteCoffee

package com.hejiawang.pattern.factory.simple_factiory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:06
 **/
public class LatteCoffee extends Coffee {
    @Override
    public String getName() {
        return "拿铁咖啡";
    }
}

AmericanCoffee

package com.hejiawang.pattern.factory.simple_factiory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:05
 **/
public class AmericanCoffee extends Coffee {
    @Override
    public String getName() {
        return "美式咖啡";
    }
}

SimpleCoffeeFactory

package com.hejiawang.pattern.factory.simple_factiory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:20
 **/
public class SimpleCoffeeFactory {
    public Coffee createCoffee(String type){
        Coffee coffee = null;
        if("american".equals(type)){
            coffee = new AmericanCoffee();
        } else if ("latte".equals(type)){
            coffee = new LatteCoffee();
        } else{
            throw new RuntimeException("对不起，您所点的咖啡没有");
        }
        return coffee;
    }
}

CoffeeStore

package com.hejiawang.pattern.factory.simple_factiory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:06
 **/
public class CoffeeStore {
    public Coffee orderCoffee(String type){
    SimpleCoffeeFactory factory = new SimpleCoffeeFactory();
//    调用生产咖啡的方法
        Coffee coffee = factory.createCoffee(type);
//        加配料
        coffee.addMilk();
        coffee.addsugar();
        return coffee;
    }
}

2.工厂方法模式

Coffee

package com.hejiawang.pattern.factory.factory_method;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 16:59
 **/
public abstract class Coffee {
    public abstract String getName();
//    加糖
    public void addsugar(){
        System.out.println("加糖");
    }
//  加奶
    public void addMilk(){
        System.out.println("加奶");
    }
}

LatteCoffee

package com.hejiawang.pattern.factory.factory_method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:06
 **/
public class LatteCoffee extends Coffee {
    @Override
    public String getName() {
        return "拿铁咖啡";
    }
}

AmericanCoffee

package com.hejiawang.pattern.factory.factory_method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:05
 **/
public class AmericanCoffee extends Coffee {
    @Override
    public String getName() {
        return "美式咖啡";
    }
}

CoffeeFactory

package com.hejiawang.pattern.factory.factory_method;
//抽象工厂
public interface CoffeeFactory {

//    创建咖啡对象的方法
    Coffee createCoffee();
}

LatteCoffeeFactory

package com.hejiawang.pattern.factory.factory_method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:48
 **/
public class LatteCoffeeFactory implements CoffeeFactory {
    public Coffee createCoffee() {
        return new LatteCoffee();
    }
}

AmericanCoffeeFactory

package com.hejiawang.pattern.factory.factory_method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:44
 **/
public class AmericanCoffeeFactory implements CoffeeFactory{

    public Coffee createCoffee() {
        return new AmericanCoffee();
    }
}

CoffeeStore

package com.hejiawang.pattern.factory.factory_method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:06
 **/
public class CoffeeStore {
    private CoffeeFactory factory;

    public void setFactory(CoffeeFactory factory){
        this.factory = factory;
    }

    public Coffee orderCoffee(){
        Coffee coffee = factory.createCoffee();
//      加配料
        coffee.addsugar();
        coffee.addMilk();
        return coffee;
    }
}

Client

package com.hejiawang.pattern.factory.factory_method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:25
 **/
public class Client {
    public static void main(String[] args) {
//        创建咖啡对象
        CoffeeStore store = new CoffeeStore();
//        创建对象
//        CoffeeFactory factory = new AmericanCoffeeFactory();
        CoffeeFactory factory = new LatteCoffeeFactory();

        store.setFactory(factory);
        Coffee coffee = store.orderCoffee();
        System.out.println(coffee.getName());
    }
}

3.抽象工厂模式

Coffee

package com.hejiawang.pattern.factory.abstract_factory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 16:59
 **/
public abstract class Coffee {
    public abstract String getName();

//    加糖
    public void addsugar(){
        System.out.println("加糖");
    }
//  加奶
    public void addMilk(){
        System.out.println("加奶");
    }
}

LatteCoffee

package com.hejiawang.pattern.factory.abstract_factory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:06
 **/
public class LatteCoffee extends Coffee {
    @Override
    public String getName() {
        return "拿铁咖啡";
    }
}

AmericanCoffee

package com.hejiawang.pattern.factory.abstract_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:05
 **/
public class AmericanCoffee extends Coffee {
    @Override
    public String getName() {
        return "美式咖啡";
    }
}

Dessert

package com.hejiawang.pattern.factory.abstract_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:10
 **/
public abstract class Dessert {
    public abstract void show ();
}

MatchMousse

package com.hejiawang.pattern.factory.abstract_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:12
 **/
public class MatchMousse extends Dessert {
    @Override
    public void show() {
        System.out.println("抹茶慕斯");
    }
}

Trimisu

package com.hejiawang.pattern.factory.abstract_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:11
 **/
public class Trimisu extends Dessert{
    @Override
    public void show(){
        System.out.println("提拉米苏");
    }
}

DessertFactory

package com.hejiawang.pattern.factory.abstract_factory;

public interface DessertFactory {
//    生产咖啡的功能
    Coffee createCoffee();
//      生产甜品的功能
    Dessert createDessert();
}

ItalyDessertFactory

package com.hejiawang.pattern.factory.abstract_factory;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:17
 **/
public class ItalyDessertFactory implements DessertFactory{
    public Coffee createCoffee() {
        return new LatteCoffee();
    }

    public Dessert createDessert() {
        return new Trimisu();
    }
}

AmericanDessertFactory

package com.hejiawang.pattern.factory.abstract_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:14
 **/
public class AmericanDessertFactory implements DessertFactory {
    public Coffee createCoffee() {
        return new AmericanCoffee();
    }
    public Dessert createDessert() {
        return new MatchMousse();
    }
}

Client

package com.hejiawang.pattern.factory.abstract_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:17
 **/
public class Client {
    public static void main(String[] args) {
//        ItalyDessertFactory factory = new ItalyDessertFactory();
        AmericanDessertFactory factory = new AmericanDessertFactory();
        Coffee coffee = factory.createCoffee();
        Dessert dessert = factory.createDessert();
        System.out.println(coffee.getName());
        dessert.show();
    }
}

4.模式扩展（配置文件+工厂模式）

1.添加配置文件

american=com.hejiawang.pattern.factory.config_factory.AmericanCoffee
latte=com.hejiawang.pattern.factory.config_factory.LatteCoffee

2.代码演示

Coffee

package com.hejiawang.pattern.factory.config_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 16:59
 **/
public abstract class Coffee {
    public abstract String getName();
//    加糖
    public void addsugar(){
        System.out.println("加糖");
    }
//  加奶
    public void addMilk(){
        System.out.println("加奶");
    }
}

LatteCoffee

package com.hejiawang.pattern.factory.config_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:06
 **/
public class LatteCoffee extends Coffee {
    @Override
    public String getName() {
        return "拿铁咖啡";
    }
}

AmericanCoffee

package com.hejiawang.pattern.factory.config_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-11 17:05
 **/
public class AmericanCoffee extends Coffee {
    @Override
    public String getName() {
        return "美式咖啡";
    }
}

CoffeeFactory加载配置文件，根据入参通过反射机制加载初始化需要创建的类

package com.hejiawang.pattern.factory.config_factory;

import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Properties;
import java.util.Set;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:36
 **/
public class CoffeeFactory {
//    加载配置文件，获取配置文件中配置的全类名，并创建该类的对象进行存储
//    1.定义容器对象存储咖啡对象
     private static HashMap<String,Coffee> map = new HashMap<String, Coffee>();

//     2.加载配置文件
    static{
//        2.1创建Properties对象
    Properties properties = new Properties();
//      2.2调用p对象中deload方法进行配置文件的加载
    InputStream is = CoffeeFactory.class.getClassLoader().getResourceAsStream("bean.properties");
    try {
        properties.load(is);
        Set<Object> keys = properties.keySet();
        for (Object key: keys){
            String className = properties.getProperty((String) key);
//            通过反射技术创建对象
            Class clazz = Class.forName(className);
            Coffee coffee = (Coffee) clazz.newInstance();
            //将名称和对象存储到容器中
            map.put((String)key,coffee);
        }
    } catch (Exception e) {
        e.printStackTrace();
    }

}
    public static Coffee createCoffee(String name){
        return map.get(name);
    }
}

Client

package com.hejiawang.pattern.factory.config_factory;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 10:47
 **/
public class Client {
    public static void main(String[] args) {
        Coffee american = CoffeeFactory.createCoffee("american");
        System.out.println(american.getName());
        System.out.println("============");
        Coffee latte = CoffeeFactory.createCoffee("latte");
        System.out.println(latte.getName());
    }
}

检测结果

5.jdk源码解析-Collection.iterator方法

3.原型模式

1.简单的原型模式演示

浅克隆和深克隆

原型模式Demo
Realizetype

package com.hejiawang.pattern.prototype.demo;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-13 14:01
 **/
public class Realizetype implements Cloneable{
    public Realizetype(){
        System.out.println("具体的原型对象创建完成！");
    }
    @Override
    protected Realizetype clone() throws CloneNotSupportedException {
        System.out.println("具体原型复制成功！");
        return (Realizetype) super.clone();
    }
}

Client

package com.hejiawang.pattern.prototype.demo;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:18
 **/
public class Client {
    public static void main(String[] args) throws CloneNotSupportedException {
//        创建一个原型类对象
        Realizetype realizetype = new Realizetype();
//        调用Realizetype类中的clone方法进行对象的克隆
        Realizetype clone =realizetype.clone();
        System.out.println("原型对象和克隆出来的是否是同一个对象？"+(realizetype == clone));
    }
}

打印结果

2.原型对象使用Demo（浅克隆）

Citation

package com.hejiawang.pattern.prototype.test;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:28
 **/
public class Citation implements Cloneable {
//    三好学生的姓名
    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    protected void show() {
        System.out.println(name+"同学，被评为三好学生，特发此状，以兹鼓励");
    }

    @Override
    protected Citation clone() throws CloneNotSupportedException {
        return (Citation) super.clone();
    }
}

CitationTest

package com.hejiawang.pattern.prototype.test;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:32
 **/
public class CitationTest {
    public static void main(String[] args) throws CloneNotSupportedException {
//        1.创建原型对象
        Citation citation = new Citation();
//        2.克隆奖状对象
        Citation citationClone = citation.clone();
        citation.setName("飞鸽");
        citationClone.setName("肥宅子");
//        3.调用show方法展示
        citation.show();
        citationClone.show();
    }
}

打印结果

3.原型对象使用Demo（浅克隆）

浅克隆：创建新的对象，新对象的属性和原来对象完全相同，对于非基本类型属性，仍指向原有属性所只想的对象的地址
Student

package com.hejiawang.pattern.prototype.test;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:38
 **/
public class Student {
//    学生的姓名
    private String name;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                '}';
    }
}

Citation

package com.hejiawang.pattern.prototype.test;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:28
 **/
public class Citation implements Cloneable {
    private Student student;

    protected void show() {
        System.out.println(student.getName()+"同学，被评为三好学生，特发此状，以兹鼓励");
    }

    @Override
    protected Citation clone() throws CloneNotSupportedException {
        return (Citation) super.clone();
    }

    public Student getStudent() {
        return student;
    }

    public void setStudent(Student student) {
        this.student = student;
    }
}

CitationTest

package com.hejiawang.pattern.prototype.test;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:32
 **/
public class CitationTest {
    public static void main(String[] args) throws CloneNotSupportedException {
//        1.创建原型对象
        Citation citation = new Citation();
//        创建学生对象
        Student student = new Student();
        student.setName("飞鸽");
        citation.setStudent(student);
//        2.克隆奖状对象
        Citation citationClone = citation.clone();
        citationClone.getStudent().setName("肥宅子");
//        3.调用show方法展示
        citation.show();
        citationClone.show();
    }
}

打印结果

4.使用序列化实现（深克隆）

注意序列化对象要实现Serializable接口
Student

package com.hejiawang.pattern.prototype.test1;

import java.io.Serializable;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:38
 **/
public class Student implements Serializable {
//    学生的姓名
    private String name;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                '}';
    }
}

Citation

package com.hejiawang.pattern.prototype.test1;

import java.io.Serializable;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:28
 **/
public class Citation implements Cloneable, Serializable {
    private Student student;

    protected void show() {
        System.out.println(student.getName()+"同学，被评为三好学生，特发此状，以兹鼓励");
    }
    @Override
    protected Citation clone() throws CloneNotSupportedException {
        return (Citation) super.clone();
    }
    public Student getStudent() {
        return student;
    }

    public void setStudent(Student student) {
        this.student = student;
    }
}

CitationTest

package com.hejiawang.pattern.prototype.test1;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 14:32
 **/
public class CitationTest {
    public static void main(String[] args) throws Exception {
//        1.创建原型对象
        Citation citation = new Citation();
//        创建学生对象
        Student student = new Student();
        student.setName("飞鸽");
        citation.setStudent(student);
//        创建对象输出流对象
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("/Users/hejiawang/IdeaProjects/gitee/b.txt"));
//        写对象
        oos.writeObject(citation);
//        释放资源
        oos.close();
//        创建对象输入流对象
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("/Users/hejiawang/IdeaProjects/gitee/b.txt"));
//        读取对象
        Citation citation1 = (Citation) ois.readObject();
//        释放资源
        ois.close();
        Student student1 = citation1.getStudent();
        student1.setName("肥宅子");

        citation.show();
        citation1.show();
    }
}

打印结果

4.建造者模式

1.创建自行车案例

Bike

package com.hejiawang.pattern.factory.builder.demo1;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 16:30
 **/
public class Bike {
    private String frame;//车架
    private String seat;//车座
    public String getFrame() {
        return frame;
    }
    public void setFrame(String frame) {
        this.frame = frame;
    }

    public String getSeat() {
        return seat;
    }
    public void setSeat(String seat) {
        this.seat = seat;
    }
}

Builder

package com.hejiawang.pattern.factory.builder.demo1;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 16:31
 **/
public abstract class Builder {
//    声明Bike类型的变量,并进行赋值
    protected Bike bike = new Bike();
    public abstract void buildFrame();
    public abstract void buildSeat();
    public abstract Bike createBike();
}

MobileBuilder

package com.hejiawang.pattern.factory.builder.demo1;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 16:34
 **/
public class MobileBuilder extends Builder{
    @Override
    public void buildFrame() {
        bike.setFrame("碳纤维车架");
    }
    @Override
    public void buildSeat() {
        bike.setSeat("真皮座驾");
    }
    @Override
    public Bike createBike() {
        return bike;
    }
}

OfoBuilder

package com.hejiawang.pattern.factory.builder.demo1;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 16:36
 **/
public class OfoBuilder extends Builder{
    @Override
    public void buildFrame() {
        bike.setFrame("铝合金车架");
    }

    @Override
    public void buildSeat() {
        bike.setSeat("橡胶车座");
    }

    @Override
    public Bike createBike() {
        return bike;
    }
}

Director

package com.hejiawang.pattern.factory.builder.demo1;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 16:37
 **/
public class Director {
//    声明builder类型的变量
    private Builder builder;

    public Director(Builder builder) {
        this.builder = builder;
    }
//    组装自行车的功能
    public Bike construct(){
        builder.buildFrame();
        builder.buildSeat();
        return builder.createBike();
    }
}

Client

package com.hejiawang.pattern.factory.builder.demo1;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 16:41
 **/
public class Client {
    public static void main(String[] args) {
//        创建指挥者对象
        Director director = new Director(new MobileBuilder());
//        让指挥者指挥组装自行车
        Bike bike = director.construct();
        System.out.println(bike.getFrame());
        System.out.println(bike.getSeat());
    }
}

打印结果

优化建造者模式

优缺点

使用场景

2.模式扩展

Phone对象类

package com.hejiawang.pattern.factory.builder.demo2;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-17 17:27
 **/
public class Phone {
    private String cpu;
    private String screen;
    private String memory;
    private String mainboard;
//    私有构造方法
    private Phone(Builder builder){
        this.cpu = builder.cpu;
        this.screen = builder.screen;
        this.memory = builder.memory;
        this.mainboard = builder.mainboard;
    }
    public static final class Builder {
        private String cpu;
        private String screen;
        private String memory;
        private String mainboard;

        public Builder cpu(String cpu){
            this.cpu = cpu;
            return this;
        }
        public Builder screen(String screen){
            this.screen = screen;
            return this;
        }
        public Builder memory(String memory){
            this.memory = memory;
            return this;
        }
        public Builder mainboard(String mainboard){
            this.mainboard = mainboard;
            return this;
        }
//        使用构建者创建Phone对象
        public Phone  build(){
            return new Phone(this);
        }
    }

    @Override
    public String toString() {
        return "Phone{" +
                "cpu='" + cpu + '\'' +
                ", screen='" + screen + '\'' +
                ", memory='" + memory + '\'' +
                ", mainboard='" + mainboard + '\'' +
                '}';
    }
}

Client测试类

package com.hejiawang.pattern.factory.builder.demo2;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 20:45
 **/
public class Client {
    public static void main(String[] args) {
        Phone phone = new Phone.Builder()
                .cpu("m2")
                .screen("小米屏幕")
                .memory("金士顿")
                .mainboard("华硕")
                .build();
        System.out.println(phone.toString());
    }
}

打印结果

5.创建模式对比

2.结构型模式

1.代理模式

1.静态代理

SellTickets

package com.hejiawang.pattern.proxy.static_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:17
 **/
public interface SellTickets {
    void sell();
}

TrainStation

package com.hejiawang.pattern.proxy.static_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:18
 **/
public class TrainStation implements SellTickets {
    public void sell() {
        System.out.println("火车站卖票");
    }
}

ProxyPoint

package com.hejiawang.pattern.proxy.static_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:21
 **/
//代售点类
public class ProxyPoint implements SellTickets {
//    声明火车站类对象
    private TrainStation trainStation = new TrainStation();
    public void sell() {
        System.out.println("代售点收取一些服务费用");
        trainStation.sell();
    }
}

Client

package com.hejiawang.pattern.proxy.static_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:23
 **/
public class Client {
    public static void main(String[] args) {
//        创建代售点类对象
        ProxyPoint proxyPoint = new ProxyPoint();
//         调用方法进行买票
        proxyPoint.sell();
    }
}

打印结果

2.动态代理

1.JDK动态代理

SellTickets

package com.hejiawang.pattern.proxy.jdk_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:17
 **/
public interface SellTickets {
    void sell();
}

TrainStation

package com.hejiawang.pattern.proxy.jdk_proxy;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:18
 **/
public class TrainStation implements SellTickets {
    public void sell() {
        System.out.println("火车站卖票");
    }
}

ProxyFactory

package com.hejiawang.pattern.proxy.jdk_proxy;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.sql.SQLOutput;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:29
 **/
//获取代理对象的工厂类
//代理类也实现了对应的接口
public class ProxyFactory {
//    声明目标对象
    private TrainStation station = new TrainStation();

//  获取代理对象的方法
    public SellTickets getProxyObject() {
//        返回代理对象即可
        /*
            ClassLoader loader ： 类加载器，用于加载代理类，可以通过目标对象获取类加载器
            Class<?>[] interfaces ：  代理类实现的接口的字节码对象
            InvocationHandler h ： 代理对象的调用处理程序
        */
        SellTickets proxyInstance = (SellTickets) Proxy.newProxyInstance(station.getClass().getClassLoader(), station.getClass().getInterfaces(), new InvocationHandler() {
            /*
            * Object proxy ： 代理对象和proxyInstance对象是同一个对象，在invoke方法中基本不用
            * Method method ： 对接口中的方法进行封装的method对象
            * Object[] args ： 调用方法的实际参数
            *
            * 返回值就是方法的返回值。
            */
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
//                System.out.println("invoke方法执行了");
                System.out.println("代售点收取一定的服务费用（jdk动态代理）");
//              执行目标对象的方法
                Object obj = method.invoke(station, args);
                return obj;
            }
        });
        return proxyInstance;
    }
}

Client

package com.hejiawang.pattern.proxy.jdk_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-01 10:49
 **/
public class Client {
    public static void main(String[] args) {
//        获取代理对象
//        1.创建代理工厂对象
        ProxyFactory factory = new ProxyFactory();
//        2.使用factory对象的方法获取代理对象
        SellTickets proxyObject = factory.getProxyObject();
//        3.调用卖电脑的方法
        proxyObject.sell();
    }
}

打印结果

2.动态代理原理分析

通过arthas来查看生成的代理类
加入死循环让进程不结束

package com.hejiawang.pattern.proxy.jdk_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-01 10:49
 **/
public class Client {
    public static void main(String[] args) {
//        获取代理对象
//        1.创建代理工厂对象
        ProxyFactory factory = new ProxyFactory();
//        2.使用factory对象的方法获取代理对象
        SellTickets proxyObject = factory.getProxyObject();
//        3.调用卖票的方法
        proxyObject.sell();
        System.out.println(proxyObject.getClass());
//      让程序一直运行
        while(true){}

    }
}

启动arthas,选择对应在跑的进程使用jad将答应的代理类类名输入jad反编译即可获得在jvm中运行的代理类

代理对象反编译后的源码

/*
 * Decompiled with CFR.
 *
 * Could not load the following classes:
 *  com.hejiawang.pattern.proxy.jdk_proxy.SellTickets
 */
package com.sun.proxy;

import com.hejiawang.pattern.proxy.jdk_proxy.SellTickets;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.lang.reflect.UndeclaredThrowableException;

public final class $Proxy0 extends Proxy
implements SellTickets {
    private static Method m1;
    private static Method m2;
    private static Method m3;
    private static Method m0;

    public $Proxy0(InvocationHandler invocationHandler) {
        super(invocationHandler);
    }

    public final boolean equals(Object object) {
        try {
            return (Boolean)this.h.invoke(this, m1, new Object[]{object});
        }
        catch (Error | RuntimeException throwable) {
            throw throwable;
        }
        catch (Throwable throwable) {
            throw new UndeclaredThrowableException(throwable);
        }
    }

    public final String toString() {
        try {
            return (String)this.h.invoke(this, m2, null);
        }
        catch (Error | RuntimeException throwable) {
            throw throwable;
        }
        catch (Throwable throwable) {
            throw new UndeclaredThrowableException(throwable);
        }
    }

    public final void sell() {
        try {
            this.h.invoke(this, m3, null);
            return;
        }
        catch (Error | RuntimeException throwable) {
            throw throwable;
        }
        catch (Throwable throwable) {
            throw new UndeclaredThrowableException(throwable);
        }
    }

    public final int hashCode() {
        try {
            return (Integer)this.h.invoke(this, m0, null);
        }
        catch (Error | RuntimeException throwable) {
            throw throwable;
        }
        catch (Throwable throwable) {
            throw new UndeclaredThrowableException(throwable);
        }
    }

    static {
        try {
            m1 = Class.forName("java.lang.Object").getMethod("equals", Class.forName("java.lang.Object"));
            m2 = Class.forName("java.lang.Object").getMethod("toString", new Class[0]);
            m3 = Class.forName("com.hejiawang.pattern.proxy.jdk_proxy.SellTickets").getMethod("sell", new Class[0]);
            m0 = Class.forName("java.lang.Object").getMethod("hashCode", new Class[0]);
            return;
        }
        catch (NoSuchMethodException noSuchMethodException) {
            throw new NoSuchMethodError(noSuchMethodException.getMessage());
        }
        catch (ClassNotFoundException classNotFoundException) {
            throw new NoClassDefFoundError(classNotFoundException.getMessage());
        }
    }
}

3.CGLIB动态代理

TrainStation

package com.hejiawang.pattern.proxy.cglib_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-06-30 21:18
 **/
public class TrainStation {
    public void sell() {
        System.out.println("火车站卖票");
    }
}

ProxyFactory

package com.hejiawang.pattern.proxy.cglib_proxy;

import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;
import java.lang.reflect.Method;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-02 16:50
 **/
//  代理对象工厂，用来获取代理对象
public class ProxyFactory implements MethodInterceptor {
//    声明火车站对象
    private TrainStation station = new TrainStation();
    public TrainStation getProxyObject() {
//        创建Enhancer对象，类似JDK代理中的Proxy类
        Enhancer enhancer = new Enhancer();
//        设置父类的字节码对象
        enhancer.setSuperclass(TrainStation.class);
        //        设置回调函数
        enhancer.setCallback(this);
//    创建代理对象
        TrainStation proxyObject = (TrainStation)enhancer.create();
        return proxyObject;
    }
    public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
//        System.out.println("方法执行了");
        System.out.println("代售点收取一定的服务费用(CGLib代理)");
//        要调用目标对象的方法
        Object obj = method.invoke(station, objects);
        return obj;
    }
}

Client

package com.hejiawang.pattern.proxy.cglib_proxy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-02 17:07
 **/
public class Client {
    public static void main(String[] args) {
//        创建代理工厂对象
        ProxyFactory factory = new ProxyFactory();
//        获取代理对象
        TrainStation proxyObject= factory.getProxyObject();
//        调用代理对象中的sell方法卖票
        proxyObject.sell();

    }
}

打印结果

4.代理方式比较

2.适配器模式

1.类适配器模式

SDCard

package com.hejiawang.pattern.adapter.class_adapter;

public interface SDCard {
//  从SD卡中读取数据
    String readSD();
//    往SD卡中写数据
    void writeSD(String msg);
}

SDCardImpl

package com.hejiawang.pattern.adapter.class_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:22
 **/
public class SDCardImpl implements SDCard {
    public String readSD() {
        String msg = "SDCard read msg : hello world SD";
        return msg;
    }

    public void writeSD(String msg) {
        System.out.println("SDCard write msg :" + msg);
    }
}

TFCard

package com.hejiawang.pattern.adapter.class_adapter;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:17
 **/
public interface TFCard{
//    从TF卡中读取数据
    String readTF();
//    往TF卡中写数据
    void writeTF(String msg);
}

TFCardImpl

package com.hejiawang.pattern.adapter.class_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:19
 **/
public class TFCardImpl implements TFCard {
    public String readTF() {
        String msg = "TFCard read msg : hello world TFcard";
        return msg;
    }

    public void writeTF(String msg) {
        System.out.println("TFCard write msg :" + msg);
    }
}

Computer

package com.hejiawang.pattern.adapter.class_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:23
 **/
//计算器类
public class Computer  {
//    从SD卡中读取数据
    public String readSD(SDCard sdCard){
        if(sdCard == null){
            throw new NullPointerException("sdCard is not null");
        }
        return sdCard.readSD();
    }
}

SDAdapterTF

package com.hejiawang.pattern.adapter.class_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:28
 **/
public class SDAdapterTF extends TFCardImpl implements SDCard {
    public String readSD() {
        System.out.println("adapter read tf card");
        return readTF();
    }

    public void writeSD(String msg) {
        System.out.println("adapter write tf card");
        writeTF(msg);
    }
}

Client

package com.hejiawang.pattern.adapter.class_adapter;

import com.sun.scenario.effect.impl.sw.sse.SSEBlend_SRC_OUTPeer;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:25
 **/
public class Client {
    public static void main(String[] args) {
//        创建计算机对象
        Computer computer = new Computer();
//        读取SD卡中的数据
        String msg = computer.readSD(new SDCardImpl());
        System.out.println(msg);
        System.out.println("=================");
//        使用该电脑读取TF卡中的数据
//        定义适配器类
        String msg1 = computer.readSD(new SDAdapterTF());
        System.out.println(msg1);
    }
}

打印结果

2.对象适配器模式

SDCard

package com.hejiawang.pattern.adapter.object_adapter;

public interface SDCard {
//  从SD卡中读取数据
    String readSD();
//    往SD卡中写数据
    void writeSD(String msg);
}

SDCardImpl

package com.hejiawang.pattern.adapter.object_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:22
 **/
public class SDCardImpl implements SDCard {
    public String readSD() {
        String msg = "SDCard read msg : hello world SD";
        return msg;
    }

    public void writeSD(String msg) {
        System.out.println("SDCard write msg :" + msg);
    }
}

TFCard

package com.hejiawang.pattern.adapter.object_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:17
 **/
public interface TFCard{
//    从TF卡中读取数据
    String readTF();
//    往TF卡中写数据
    void writeTF(String msg);
}

TFCardImpl

package com.hejiawang.pattern.adapter.object_adapter;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:19
 **/
public class TFCardImpl implements TFCard {
    public String readTF() {
        String msg = "TFCard read msg : hello world TFcard";
        return msg;
    }

    public void writeTF(String msg) {
        System.out.println("TFCard write msg :" + msg);
    }
}

Computer

package com.hejiawang.pattern.adapter.object_adapter;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:23
 **/
//计算器类
public class Computer  {
//    从SD卡中读取数据
    public String readSD(SDCard sdCard){
        if(sdCard == null){
            throw new NullPointerException("sdCard is not null");
        }
        return sdCard.readSD();
    }
}

SDAdapterTF

package com.hejiawang.pattern.adapter.object_adapter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:28
 **/
public class SDAdapterTF implements SDCard {
//    声明适配者类
    private TFCard tfCard;

    public SDAdapterTF(TFCard tfCard) {
        this.tfCard = tfCard;
    }

    public String readSD() {
        System.out.println("adapter read tf card");
        return tfCard.readTF();
    }

    public void writeSD(String msg) {
        System.out.println("adapter write tf card");
        tfCard.writeTF(msg);
    }
}

Client

package com.hejiawang.pattern.adapter.object_adapter;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 09:25
 **/
public class Client {
    public static void main(String[] args) {
//        创建计算机对象
        Computer computer = new Computer();
//        读取SD卡中的数据
        String msg = computer.readSD(new SDCardImpl());
        System.out.println(msg);
        System.out.println("=================");
//        使用该电脑读取TF卡中的数据
//        创建适配器对象
        SDAdapterTF sdAdapterTF =  new SDAdapterTF(new TFCardImpl());
//        定义适配器类
        String msg1 = computer.readSD(sdAdapterTF);
        System.out.println(msg1);
    }
}

打印结果

3.jdk源码解析

3.装饰者模式

1.案例

FastFood 快餐类（抽象构建角色）

package com.hejiawang.pattern.decorator;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 10:10
 **/
//快餐类（抽象构建角色）
public abstract class FastFood  {
    private float price;//价格
    private String desc; //描述
    public FastFood(float price, String desc) {
        this.price = price;
        this.desc = desc;
    }
    public String getDesc() {
        return desc;
    }
    public void setDesc(String desc) {
        this.desc = desc;
    }
    public float getPrice() {
        return price;
    }
    public void setPrice(float price) {
        this.price = price;
    }
    public abstract float cost();
}

FriedNoodles 炒面（具体构建角色）

package com.hejiawang.pattern.decorator;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 10:15
 **/
//炒面（具体构建角色）
public class FriedNoodles extends FastFood{
    public FriedNoodles() {
        super(12,"炒面");
    }
    @Override
    public float cost(){
        return getPrice();
    }
}

FriedRice 炒饭（具体构建角色）

package com.hejiawang.pattern.decorator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 10:13
 **/
// 炒饭（具体构建角色）
public class FriedRice extends FastFood{
    public FriedRice() {
        super(10,"炒饭");
    }
    @Override
    public float cost(){
        return getPrice();
    }
}

Garnish 装饰者（抽象装饰者角色）

package com.hejiawang.pattern.decorator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 10:16
 **/
// 装饰者（抽象装饰者角色）
public abstract class Garnish extends FastFood{
    //    声明快餐类的变量
    private FastFood fastFood;

    public Garnish( FastFood fastFood,float price, String desc) {
        super(price, desc);
        this.fastFood = fastFood;
    }
    public FastFood getFastFood() {
        return fastFood;
    }
    public void setFastFood(FastFood fastFood) {
        this.fastFood = fastFood;
    }
}

Egg 鸡蛋类（具体的装饰者角色）

package com.hejiawang.pattern.decorator;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 11:14
 **/
// 鸡蛋类（具体的装饰者角色）
public class Egg extends Garnish{
    public Egg(FastFood fastFood) {
        super(fastFood,1,"鸡蛋");
    }
    @Override
    public float cost(){
//        计算价格
        return getPrice() + getFastFood().cost();
    }
    @Override
    public String getDesc() {
        return super.getDesc()+getFastFood().getDesc();
    }
}

Bacon 培根类（具体的装饰者角色）

package com.hejiawang.pattern.decorator;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 11:14
 **/
// 培根类（具体的装饰者角色）
public class Bacon extends Garnish{
    public Bacon(FastFood fastFood) {
        super(fastFood,2,"培根");
    }
    @Override
    public float cost(){
//        计算价格
        return getPrice() + getFastFood().cost();
    }
    @Override
    public String getDesc() {
        return super.getDesc()+getFastFood().getDesc();
    }
}

Client

package com.hejiawang.pattern.decorator;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 15:47
 **/
public class Client {
    public static void main(String[] args) {
//        点一份炒饭
        FastFood food = new FriedRice();
        System.out.println(food.getDesc() + "  " + food.cost() + "元");
        System.out.println("==============");
//        在上面的炒饭中加一个鸡蛋
        food = new Egg(food);
        System.out.println(food.getDesc() + "  " + food.cost() + "元");
        System.out.println("==============");
//        再加一个鸡蛋
        food = new Egg(food);
        System.out.println(food.getDesc() + "  " + food.cost() + "元");
        System.out.println("==============");
        food = new Bacon(food);
        System.out.println(food.getDesc() + "  " + food.cost() + "元");
    }
}

打印结果

2.jdk中的使用

3.代理和装饰的区别

4.桥接模式

VideoFile 视频文件（实现化角色）

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 16:43
 **/
//视频文件（实现化角色）
public interface VideoFile{

//    解码功能
    void decode(String fileName);
}

RmvbFile rmv视频文件（具体的实现化角色 ）

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 16:47
 **/
//rmv视频文件（具体的实现化角色 ）
public class RmvbFile implements VideoFile {
    public void decode(String fileName) {
        System.out.println("rmvb视频文件:" + fileName);
    }
}

AviFile avi视频文件（具体的实现化角色 ）

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 16:46
 **/
//avi视频文件（具体的实现化角色 ）
public class AviFile implements VideoFile {
    public void decode(String fileName) {
        System.out.println("avi视屏文件:" + fileName);
    }
}

OpratingSystem 抽象的操作系统类（抽象变化角色)

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 16:48
 **/
//抽象的操作系统类（抽象变化角色)
public abstract class OpratingSystem {
//    声明videFile变量
    protected VideoFile videoFile;
    public OpratingSystem(VideoFile videoFile){
        this.videoFile = videoFile;
    }
    public abstract void play(String fileName);
}

Mac 操作系统（扩展抽象化角色）

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 18:49
 **/
//Mac 操作系统（扩展抽象化角色）
public class Mac extends OpratingSystem {
    public Mac(VideoFile videoFile) {
        super(videoFile);
    }
    @Override
    public void play(String fileName) {
        videoFile.decode(fileName);
    }
}

Windows 扩展抽象化角色（windows操作系统）

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 18:41
 **/
//扩展抽象化角色（windows操作系统）
public class Windows extends OpratingSystem{
    public Windows(VideoFile videoFile) {
        super(videoFile);
    }
    @Override
    public void play(String fileName) {
        videoFile.decode(fileName);
    }
}

Client

package com.hejiawang.pattern.bridge;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 18:50
 **/
public class Client {
    public static void main(String[] args) {
//        创建mac系统对象
        OpratingSystem system = new Mac(new AviFile());
//        使用操作系统播放视频文件
        system.play("战狼三");
    }
}

打印结果

5.外观模式

1.案例

TV

package com.hejiawang.pattern.facade;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:04
 **/
public class TV {
    public void on (){
        System.out.println("打开电视机。。。。");
    }
    public void off (){
        System.out.println("关闭电视机。。。。");
    }
}

Light

package com.hejiawang.pattern.facade;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:03
 **/
public class Light {

    public void on (){
        System.out.println("打开电灯。。。。");
    }
    public void off (){
        System.out.println("关闭电灯。。。。");
    }
}

AirCondition

package com.hejiawang.pattern.facade;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:05
 **/
public class AirCondition {
    public void on (){
        System.out.println("打开空调。。。。");
    }
    public void off (){
        System.out.println("关闭空调。。。。");
    }
}

SmartAplliancesFacade

package com.hejiawang.pattern.facade;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:05
 **/
public class SmartAplliancesFacade {

//    聚合电灯对象，电视机对象，空调对象
    private Light light;
    private TV tv;
    private AirCondition airCondition;

    public SmartAplliancesFacade() {
        light = new Light();
        tv = new TV();
        airCondition = new AirCondition();
    }
//    通过语言控制
    public  void say (String message){
        if (message.contains("打开")){
            on();
        }else if(message.contains("关闭")){
            off();
        } else {
            System.out.println("我听不懂你说的！！！");
        }
    }
//    一键打开方法
    private void on(){
        light.on();
        tv.on();
        airCondition.on();
    }
    //    一键关闭方法
    private void off(){
        light.off();
        tv.off();
        airCondition.off();
    }
}

Client

package com.hejiawang.pattern.facade;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:10
 **/
public class Client {
    public static void main(String[] args) {
//        创建智能音箱对象
        SmartAplliancesFacade facade =  new SmartAplliancesFacade();
//        控制家电
        facade.say("打开家电");
        System.out.println("=======");
        facade.say("关闭家电");
    }
}

2.源码解析

6.组合模式

1.案例

代码实现菜单

MenuComponent 属于抽象根节点

package com.hejiawang.pattern.combination;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:32
 **/
//菜单组件 属于抽象根节点
public abstract class MenuComponent {
//    菜单组件的名称
    protected String name;
//    菜单组件的层级
    protected int level;
//    添加子菜单
    public void add(MenuComponent menuComponent){
        throw new UnsupportedOperationException();
    }
//    移除子菜单
    public void remove(MenuComponent menuComponent){
        throw new UnsupportedOperationException();
    }
//    获取指定的子菜单
    public MenuComponent getChild(int index){
        throw new UnsupportedOperationException();
    }
//    获取菜单或者菜单项的名称
    public String getName(){
        return name;
    }
//    打印菜单名称的方法（包括子菜单和子菜单项）
    public abstract void print();
}

Menu 菜单类：属于树枝节点

package com.hejiawang.pattern.combination;

import java.util.ArrayList;
import java.util.List;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:37
 **/
//菜单类：属于树枝节点
public class Menu extends MenuComponent{
//    菜单可以有多个子菜单或者子菜单项
    private List<MenuComponent> menuComponentList = new ArrayList<MenuComponent>();

    public Menu(String name,int level) {
        this.name = name;
        this.level = level;
    }

    @Override
    public void add(MenuComponent menuComponent) {
        menuComponentList.add(menuComponent);
    }

    @Override
    public void remove(MenuComponent menuComponent) {
        menuComponentList.remove(menuComponent);
    }

    @Override
    public MenuComponent getChild(int index) {
        return menuComponentList.get(index);
    }

    @Override
    public void print() {
//      打印菜单名称
        for (int i = 0 ; i < level ; i++){
            System.out.print("--");
        }
        System.out.println(name);
//        打印子菜单或者子菜单项名称
        for (MenuComponent component:menuComponentList){
            component.print();
        }
    }
}

MenuItem 菜单项类：属于叶子节点

package com.hejiawang.pattern.combination;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:45
 **/
//菜单项类：属于叶子节点
public class MenuItem extends MenuComponent {
    public MenuItem(String name,int level) {
        this.name = name ;
        this.level = level;
    }
    @Override
    public void print() {
//      打印菜单项的名称
        for (int i = 0 ; i < level ; i++){
            System.out.print("--");
        }
        System.out.println(name);
    }
}

Client

package com.hejiawang.pattern.combination;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 19:49
 **/
public class Client {
    public static void main(String[] args) {
//        创建菜单树
        MenuComponent menu1 = new Menu("菜单管理",2);
        menu1.add(new MenuItem("页面访问",3));
        menu1.add(new MenuItem("展开菜单",3));
        menu1.add(new MenuItem("编辑菜单",3));
        menu1.add(new MenuItem("删除菜单",3));
        menu1.add(new MenuItem("新增菜单",3));
        MenuComponent menu2 = new Menu("权限管理",2);
        menu2.add(new MenuItem("页面访问",3));
        menu2.add(new MenuItem("提交保存",3));
        MenuComponent menu3 = new Menu("角色管理",2);
        menu3.add(new MenuItem("页面访问",3));
        menu3.add(new MenuItem("新增角色",3));
        menu3.add(new MenuItem("修改角色",3));
//        创建一级菜单
        MenuComponent component = new Menu("系统管理",1);
        component.add(menu1);
        component.add(menu2);
        component.add(menu3);
//        打印菜单名称（如果有子菜单，一块带你）
        component.print();
    }
}

打印结果

7.享元模式

1.案例

AbstractBox

package com.hejiawang.pattern.flyweight;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:23
 **/
//  抽象享元角色
public abstract class AbstractBox {

//    获取图形的方法
    public abstract String getShape();

//    显示图形及颜色
    public void display(String color){
        System.out.println("方块形状:"+getShape()+",颜色:" + color);
    }
}

IBOX

package com.hejiawang.pattern.flyweight;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:26
 **/
//I图形类（具体享元角色）
public class IBOX extends AbstractBox {
    @Override
    public String getShape() {
        return "I";
    }
}

LBOX

package com.hejiawang.pattern.flyweight;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:26
 **/
//L图形类（具体享元角色）
public class LBOX extends AbstractBox {
    @Override
    public String getShape() {
        return "L";
    }
}

OBOX

package com.hejiawang.pattern.flyweight;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:26
 **/
//O图形类（具体享元角色）
public class OBOX extends AbstractBox {
    @Override
    public String getShape() {
        return "O";
    }
}

BoxFactory

package com.hejiawang.pattern.flyweight;

import javax.swing.*;
import java.util.HashMap;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:28
 **/
//  工厂类，将该类设计为单例
public class BoxFactory {

    private HashMap<String,AbstractBox> map;

//    在构造方法中进行初始化操作
    private BoxFactory() {
        map = new HashMap<String, AbstractBox>();
        map.put("I",new IBOX());
        map.put("L",new LBOX());
        map.put("O",new OBOX());
    }
    private static BoxFactory factory = new BoxFactory();
//  提供一个方法获取该工厂类对象
    public static BoxFactory getInstance(){
        return factory;
    }
//    根据名称获取图形对象
    public AbstractBox getShape(String name){
        return map.get(name);
    }
}

Client

package com.hejiawang.pattern.flyweight;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:33
 **/
public class Client {
    public static void main(String[] args) {
//        获取I图形对象
        AbstractBox box1 = BoxFactory.getInstance().getShape("I");
        box1.display("灰色");
//        获取L图形对象
        AbstractBox box2 = BoxFactory.getInstance().getShape("L");
        box2.display("绿色");
        //        获取O图形对象
        AbstractBox box3 = BoxFactory.getInstance().getShape("O");
        box3.display("灰色");
        //        获取O图形对象
        AbstractBox box4 = BoxFactory.getInstance().getShape("O");
        box4.display("红色");
//
        System.out.println("两次获取到的O图形对象是否是同一个对象:"+(box3 == box4));
    }
}

打印结果

2.jdk源码

Interger使用了享元模式

package com.hejiawang.pattern.flyweight.jdk;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 20:43
 **/
public class Demo {
    public static void main(String[] args) {
        Integer i1 = 127;
        Integer i2 = 127;
        System.out.println("i1和i2对象是否是同一个对象？" + (i1 == i2));
        Integer i3 = 128;
        Integer i4 = 128;
        System.out.println("i3和i4对象是否是同一个对象？" + (i3 == i4));
    }
}

打印结果

反编译

    public static Integer valueOf(int i) {
        if (i >= IntegerCache.low && i <= IntegerCache.high)
            return IntegerCache.cache[i + (-IntegerCache.low)];
        return new Integer(i);
    }
    
    private static class IntegerCache {
        static final int low = -128;
        static final int high;
        static final Integer cache[];

        static {
            // high value may be configured by property
            int h = 127;
            String integerCacheHighPropValue =
                sun.misc.VM.getSavedProperty("java.lang.Integer.IntegerCache.high");
            if (integerCacheHighPropValue != null) {
                try {
                    int i = parseInt(integerCacheHighPropValue);
                    i = Math.max(i, 127);
                    // Maximum array size is Integer.MAX_VALUE
                    h = Math.min(i, Integer.MAX_VALUE - (-low) -1);
                } catch( NumberFormatException nfe) {
                    // If the property cannot be parsed into an int, ignore it.
                }
            }
            high = h;

            cache = new Integer[(high - low) + 1];
            int j = low;
            for(int k = 0; k < cache.length; k++)
                cache[k] = new Integer(j++);

            // range [-128, 127] must be interned (JLS7 5.1.7)
            assert IntegerCache.high >= 127;
        }

        private IntegerCache() {}
    }

3.行为型模式

1.模板方法模式

1.案例

AbstractClass

package com.hejiawang.pattern.template;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:08
 **/
//抽象类
public abstract  class AbstractClass {
//    模板方法定义
    public final void cookProcess(){
        pourOil();
        heatOil();
        pourVegetable();
        pourSauce();
        fry();
    }
    public void pourOil(){
        System.out.println("倒油");
    }
//    第二步：热油是一样的，所以直接实现
    public void heatOil(){
        System.out.println("热油");
    }
//    第三步：倒蔬菜是不一样的（一个下包菜，一个下菜心）
    public abstract void pourVegetable();
//    第四步：倒调味料是不一样的
    public abstract void pourSauce();
//    第五步：翻炒是一样的，所以直接实现
    public void fry(){
        System.out.println("翻炒");
    }
}

ConcreteClass_BaoCai

package com.hejiawang.pattern.template;

import com.hejiawang.pattern.flyweight.AbstractBox;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:14
 **/
//  炒包菜类
public class ConcreteClass_BaoCai extends AbstractClass {
    @Override
    public void pourVegetable() {
        System.out.println("下锅的蔬菜是包菜");
    }

    @Override
    public void pourSauce() {
        System.out.println("下锅的酱料是辣椒");
    }
}

ConcreteClass_CaiXin

package com.hejiawang.pattern.template;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:15
 **/
public class ConcreteClass_CaiXin extends AbstractClass {
    @Override
    public void pourVegetable() {
        System.out.println("下锅的蔬菜是菜心");
    }
    @Override
    public void pourSauce() {
        System.out.println("下锅的酱料是蒜蓉");

    }
}

Client

package com.hejiawang.pattern.template;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:16
 **/
public class Client {
    public static void main(String[] args) {
//            炒包菜
//          创建对象
        ConcreteClass_BaoCai baoCai = new ConcreteClass_BaoCai();
//      调用炒菜的功能
        baoCai.cookProcess();
    }
}

打印结果

2.jdk源码

    public abstract int read() throws IOException;
    
    public int read(byte b[]) throws IOException {
        return read(b, 0, b.length);
    }
    
   public int read(byte b[], int off, int len) throws IOException {
        if (b == null) {
            throw new NullPointerException();
        } else if (off < 0 || len < 0 || len > b.length - off) {
            throw new IndexOutOfBoundsException();
        } else if (len == 0) {
            return 0;
        }

        int c = read();              //调用了无参的read方法，即必须要求子类的实现的read方法，即实现了反向控制
        if (c == -1) {
            return -1;
        }
        b[off] = (byte)c;

        int i = 1;
        try {
            for (; i < len ; i++) {
                c = read();
                if (c == -1) {
                    break;
                }
                b[off + i] = (byte)c;
            }
        } catch (IOException ee) {
        }
        return i;
    }

2.策略模式

1.案例

Strategy

package com.hejiawang.pattern.strategy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:31
 **/
//抽象策略类
public interface Strategy {
    void show();
}

StrategyA

package com.hejiawang.pattern.strategy;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:32
 **/
//具体策略类
public class StrategyA implements Strategy {
    public void show() {
        System.out.println("买一送一");
    }
}

StrategyB

package com.hejiawang.pattern.strategy;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:33
 **/
public class StrategyB implements Strategy {
    public void show() {
        System.out.println("满200减50");
    }
}

StrategyC

package com.hejiawang.pattern.strategy;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:33
 **/
public class StrategyC implements Strategy {
    public void show() {
        System.out.println("满1000减200");
    }
}

SalesMan

package com.hejiawang.pattern.strategy;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:34
 **/
public class SalesMan {
//      聚合策略类对象
    private Strategy strategy;
    public SalesMan(Strategy strategy){
        this.strategy = strategy;
    }
//   有促销员展示促销活动给用户
    public void salesManShow(){
        strategy.show();
    }
}

Client

package com.hejiawang.pattern.strategy;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-04 21:36
 **/
public class Client {
    public static void main(String[] args) {
//        春节来了，使用春节促销活动
        SalesMan salesMan =  new SalesMan(new StrategyA());
        salesMan.salesManShow();
        System.out.println("===============");
        //        中秋节到了，使用中秋节的促销
        SalesMan salesMan2 =  new SalesMan(new StrategyB());
        salesMan2.salesManShow();
//       圣诞节到了，使用中秋节的促销
        System.out.println("===============");
        SalesMan salesMan3 =  new SalesMan(new StrategyC());
        salesMan3.salesManShow();
    }
}

打印结果

2.jdk源码

3.命令模式

1.案例

Order

package com.hejiawang.pattern.command;
import java.util.HashMap;
import java.util.Map;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 09:50
 **/
//订单类
public class Order {
//    餐桌号
    private int diningTable;
//    所下的餐品及份数
    private Map<String,Integer> foodDir = new HashMap<String, Integer>();
    public int getDiningTable() {
        return diningTable;
    }
    public void setDiningTable(int diningTable) {
        this.diningTable = diningTable;
    }
    public Map<String, Integer> getFoodDir() {
        return foodDir;
    }
    public void setFood(String name,int num) {
        foodDir.put(name,num);
    }
}

Command

package com.hejiawang.pattern.command;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 09:55
 **/
//抽象命令类
public interface Command {
    void execute();
}

OrderCommand

package com.hejiawang.pattern.command;

import java.util.Map;
import java.util.Set;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 09:57
 **/
public class OrderCommand implements Command {
//    持有接受者对象
    private SenioChef receiver;
    private Order order;

    public OrderCommand(SenioChef receiver,Order order){
        this.receiver = receiver;
        this.order = order;
    }
    public void execute() {
        System.out.println(order.getDiningTable()+"桌的订单：");
        Map<String,Integer> foodDir = order.getFoodDir();
//        遍历map集合
        Set<String> keys = foodDir.keySet();
        for (String foodName : keys){
            receiver.makeFood(foodName,foodDir.get(foodName));
        }
        System.out.println(order.getDiningTable()+"桌的饭准备完毕！！！");
    }
}

SenioChef

package com.hejiawang.pattern.command;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 09:54
 **/
public class SenioChef {
    public void makeFood(String name,int num){
        System.out.println(num + "份" + name);
    }
}

Client

package com.hejiawang.pattern.command;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 10:24
 **/
public class Client {
    public static void main(String[] args) {
        //    创建第一个订单对象
        Order order1 = new Order();
        order1.setDiningTable(1);
        order1.setFood("西红柿鸡蛋面",1);
        order1.setFood("小杯可乐",2);
        //    创建第二个订单对象
        Order order2 = new Order();
        order2.setDiningTable(2);
        order2.setFood("尖椒肉丝盖饭",1);
        order2.setFood("小杯雪碧",1);
//        创建厨师对象
        SenioChef receiver = new SenioChef();
//        创建命令对象
        OrderCommand cmd1 = new OrderCommand(receiver,order1);
        OrderCommand cmd2 = new OrderCommand(receiver,order2);
//        创建调用者（服务员对象）
        Waitor invoke = new Waitor();
        invoke.setCommands(cmd1);
        invoke.setCommands(cmd2);
//        让服务员发起命令
        invoke.orderUp();
    }
}

打印结果

2.jdk源码

4.责任链模式

1.案例

Handler

package com.hejiawang.pattern.responsibility;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 12:17
 **/
//  抽象处理者类
public abstract class Handler {
    protected final  static int NUM_ONE = 1 ;
    protected final  static int NUM_THREE = 3 ;
    protected final  static int NUM_SEVEN = 7 ;

//    该领导处理的请求天数区间
    private int numStart;
    private int numEnd;

//    声明后继者（声明上级领导）
    private Handler nextHandler;

    public Handler(int numStart){
        this.numStart = numStart;
    }

    public Handler(int numStart, int numEnd) {
        this.numStart = numStart;
        this.numEnd = numEnd;
    }

//    设置上级领导对象
    public void setNextHandler(Handler nextHandler) {
        this.nextHandler = nextHandler;
    }

//    各级领导处理请假条的方法`在这里插入代码片`
    protected abstract void handlerLeave(LeaveRequest leaveRequest);

//    提交请假条
    public final void submit(LeaveRequest leaveRequest){
//        该领导进行审批
        this.handlerLeave(leaveRequest);
        if (this.nextHandler != null && leaveRequest.getNum() > this.numEnd){
//            提交给上级领导进行审批
            this.nextHandler.submit(leaveRequest);
        }else{
            System.out.println("流程结束");
        }
    }
}

GroupLeader

package com.hejiawang.pattern.responsibility;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 12:26
 **/
//小组长类
public class GroupLeader extends Handler {

    public GroupLeader() {
        super(0,Handler.NUM_ONE);
    }
    @Override
    protected void handlerLeave(LeaveRequest leaveRequest) {
        System.out.println(leaveRequest.getName() + "请假" + leaveRequest.getNum() + "天，"+leaveRequest.getContent());
        System.out.println("小组长审批：同意");
    }
}

Manager

package com.hejiawang.pattern.responsibility;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 12:26
 **/
//部门经理类
public class Manager extends Handler {

    public Manager() {
        super(Handler.NUM_ONE,Handler.NUM_THREE);
    }

    @Override
    protected void handlerLeave(LeaveRequest leaveRequest) {
        System.out.println(leaveRequest.getName() + "请假" + leaveRequest.getNum() + "天，"+leaveRequest.getContent());
        System.out.println("部门经理审批：同意");
    }
}

GeneralManager

package com.hejiawang.pattern.responsibility;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 12:26
 **/
//总经理类
public class GeneralManager extends Handler {

    public GeneralManager() {
        super(Handler.NUM_THREE,Handler.NUM_SEVEN);
    }

    @Override
    protected void handlerLeave(LeaveRequest leaveRequest) {
        System.out.println(leaveRequest.getName() + "请假" + leaveRequest.getNum() + "天，"+leaveRequest.getContent());
        System.out.println("总经理审批：同意");
    }
}

LeaveRequest

package com.hejiawang.pattern.responsibility;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 12:15
 **/
//  请假条类
public class LeaveRequest {
//      姓名
    private String name;
//    请假天数
    private int num;
//    请假内容
    private String content;

    public LeaveRequest(String name, int num, String content) {
        this.name = name;
        this.num = num;
        this.content = content;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getNum() {
        return num;
    }

    public void setNum(int num) {
        this.num = num;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }
}

Client

package com.hejiawang.pattern.responsibility;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 12:33
 **/
public class Client {
    public static void main(String[] args) {
//        创建一个请假条对象
        LeaveRequest leaveRequest = new LeaveRequest("小明",4,"身体不适");
//        创建各级领导对象
        GroupLeader groupLeader = new GroupLeader();
        Manager manager = new Manager();
        GeneralManager generalManager = new GeneralManager();

//        设置处理链
        groupLeader.setNextHandler(manager);
        manager.setNextHandler(generalManager);
//        小明提交请假申请
        groupLeader.submit(leaveRequest);

    }
}

打印结果

2.jdk源码分析

打印结果

5.状态模式

1.原始案例

ILift

package com.hejiawang.pattern.state.before;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 13:11
 **/
//  电梯接口
public interface ILift {
//  定义四哥电梯状态的常量
    int OPENING_STATE = 1;
    int CLOSING_STATE = 2;
    int RUNNING_STATE = 3;
    int STOPPING_STATE = 4;
//    设置电梯状态的功能
    void setState(int state);

//    电梯操作功能
    void open();

    void close();

    void run();

    void stop();
}

Lift

package com.hejiawang.pattern.state.before;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 13:14
 **/
public class Lift implements ILift {
//    声明一个记录当前电梯的状态
    private int state ;

    public void setState(int state) {
     this.state = state;
    }

    public void open() {
        switch (state){
            case OPENING_STATE :
//                什么事都不做
                break;
            case CLOSING_STATE :
                System.out.println("电梯门打开了。。。");
                setState(OPENING_STATE);
                break;
            case RUNNING_STATE :
//                什么事都不做
                break;
            case STOPPING_STATE :
                System.out.println("电梯门打开了。。。");
                setState(OPENING_STATE);
                break;
        }
    }

    public void close() {
        switch (state){
            case OPENING_STATE :
                System.out.println("电梯门关了。。。");
                setState(CLOSING_STATE);
                break;
            case CLOSING_STATE :
//                什么事都不做
                break;
            case RUNNING_STATE :
//                什么事都不做
                break;
            case STOPPING_STATE :
//                什么事都不做
                break;
        }
    }

    public void run() {
        switch (state){
            case OPENING_STATE :
//                什么事都不做
                break;
            case CLOSING_STATE :
                System.out.println("电梯开始运行了。。。");
                setState(RUNNING_STATE);
                break;
            case RUNNING_STATE :
//                什么事都不做
                break;
            case STOPPING_STATE :
                System.out.println("电梯开始运行了。。。");
                setState(RUNNING_STATE);
                break;
        }
    }

    public void stop() {
        switch (state){
            case OPENING_STATE :
//                什么事都不做
                break;
            case CLOSING_STATE :
                System.out.println("电梯停止了。。。");
                setState(STOPPING_STATE);
                break;
            case RUNNING_STATE :
                System.out.println("电梯停止了。。。");
                setState(STOPPING_STATE);
                break;
            case STOPPING_STATE :
//                什么事都不做
                break;
        }
    }
}

Client

package com.hejiawang.pattern.state.before;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:40
 **/
public class Client {
    public static void main(String[] args) {
//        创建电梯对象
        Lift lift = new Lift();
//        设置电梯当前状态
        lift.setState(ILift.OPENING_STATE);
        lift.open();
        lift.close();
        lift.run();
        lift.stop();

    }
}

打印结果

2.状态模式修改后案例

Context

package com.hejiawang.pattern.state.after;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:48
 **/
//环境角色类
public class Context {
    public final static OpeningState OPENING_STATE = new OpeningState();
    public final static ClosingState CLOSING_STATE = new ClosingState();
    public final static RunningState RUNNING_STATE = new RunningState();
    public final static StoppingState STOPPING_STATE = new StoppingState();
//    定义一个当前电梯状态变量
    private LiftState liftState;
    public LiftState getLiftState() {
        return liftState;
    }
//    设置当前状态对象
    public void setLiftState(LiftState liftState) {
        this.liftState = liftState;
//        设置当前状态对象中的context对象
        this.liftState.setContext(this);
    }
    public void open(){
        this.liftState.open();
    }
    public void close(){
        this.liftState.close();
    }
    public void run(){
        this.liftState.run();
    }
    public void stop(){
        this.liftState.stop();
    }
}

LiftState

package com.hejiawang.pattern.state.after;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:47
 **/
//抽象状态类
public abstract class LiftState {
//    声明环境角色类变量
    protected Context context;

    public void setContext(Context context) {
        this.context = context;
    }
//    电梯开启操作
    public abstract void open();
//    电梯关闭操作
    public abstract void close();
//    电梯运行操作
    public abstract void run();
//    电梯停止操作
    public abstract void stop();
}

RunningState

package com.hejiawang.pattern.state.after;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:51
 **/
//电梯运行状态类
public class RunningState extends LiftState {
    //    当前状态要执行的方法
    @Override
    public void open() {
//        什么都不做
    }

    @Override
    public void close() {
//        什么都不做

    }

    @Override
    public void run() {
        System.out.println("电梯运行。。。");
    }

    @Override
    public void stop() {
        super.context.setLiftState(Context.STOPPING_STATE);
        super.context.getLiftState().stop();
    }
}

StoppingState

package com.hejiawang.pattern.state.after;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:52
 **/
//电梯停止状态类
public class StoppingState extends LiftState {
    //    当前状态要执行的方法
    @Override
    public void open() {
//        状态修改
        super.context.setLiftState(Context.OPENING_STATE);
        super.context.getLiftState().open();
    }

    @Override
    public void close() {
        super.context.setLiftState(Context.CLOSING_STATE);
        super.context.getLiftState().close();
    }

    @Override
    public void run() {
        super.context.setLiftState(Context.RUNNING_STATE);
        super.context.run();
    }

    @Override
    public void stop() {
        System.out.println("电梯停止。。。");
    }
}

OpeningState

package com.hejiawang.pattern.state.after;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:49
 **/
//电梯开启状态类
public class OpeningState extends LiftState{
//    当前状态要执行的方法
    @Override
    public void open() {
        System.out.println("电梯门开启。。。");
    }

    @Override
    public void close() {
//        修改状态
        super.context.setLiftState(Context.CLOSING_STATE);
//        调用当前状态中context中的close方法
        super.context.close();
    }

    @Override
    public void run() {
//        什么都不做
    }

    @Override
    public void stop() {
//        什么都不做
    }
}

ClosingState

package com.hejiawang.pattern.state.after;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-05 14:51
 **/
public class ClosingState extends LiftState {
    @Override
    public void open() {
        //        修改状态
        super.context.setLiftState(Context.OPENING_STATE);
//        调用当前状态中context中的close方法
        super.context.open();
    }

    @Override
    public void close() {
        System.out.println("电梯门关闭。。。");
    }

    @Override
    public void run() {
        //        修改状态
        super.context.setLiftState(Context.RUNNING_STATE);
//        调用当前状态中context中的close方法
        super.context.run();
    }

    @Override
    public void stop() {
        //        修改状态
        super.context.setLiftState(Context.STOPPING_STATE);
//        调用当前状态中context中的close方法
        super.context.stop();
    }
}

Client

package com.hejiawang.pattern.state.after;

import com.hejiawang.pattern.template.ConcreteClass_BaoCai;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 14:23
 **/
public class Client {
    public static void main(String[] args) {
//        创建环境对象
        Context context = new Context();
//        设置当前电梯装填
        context.setLiftState(new ClosingState());
        context.open();
        context.close();
        context.run();
        context.stop();
    }
}

打印结果

6.观察者模式

1.案例

Subject

package com.hejiawang.pattern.observer;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 14:47
 **/
//抽象主题角色类
public interface Subject {
//    添加订阅者
    void attach(Observer observer);

//    删除订阅者
    void detach(Observer observer);

//    通知订阅者
    void notify(String message);
}

Observer

package com.hejiawang.pattern.observer;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 14:48
 **/
//抽象观察者
public interface Observer {
    void update(String message);
}

SubscriptionSubject

package com.hejiawang.pattern.observer;

import java.util.ArrayList;
import java.util.List;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 14:50
 **/
//具体主题角色类
public class SubscriptionSubject implements Subject {
//   定义一个集合，来存储对个观察者对象
    private List<Observer> weiXinUserList = new ArrayList<Observer>();
    public void attach(Observer observer) {
        weiXinUserList.add(observer);
    }
    public void detach(Observer observer) {
        weiXinUserList.remove(observer);
    }
    public void notify(String message) {
        for (Observer observer: weiXinUserList){
//            调用观察者对象中update方法
            observer.update(message );
        }
    }
}

WeiXinUser

package com.hejiawang.pattern.observer;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 14:54
 **/
//具体的观察者角色
public class WeiXinUser implements Observer {
    private String name;

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

    public void update(String message) {
        System.out.println(name + "-" + message);
    }
}

Client

package com.hejiawang.pattern.observer;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 14:56
 **/
public class Client {
    public static void main(String[] args) {
//        1.创建公众号对象
        SubscriptionSubject sbuject = new SubscriptionSubject();
//        2.订阅公众号
        sbuject.attach(new WeiXinUser("飞鸽"));
        sbuject.attach(new WeiXinUser("坤坤"));
        sbuject.attach(new WeiXinUser("肥宅子"));
//        3.公众号更新，发出消息给订阅者（观察者对象）
        sbuject.notify("日服男枪上线了！");
    }
}

打印结果

2.jdk源码分析

继承Observable即是具体主题角色类，集成Observable类，调用notifyObservers()f方法

观察者实现Observer接口重写update方法

7.中介者模式

1.案例

Person

package com.hejiawang.pattern.mediator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:21
 **/
//抽象同事类
public abstract class Person {
    protected String name;
    protected Mediator mediator;

    public Person(String name, Mediator mediator) {
        this.name = name;
        this.mediator = mediator;
    }
}

Tenant

package com.hejiawang.pattern.mediator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:22
 **/
//具体的同事角色类
public class Tenant extends Person {
    public Tenant(String name, Mediator mediator) {
        super(name, mediator);
    }

//    和中介联系（沟通）
    public void constact(String message){
        mediator.constract(message,this);
    }
//    获取信息
    public void getMessage(String message){
        System.out.println("租房者" + name + "获取到的信息是" + message);
    }
}

HouseOwner

package com.hejiawang.pattern.mediator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:25
 **/
public class HouseOwner extends Person {
    public HouseOwner(String name, Mediator mediator) {
        super(name, mediator);
    }
    //    和中介联系（沟通）
    public void constact(String message){
        mediator.constract(message,this);
    }
    //    获取信息
    public void getMessage(String message){
        System.out.println("房主" + name + "获取到的信息是" + message);
    }
}

Mediator

package com.hejiawang.pattern.mediator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:20
 **/
public abstract class Mediator {
    public abstract void constract(String message,Person person);
}

MediatorStructure

package com.hejiawang.pattern.mediator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:27
 **/
//具体的终结者角色类
public class MediatorStructure extends Mediator{
//    聚合房主和租房者对象
    private HouseOwner houseOwner;
    private Tenant tenant;

    public HouseOwner getHouseOwner() {
        return houseOwner;
    }

    public void setHouseOwner(HouseOwner houseOwner) {
        this.houseOwner = houseOwner;
    }

    public Tenant getTenant() {
        return tenant;
    }

    public void setTenant(Tenant tenant) {
        this.tenant = tenant;
    }

    @Override
    public void constract(String message, Person person) {
        if (person ==  tenant){
            tenant.getMessage(message);
        } else {
            houseOwner.getMessage(message);
        }
    }
}

Client

package com.hejiawang.pattern.mediator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:29
 **/
public class Client {
    public static void main(String[] args) {
        //    创建中介者对象
        MediatorStructure mediator = new MediatorStructure();
//    创建租房者对象
        Tenant tenant = new Tenant("肥宅子租房者",mediator);
//    创建房主对象
        HouseOwner houseOwner = new HouseOwner("飞鸽包租公",mediator);

//    中介要知道具体的房主和租房者
        mediator.setTenant(tenant);
        mediator.setHouseOwner(houseOwner);
        tenant.constact("我要租别墅");
        houseOwner.constact("我这里有别墅，你要租吗？");
    }
}

打印结果

8.迭代器模式

1.案例

Student

package com.hejiawang.pattern.iterator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:42
 **/
public class Student {
    private String name;
    private String number;

    public Student() {
    }

    public Student(String name, String number) {
        this.name = name;
        this.number = number;
    }

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", number='" + number + '\'' +
                '}';
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }
}

StudentIterator

package com.hejiawang.pattern.iterator;

//抽象迭代器角色接口
public interface StudentIterator {

//    判断是否还有元素
    boolean hasNext();
//    获取下一个元素
    Student next();
}

StudentIteratorImpl

package com.hejiawang.pattern.iterator;

import java.util.List;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:44
 **/
//具体迭代器角色
public class StudentIteratorImpl implements StudentIterator {

    private List<Student> list;
    private int position = 0; //用来记录遍历时的位置

    public StudentIteratorImpl(List<Student> list) {
        this.list = list;
    }

    public boolean hasNext() {
        return position < list.size();
    }

    public Student next() {
//        从集合中获取指定位置的元素
        Student currentSudent = list.get(position);
        position++;
        return currentSudent;
    }
}

StudentAggregate

package com.hejiawang.pattern.iterator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 15:47
 **/
//抽象聚合角色接口
public interface StudentAggregate {
//    添加学生功能
    void addStudent(Student stu);

//    删除学生功能
    void removeStudent(Student stu);

//    获取迭代器对象功能
    StudentIterator getStudentIterator();
}

StudentAggregateImpl

package com.hejiawang.pattern.iterator;

import java.util.ArrayList;
import java.util.List;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:06
 **/
public class StudentAggregateImpl implements StudentAggregate{

    private List<Student> list = new ArrayList<Student>();

    public void addStudent(Student stu) {
        list.add(stu);
    }

    public void removeStudent(Student stu) {
        list.remove(stu);
    }

    public StudentIterator getStudentIterator() {
        return new StudentIteratorImpl(list);
    }
}

Client

package com.hejiawang.pattern.iterator;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:12
 **/
public class Client {
    public static void main(String[] args) {
//        创建聚合对象
        StudentAggregateImpl aggregate = new StudentAggregateImpl();
//        添加元素
        aggregate.addStudent(new Student("张三","001"));
        aggregate.addStudent(new Student("李四","002"));
        aggregate.addStudent(new Student("王五","003"));
        aggregate.addStudent(new Student("赵六","004"));

//        遍历聚合对象
//        1.获取迭代器对象
        StudentIterator iterator = aggregate.getStudentIterator();
//        2.遍历
        while(iterator.hasNext()){
//            3.获取元素
            Student student = iterator.next();
            System.out.println(student.toString());
        }
    }
}

打印结果

2.jdk源码

public class ArrayList<E> extends AbstractList<E> implements List<E>, RandomAccess, Cloneable, java.io.Serializable{
    public Iterator<E> iterator() {
        return new Itr();
    }
        private class Itr implements Iterator<E> {
                int cursor;       // index of next element to return
        int lastRet = -1; // index of last element returned; -1 if no such
        int expectedModCount = modCount;

        Itr() {}

        public boolean hasNext() {
            return cursor != size;
        }

        @SuppressWarnings("unchecked")
        public E next() {
            checkForComodification();
            int i = cursor;
            if (i >= size)
                throw new NoSuchElementException();
            Object[] elementData = ArrayList.this.elementData;
            if (i >= elementData.length)
                throw new ConcurrentModificationException();
            cursor = i + 1;
            return (E) elementData[lastRet = i];
        }
	}
}

9.访问者模式

1.案例

Animal

package com.hejiawang.pattern.visitor;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:35
 **/
//抽象元素角色类
public interface Animal {
//  接收访问者访问的功能
    void accept(Person person);
}

Cat

package com.hejiawang.pattern.visitor;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:36
 **/
//具体元素角色类（宠物猫）
public class Cat implements Animal {
    public void accept(Person person) {
        person.feed(this);//访问者给宠物猫喂食
        System.out.println("喵喵喵~");
    }
}

Dog

package com.hejiawang.pattern.visitor;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:38
 **/
//具体元素角色类（宠物狗）
public class Dog implements Animal {
    public void accept(Person person) {
        person.feed(this);//访问者给宠物猫喂食
        System.out.println("汪汪汪~");
    }
}

Person

package com.hejiawang.pattern.visitor;

//抽象访问者角色类
public interface Person {
//   喂食宠物狗
    void feed(Cat cat);
//  喂食宠物猫
    void feed(Dog dog);
}

Owner

package com.hejiawang.pattern.visitor;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:39
 **/
//具体访问者角色类（主人）
public class Owner implements Person{
    public void feed(Cat cat) {
        System.out.println("主人喂食猫");
    }

    public void feed(Dog dog) {
        System.out.println("主人喂食狗");

    }
}

Someone

package com.hejiawang.pattern.visitor;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:40
 **/
//具体访问者角色类（其他人）
public class Someone implements Person {
    public void feed(Cat cat) {
        System.out.println("其他人喂食猫");
    }
    public void feed(Dog dog) {
        System.out.println("其他人喂食狗");
    }
}

Home

package com.hejiawang.pattern.visitor;

import java.util.ArrayList;
import java.util.List;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:41
 **/
//对象结构类
public class Home {
//    声明一个稽核对象，用来存储元素对象
    private List<Animal> nodeList = new ArrayList<Animal>();

//    添加元素功能
    public void add(Animal animal){
        nodeList.add(animal);
    }

    public void action(Person person){
//        遍历集合，获取每一个元素，让访问者访问每一个元素
        for (Animal animal:nodeList){
            animal.accept(person);
        }
    }
}

Client

package com.hejiawang.pattern.visitor;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 16:44
 **/
public class Client {
    public static void main(String[] args) {
//        创建Home对象
        Home home = new Home();
        home.add(new Dog());
        home.add(new Cat());
//        创建爱你主任对象
        Owner owner = new Owner();
//        让主任喂食所有的宠物
        home.action(owner);
    }
}

打印结果

2.双分派技术

1.动态分派

2.静态分派

3.双分派

10.备忘录模式

1.案例

1.白箱备忘录模式

GameRole

package com.hejiawang.pattern.memento.white_box;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:09
 **/
//游戏角色类（属于发起人角色）
public class GameRole {
    private int vit; //生命力
    private int atk; //攻击力
    private int def; //防御力
//    初始化内部状态
    public void initState(){
        this.vit = 100;
        this.atk = 100;
        this.def = 100;
    }
//    战斗
    public void fight(){
        this.vit = 0;
        this.atk = 0;
        this.def = 0;
    }
    //    保存角色状态功能
    public RoleStateMemento saveState(){
        return new RoleStateMemento(vit,atk,def);
    }

    //    恢复角色状态
    public void recoverState(RoleStateMemento roleStateMemento){
//        将备忘录中存储的状态复制给当前对象的成员
        this.vit = roleStateMemento.getVit();
        this.atk = roleStateMemento.getAtk();
        this.def = roleStateMemento.getDef();
    }
    //    展示状态功能
    public void stateDisplay(){
        System.out.println("角色生命力" + vit);
        System.out.println("角色攻击力" + atk);
        System.out.println("角色防御力" + def);
    }

    public int getVit() {
        return vit;
    }

    public void setVit(int vit) {
        this.vit = vit;
    }

    public int getAtk() {
        return atk;
    }

    public void setAtk(int atk) {
        this.atk = atk;
    }

    public int getDef() {
        return def;
    }

    public void setDef(int def) {
        this.def = def;
    }
}

RoleStateMemento

package com.hejiawang.pattern.memento.white_box;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:12
 **/
//备忘录角色类
public class RoleStateMemento {
    private int vit; //生命力
    private int atk; //攻击力
    private int def; //防御力

    public RoleStateMemento() {
    }

    public RoleStateMemento(int vit, int atk, int def) {
        this.vit = vit;
        this.atk = atk;
        this.def = def;
    }

    public int getVit() {
        return vit;
    }

    public void setVit(int vit) {
        this.vit = vit;
    }

    public int getAtk() {
        return atk;
    }

    public void setAtk(int atk) {
        this.atk = atk;
    }

    public int getDef() {
        return def;
    }

    public void setDef(int def) {
        this.def = def;
    }
}

RoleStateCaretaker

package com.hejiawang.pattern.memento.white_box;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:19
 **/
//备忘录对象管理对象
public class RoleStateCaretaker {
//    声明RoleStateMemento类型的变量
    private RoleStateMemento roleStateMemento;

    public RoleStateMemento getRoleStateMemento() {
        return roleStateMemento;
    }

    public void setRoleStateMemento(RoleStateMemento roleStateMemento) {
        this.roleStateMemento = roleStateMemento;
    }
}

Client

package com.hejiawang.pattern.memento.white_box;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:20
 **/
public class Client {
    public static void main(String[] args) {
        System.out.println("---------作战前-----------");
        GameRole gameRole = new GameRole();
        gameRole.initState();
        gameRole.stateDisplay();

//        将该角色内部状态进行备份
        RoleStateCaretaker roleStateCaretaker = new RoleStateCaretaker();
        roleStateCaretaker.setRoleStateMemento(gameRole.saveState());

        System.out.println("---------作战后-----------");
//      损耗严重
        gameRole.fight();
        gameRole.stateDisplay();
        System.out.println("---------恢复之前的状态-----------");
        gameRole.recoverState(roleStateCaretaker.getRoleStateMemento());
        gameRole.stateDisplay();

    }
}

打印结果

2.黑箱备忘录模式

Memento

package com.hejiawang.pattern.memento.black_box;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:30
 **/
//备忘录接口，对外提供窄接口
public interface Memento {
}

RoleStateCaretaker

package com.hejiawang.pattern.memento.black_box;

import com.hejiawang.pattern.memento.white_box.RoleStateMemento;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:19
 **/
//备忘录对象管理对象
public class RoleStateCaretaker {
//    声明RoleStateMemento类型的变量
    private Memento memento;

    public Memento getMemento() {
        return memento;
    }

    public void setMemento(Memento memento) {
        this.memento = memento;
    }
}

GameRole

package com.hejiawang.pattern.memento.black_box;
/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:09
 **/
//游戏角色类（属于发起人角色）
public class GameRole  {
    private int vit; //生命力
    private int atk; //攻击力
    private int def; //防御力

    private class RoleStateMemento implements Memento{
        private int vit; //生命力
        private int atk; //攻击力
        private int def; //防御力

        public RoleStateMemento() {
        }

        public RoleStateMemento(int vit, int atk, int def) {
            this.vit = vit;
            this.atk = atk;
            this.def = def;
        }

        public int getVit() {
            return vit;
        }

        public void setVit(int vit) {
            this.vit = vit;
        }

        public int getAtk() {
            return atk;
        }

        public void setAtk(int atk) {
            this.atk = atk;
        }

        public int getDef() {
            return def;
        }

        public void setDef(int def) {
            this.def = def;
        }
    }

//    初始化内部状态
    public void initState(){
        this.vit = 100;
        this.atk = 100;
        this.def = 100;
    }
//    战斗
    public void fight(){
        this.vit = 0;
        this.atk = 0;
        this.def = 0;
    }
    //    保存角色状态功能
    public RoleStateMemento saveState(){
        return new RoleStateMemento(vit,atk,def);
    }

    //    恢复角色状态
    public void recoverState(Memento memento){
        RoleStateMemento roleStateMemento = (RoleStateMemento)memento;
//        将备忘录中存储的状态复制给当前对象的成员
        this.vit = roleStateMemento.getVit();
        this.atk = roleStateMemento.getAtk();
        this.def = roleStateMemento.getDef();
    }
    //    展示状态功能
    public void stateDisplay(){
        System.out.println("角色生命力" + vit);
        System.out.println("角色攻击力" + atk);
        System.out.println("角色防御力" + def);
    }

    public int getVit() {
        return vit;
    }

    public void setVit(int vit) {
        this.vit = vit;
    }

    public int getAtk() {
        return atk;
    }

    public void setAtk(int atk) {
        this.atk = atk;
    }

    public int getDef() {
        return def;
    }

    public void setDef(int def) {
        this.def = def;
    }
}

Client

package com.hejiawang.pattern.memento.black_box;


/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:20
 **/
public class Client {
    public static void main(String[] args) {
        System.out.println("---------作战前-----------");
        GameRole gameRole = new GameRole();
        gameRole.initState();
        gameRole.stateDisplay();

//        将该角色内部状态进行备份
        RoleStateCaretaker roleStateCaretaker = new RoleStateCaretaker();
        roleStateCaretaker.setMemento(gameRole.saveState());

        System.out.println("---------作战后-----------");
//      损耗严重
        gameRole.fight();
        gameRole.stateDisplay();
        System.out.println("---------恢复之前的状态-----------");
        gameRole.recoverState(roleStateCaretaker.getMemento());
        gameRole.stateDisplay();

    }
}

打印结果

11.解释器模式

1.案例

Context

package com.hejiawang.pattern.interpreter;
import java.util.HashMap;
import java.util.Map;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:46
 **/
//环境角色类
public class Context {
//    定义一个map稽核，用来存储变量及对应的值
    private Map<Variable,Integer> map = new HashMap<Variable,Integer>();
//    添加变量的功能
    public void assign(Variable var,Integer value ){
        map.put(var,value);
    }
//    根据变量获取对应的值
    public int getValue(Variable var){
        return map.get(var);
    }
}

AbstractExperssion

package com.hejiawang.pattern.interpreter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:45
 **/
//抽象表达式类
public abstract class AbstractExperssion {

    public abstract int interpreter(Context context);
}

Variable

package com.hejiawang.pattern.interpreter;

import com.hejiawang.pattern.template.AbstractClass;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:47
 **/
//变量类
public class Variable extends AbstractExperssion {
//    声明存储变量名的成员变量
    private String name;

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

    @Override
    public String toString() {
        return  name;
    }

    @Override
    public int interpreter(Context context) {
        return context.getValue(this);
    }
}

Minus

package com.hejiawang.pattern.interpreter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:49
 **/
//减法表达式类
public class Minus extends AbstractExperssion{
//    -号左边的表达式
    private AbstractExperssion left;

    //    -号右边的表达式
    private AbstractExperssion right;

    public Minus(AbstractExperssion left, AbstractExperssion right) {
        this.left = left;
        this.right = right;
    }

    @Override
    public int interpreter(Context context) {
//        将左边表达式的结果和右边表达式的结果相加 2-3
        return left.interpreter(context) - right.interpreter(context);
    }

    @Override
    public String toString() {
        return "("+ left.toString() + " - " + right.toString() + ")";
    }
}

Plus

package com.hejiawang.pattern.interpreter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:49
 **/
//加法表达式类
public class Plus extends AbstractExperssion{
//    +号左边的表达式
    private AbstractExperssion left;

    //    +号右边的表达式
    private AbstractExperssion right;

    public Plus(AbstractExperssion left, AbstractExperssion right) {
        this.left = left;
        this.right = right;
    }

    @Override
    public int interpreter(Context context) {
//        将左边表达式的结果和右边表达式的结果相加 2+3
        return left.interpreter(context) + right.interpreter(context);
    }

    @Override
    public String toString() {
        return "("+ left.toString() + " + " + right.toString() + ")";
    }
}

Client

package com.hejiawang.pattern.interpreter;

/**
 * @description:
 * @author: Mr.Wang
 * @create: 2022-07-09 17:57
 **/
public class Client {
    public static void main(String[] args) {
        Context context = new Context();
//        创建多个变量
        Variable a = new Variable("a");
        Variable b = new Variable("b");
        Variable c = new Variable("c");
        Variable d = new Variable("d");

//        将环境变量存储到环境对象中
        context.assign(a,1);
        context.assign(b,2);
        context.assign(c,3);
        context.assign(d,4);

//        获取抽象语法树  a+b-c+d
        AbstractExperssion experssion = new Minus(a,new Plus(new Minus(b,c),d));

//        计算
        int result = experssion.interpreter(context);
        System.out.println(experssion + " = " + result);
    }
}

打印结果