设计模式-状态模式，命令模式

Author: dolyw

DesignPattern/src/main/java/com/design/command/Command.java

@@ -0,0 +1,15 @@
+package com.design.command;
+
+/**
+ * 抽象命令
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public abstract class Command {
+
+    protected RadioReceived radioReceived = new RadioReceived();
+
+    public abstract void execute();
+
+}

DesignPattern/src/main/java/com/design/command/Invoker.java

@@ -0,0 +1,21 @@
+package com.design.command;
+
+/**
+ * 使用命令对象的入口
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public class Invoker {
+
+    private Command command;
+
+    public void setCommand(Command command) {
+        this.command = command;
+    }
+
+    public void action(){
+        this.command.execute();
+    }
+
+}

DesignPattern/src/main/java/com/design/command/Main.java

@@ -0,0 +1,30 @@
+package com.design.command;
+
+/**
+ * 命令模式
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public class Main {
+
+    public static void main(String[] args) {
+        // 定义调用者
+        Invoker invoker = new Invoker();
+        // 创建命令，启动收音机
+        Command command = new StartCommandImpl();
+        // 调用者接受命令
+        invoker.setCommand(command);
+        // 执行命令
+        invoker.action();
+        // 换下个频道
+        command = new NextCommandImpl();
+        invoker.setCommand(command);
+        invoker.action();
+        // 关闭收音机
+        command = new ShutdownCommandImpl();
+        invoker.setCommand(command);
+        invoker.action();
+    }
+
+}

DesignPattern/src/main/java/com/design/command/NextCommandImpl.java

@@ -0,0 +1,14 @@
+package com.design.command;
+
+/**
+ * 切换频道具体命令
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public class NextCommandImpl extends Command {
+    @Override
+    public void execute() {
+        super.radioReceived.next();
+    }
+}

DesignPattern/src/main/java/com/design/command/RadioReceived.java

@@ -0,0 +1,23 @@
+package com.design.command;
+
+/**
+ * 真正的命令执行对象
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public class RadioReceived {
+
+    public void start() {
+        System.out.println("启动收音机");
+    }
+
+    public void next() {
+        System.out.println("切换频道");
+    }
+
+    public void shutdown() {
+        System.out.println("关闭收音机");
+    }
+
+}

DesignPattern/src/main/java/com/design/command/ShutdownCommandImpl.java

@@ -0,0 +1,14 @@
+package com.design.command;
+
+/**
+ * 关闭收音机具体命令
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public class ShutdownCommandImpl extends Command {
+    @Override
+    public void execute() {
+        super.radioReceived.shutdown();
+    }
+}

DesignPattern/src/main/java/com/design/command/StartCommandImpl.java

@@ -0,0 +1,14 @@
+package com.design.command;
+
+/**
+ * 启动收音机具体命令
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 16:05
+ */
+public class StartCommandImpl extends Command {
+    @Override
+    public void execute() {
+        super.radioReceived.start();
+    }
+}

DesignPattern/src/main/java/com/design/state/Main.java

@@ -0,0 +1,26 @@
+package com.design.state;
+
+/**
+ * 状态模式 - 状态机的扭转
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 15:29
+ */
+public class Main {
+
+    public static void main(String[] args) {
+        // 声明环境类
+        OrderContext orderContext = new OrderContext();
+        // 初始化状态
+        OrderState orderState = new OrderCreateStateImpl();
+        // OrderState orderState = new OrderPayStateImpl();
+        orderState.handle(orderContext);
+        // 状态机扭转
+        orderContext.handle();
+        orderContext.handle();
+        orderContext.handle();
+        orderContext.handle();
+        orderContext.handle();
+    }
+
+}

DesignPattern/src/main/java/com/design/state/OrderContext.java

@@ -0,0 +1,23 @@
+package com.design.state;
+
+/**
+ * 订单环境类
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 15:12
+ */
+public class OrderContext {
+
+    private OrderState orderState;
+
+    /**
+     * 处理方法
+     */
+    public void handle() {
+        orderState.handle(this);
+    }
+
+    public void setOrderState(OrderState orderState) {
+        this.orderState = orderState;
+    }
+}

DesignPattern/src/main/java/com/design/state/OrderCreateStateImpl.java

@@ -0,0 +1,17 @@
+package com.design.state;
+
+/**
+ * 订单下单具体状态
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2023/2/2 15:12
+ */
+public class OrderCreateStateImpl extends OrderState {
+
+    @Override
+    public void handle(OrderContext orderContext) {
+        System.out.println("下单");
+        // 可以和享元模式组合，不需要每次都去new具体状态，可以创建一次后重复使用
+        orderContext.setOrderState(new OrderPayStateImpl());
+    }
+}