设计模式学习—19命令模式

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本文链接： https://blog.csdn.net/qq_33334951/article/details/102677934

命令模式

UML

解释说明

• 命令模式：将一个请求封装为一个对象，从而使你可用不同的请求对客户进行参数化；支持请求排队、记录请求日志、支持可撤销操作。

代码实现

• Command.class

public interface Command {
    void execute();
}

• Receiver.class

package learn19;

public class Receiver {
    public void action() {
        System.out.println("Receiver执行!");
    }
}

• ConcreteCommand.class

package learn19;

public class ConcreteCommand implements Command {
    private Receiver receiver;

    public ConcreteCommand(Receiver receiver) {
        this.receiver = receiver;
    }

    @Override
    public void execute() {
        receiver.action();
    }
}

• Invoker.class

package learn19;

public class Invoker {
    private Command command;

    public void setCommand(Command command) {
        this.command = command;
    }

    public void executeCommmand() {
        command.execute();
    }
}

• Main.class

import learn19.*;

public class Main {

    public static void main(String[] args) throws Exception {
        Receiver r = new Receiver();
        ConcreteCommand c = new ConcreteCommand(r);
        Invoker i = new Invoker();
        i.setCommand(c);
        i.executeCommmand();
    }
}

参考资料

• 大话设计模式