命令模式

   命令模式：将请求封装成对象，这可以让你使用不同的请求，队列，或者日志请求来参数化其他对象。命令模式也可以支持撤销操作。——《HEAD FIRST 设计模式》

   我的golang代码：

package command

import (
    "fmt"
)

const slotnums = 7

type Command interface {
    execute()
}

/////////////////////////////////////
type RemoteControl struct {
    onCommands  []Command
    offCommands []Command
}

func NewRemoteControl() *RemoteControl {
    r := new(RemoteControl)
    r.onCommands = make([]Command, slotnums, slotnums)
    r.offCommands = make([]Command, slotnums, slotnums)

    return r
}

func (c *RemoteControl) SetCommand(s uint, on Command, off Command) {
    if s >= slotnums {
        return
    }

    c.onCommands[s] = on
    c.offCommands[s] = off
}

func (c *RemoteControl) OnButtonWasPushed(s uint) {
    if s >= slotnums {
        return
    }

    c.onCommands[s].execute()
}

func (c *RemoteControl) OffButtonWasPushed(s uint) {
    if s >= slotnums {
        return
    }

    c.offCommands[s].execute()
}

/////////////////////////////////////
type Light struct {
}

func (c *Light) on() {
    fmt.Println("light is on!")
}

func (c *Light) off() {
    fmt.Println("light is off!")
}

type Stereo struct {
}

func (c *Stereo) on() {
    fmt.Println("stereo is on!")
}

func (c *Stereo) off() {
    fmt.Println("stereo is off!")
}

func (c *Stereo) setCd() {
    fmt.Println("stereo set cd!")
}

func (c *Stereo) setDvd() {
    fmt.Println("stereo set dvd!")
}

func (c *Stereo) setRadio() {
    fmt.Println("stereo set radio!")
}

func (c *Stereo) setVolume() {
    fmt.Println("stereo set volume!")
}

type GarageDoor struct {
}

func (c *GarageDoor) up() {
    fmt.Println("garage door is up!")
}

func (c *GarageDoor) down() {
    fmt.Println("garage door is down!")
}

func (c *GarageDoor) stop() {
    fmt.Println("garage door is stopped!")
}

func (c *GarageDoor) lightOn() {
    fmt.Println("garage door light is on!")
}

func (c *GarageDoor) lightOff() {
    fmt.Println("garage door light is off!")
}

/////////////////////////////////////
type LightOnCommand struct {
    light *Light
}

func NewLightOnCommand(l *Light) *LightOnCommand {
    r := new(LightOnCommand)
    r.light = l

    return r
}

func (c *LightOnCommand) execute() {
    c.light.on()
}

type LightOffCommand struct {
    light *Light
}

func NewLightOffCommand(l *Light) *LightOffCommand {
    r := new(LightOffCommand)
    r.light = l

    return r
}

func (c *LightOffCommand) execute() {
    c.light.off()
}

type StereoOnWithCDCommand struct {
    stereo *Stereo
}

func NewStereoOnWithCDCommand(s *Stereo) *StereoOnWithCDCommand {
    r := new(StereoOnWithCDCommand)
    r.stereo = s

    return r
}

func (c *StereoOnWithCDCommand) execute() {
    c.stereo.on()
    c.stereo.setCd()
    c.stereo.setVolume()
}

type StereoOffCommand struct {
    stereo *Stereo
}

func NewStereoOffCommand(s *Stereo) *StereoOffCommand {
    r := new(StereoOffCommand)
    r.stereo = s

    return r
}

func (c *StereoOffCommand) execute() {
    c.stereo.off()
}

type GarageDoorDownCommand struct {
    garage *GarageDoor
}

func NewGarageDoorDownCommand(g *GarageDoor) *GarageDoorDownCommand {
    r := new(GarageDoorDownCommand)
    r.garage = g

    return r
}

func (c *GarageDoorDownCommand) execute() {
    c.garage.down()
}

type GarageDoorUpCommand struct {
    garage *GarageDoor
}

func NewGarageDoorUpCommand(g *GarageDoor) *GarageDoorUpCommand {
    r := new(GarageDoorUpCommand)
    r.garage = g

    return r
}

func (c *GarageDoorUpCommand) execute() {
    c.garage.up()
}

   个人感悟：待留。