遥控器项目
实现思路
实现类图
再次梳理
代码实现
class RemoteControl:
"""遥控器"""
on_commands: List[Command]
off_commands: List[Command]
def __init__(self):
self.on_commands = []
self.off_commands = []
no_command = NoCommand()
for _ in range(7):
self.on_commands.append(no_command)
self.off_commands.append(no_command)
def set_command(self, slot: int, on_command: Command, off_command: Command):
self.on_commands[slot] = on_command
self.off_commands[slot] = off_command
def on_button_was_pushed(self, slot: int):
self.on_commands[slot].excute()
def off_button_was_pushed(self, slot: int):
self.off_commands[slot].excute()
def __str__(self):
buffer_str = []
for i in range(len(self.on_commands)):
buffer_str.append(
f'[卡槽{i + 1}]{self.on_commands[i].__class__.__qualname__}\t{self.off_commands[i].__class__.__qualname__}')
return "\n".join(buffer_str)
class LightOffCommand(Command):
light: Light
def __init__(self, light: Light):
self.light = light
def excute(self):
self.light.off()
def undo(self):
pass
class StereoOnWithCDCommand(Command):
stereo: Stereo
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.stereo.on()
self.stereo.set_cd()
self.stereo.set_volume(11)
def undo(self):
pass
if __name__ == '__main__':
remote_control = RemoteControl()
living_room_light = Light("Living Room light")
kitchen_light = Light("Kitchen light")
stereo = Stereo("Living Room Stereo")
living_room_light_on = LightOnCommand(living_room_light)
living_room_light_off = LightOffCommand(living_room_light)
kitchen_light_on = LightOnCommand(kitchen_light)
kitchen_light_off = LightOffCommand(kitchen_light)
stereo_on = StereoOnWithCDCommand(stereo)
stereo_off = StereoOffWithCDCommand(stereo)
remote_control.set_command(0, living_room_light_on, living_room_light_off)
remote_control.set_command(1, kitchen_light_on, kitchen_light_off)
remote_control.set_command(2, stereo_on, stereo_off)
print(remote_control)
print()
remote_control.on_button_was_pushed(0)
remote_control.off_button_was_pushed(0)
remote_control.on_button_was_pushed(1)
remote_control.off_button_was_pushed(1)
remote_control.on_button_was_pushed(2)
remote_control.off_button_was_pushed(2)
设计全貌
完整代码
与书上的代码略有不同，整体结构是一样的。书上是吊扇，我这里是音响。
from abc import ABCMeta, abstractmethod, ABC
from typing import List
class Command(ABC):
@abstractmethod
def excute(self):
pass
@abstractmethod
def undo(self):
pass
class NoCommand(Command):
def excute(self):
pass
def undo(self):
pass
class Light:
"""电灯"""
name: str
def __init__(self, name):
self.name = name
def off(self):
print(f'{self.name} is off.')
def on(self):
print(f'{self.name} is on.')
class LightOnCommand(Command):
light: Light
def __init__(self, light: Light):
self.light = light
def excute(self):
self.light.on()
def undo(self):
print('撤销操作，', end='')
self.light.off()
class LightOffCommand(Command):
light: Light
def __init__(self, light: Light):
self.light = light
def excute(self):
self.light.off()
def undo(self):
print('撤销操作，', end='')
self.light.on()
class Stereo:
"""音响"""
name: str
def __init__(self, name):
self.name = name
def off(self):
print(f'{self.name} is off.')
def on(self):
print(f'{self.name} is on.')
def set_cd(self):
print(f'{self.name} is set for CD input.')
def set_volume(self, volume: int):
print(f'{self.name} volume set to {volume}.')
class StereoOnWithCDCommand(Command):
stereo: Stereo
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.stereo.on()
self.stereo.set_cd()
self.stereo.set_volume(11)
def undo(self):
print('撤销操作，', end='')
self.stereo.off()
class StereoOffWithCDCommand(Command):
stereo: Stereo
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.stereo.off()
def undo(self):
print('撤销操作，', end='')
self.stereo.on()
class RemoteControl:
"""遥控器"""
on_commands: List[Command]
off_commands: List[Command]
undo_command: Command
def __init__(self):
self.on_commands = []
self.off_commands = []
no_command = NoCommand()
for _ in range(7):
self.on_commands.append(no_command)
self.off_commands.append(no_command)
self.undo_command = no_command
def set_command(self, slot: int, on_command: Command, off_command: Command):
self.on_commands[slot] = on_command
self.off_commands[slot] = off_command
def on_button_was_pushed(self, slot: int):
self.on_commands[slot].excute()
self.undo_command = self.on_commands[slot]
def off_button_was_pushed(self, slot: int):
self.off_commands[slot].excute()
self.undo_command = self.off_commands[slot]
def undo_button_was_pushed(self):
self.undo_command.undo()
def __str__(self):
buffer_str = []
for i in range(len(self.on_commands)):
buffer_str.append(
f'[卡槽{i + 1}]{self.on_commands[i].__class__.__qualname__}\t{self.off_commands[i].__class__.__qualname__}')
return "\n".join(buffer_str)
if __name__ == '__main__':
remote_control = RemoteControl()
living_room_light = Light("Living Room light")
kitchen_light = Light("Kitchen light")
stereo = Stereo("Living Room Stereo")
living_room_light_on = LightOnCommand(living_room_light)
living_room_light_off = LightOffCommand(living_room_light)
kitchen_light_on = LightOnCommand(kitchen_light)
kitchen_light_off = LightOffCommand(kitchen_light)
stereo_on = StereoOnWithCDCommand(stereo)
stereo_off = StereoOffWithCDCommand(stereo)
remote_control.set_command(0, living_room_light_on, living_room_light_off)
remote_control.set_command(1, kitchen_light_on, kitchen_light_off)
remote_control.set_command(2, stereo_on, stereo_off)
print(remote_control)
print()
remote_control.on_button_was_pushed(0)
remote_control.off_button_was_pushed(0)
remote_control.undo_button_was_pushed()
remote_control.on_button_was_pushed(1)
remote_control.undo_button_was_pushed()
remote_control.off_button_was_pushed(1)
remote_control.off_button_was_pushed(2)
remote_control.on_button_was_pushed(2)
remote_control.undo_button_was_pushed()
"""运行结果：
[卡槽1]LightOnCommand LightOffCommand
[卡槽2]LightOnCommand LightOffCommand
[卡槽3]StereoOnWithCDCommand StereoOffWithCDCommand
[卡槽4]NoCommand NoCommand
[卡槽5]NoCommand NoCommand
[卡槽6]NoCommand NoCommand
[卡槽7]NoCommand NoCommand
Living Room light is on.
Living Room light is off.
撤销操作，Living Room light is on.
Kitchen light is on.
撤销操作，Kitchen light is off.
Kitchen light is off.
Living Room Stereo is off.
Living Room Stereo is on.
Living Room Stereo is set for CD input.
Living Room Stereo volume set to 11.
撤销操作，Living Room Stereo is off.
"""
添加撤销操作
from abc import ABCMeta, abstractmethod, ABC
from typing import List
class Command(ABC):
@abstractmethod
def excute(self):
pass
@abstractmethod
def undo(self):
pass
class NoCommand(Command):
def excute(self):
pass
def undo(self):
pass
class Stereo:
"""音响"""
name: str
HIGH = 90
MEDIUM = 40
LOW = 10
OFF = 0
_volume: int
def __init__(self, name):
self.name = name
self._volume = Stereo.OFF
def off(self):
print(f'{self.name} is off.')
def on(self):
print(f'{self.name} is on.')
def set_cd(self):
print(f'{self.name} is set for CD input.')
def set_volume(self, volume: int):
self._volume = volume
print(f'{self.name} volume set to {volume}.')
def get_volume(self):
return self._volume
def volume_high(self):
print(f'音量设置为{Stereo.HIGH}')
self._volume = Stereo.HIGH
def volume_medium(self):
print(f'音量设置为{Stereo.MEDIUM}')
self._volume = Stereo.MEDIUM
def volume_low(self):
print(f'音量设置为{Stereo.LOW}')
self._volume = Stereo.LOW
class StereoOnWithCDCommand(Command):
stereo: Stereo
pre_volume: int
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.pre_volume = self.stereo.get_volume()
self.stereo.on()
self.stereo.set_cd()
self.stereo.set_volume(Stereo.MEDIUM)
def undo(self):
print('撤销操作，', end='')
class StereoHighVolumeWithCDCommand(Command):
pre_volume: int
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.pre_volume = self.stereo.get_volume()
self.stereo.volume_high()
def undo(self):
print('撤销操作，', end='')
if self.pre_volume == Stereo.HIGH:
self.stereo.volume_high()
elif self.pre_volume == Stereo.MEDIUM:
self.stereo.volume_medium()
elif self.pre_volume == Stereo.LOW:
self.stereo.volume_low()
else:
self.stereo.off()
class StereoLowVolumeWithCDCommand(Command):
pre_volume: int
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.pre_volume = self.stereo.get_volume()
self.stereo.volume_low()
def undo(self):
print('撤销操作，', end='')
if self.pre_volume == Stereo.HIGH:
self.stereo.volume_high()
elif self.pre_volume == Stereo.MEDIUM:
self.stereo.volume_medium()
elif self.pre_volume == Stereo.LOW:
self.stereo.volume_low()
else:
self.stereo.off()
class StereoOffWithCDCommand(Command):
stereo: Stereo
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.stereo.off()
def undo(self):
print('撤销操作，', end='')
self.stereo.on()
class RemoteControlWithUndo:
"""遥控器"""
on_commands: List[Command]
off_commands: List[Command]
undo_command: Command
def __init__(self):
self.on_commands = []
self.off_commands = []
no_command = NoCommand()
for _ in range(7):
self.on_commands.append(no_command)
self.off_commands.append(no_command)
self.undo_command = no_command
def set_command(self, slot: int, on_command: Command, off_command: Command):
self.on_commands[slot] = on_command
self.off_commands[slot] = off_command
def on_button_was_pushed(self, slot: int):
self.on_commands[slot].excute()
self.undo_command = self.on_commands[slot]
def off_button_was_pushed(self, slot: int):
self.off_commands[slot].excute()
self.undo_command = self.off_commands[slot]
def undo_button_was_pushed(self):
self.undo_command.undo()
def __str__(self):
buffer_str = []
for i in range(len(self.on_commands)):
buffer_str.append(
f'[卡槽{i + 1}]{self.on_commands[i].__class__.__qualname__}\t{self.off_commands[i].__class__.__qualname__}')
return "\n".join(buffer_str)
if __name__ == '__main__':
remote_control = RemoteControlWithUndo()
stereo = Stereo('音响')
stereo_off = StereoOffWithCDCommand(stereo)
stereo_high_volume = StereoHighVolumeWithCDCommand(stereo)
stereo_low_volume = StereoLowVolumeWithCDCommand(stereo)
remote_control.set_command(0, stereo_high_volume, stereo_off)
remote_control.set_command(1, stereo_low_volume, stereo_off)
print(remote_control)
remote_control.on_button_was_pushed(0)
remote_control.off_button_was_pushed(0)
remote_control.undo_button_was_pushed()
remote_control.on_button_was_pushed(1)
remote_control.undo_button_was_pushed()
"""运行结果：
[卡槽1]StereoHighVolumeWithCDCommand StereoOffWithCDCommand
[卡槽2]StereoLowVolumeWithCDCommand StereoOffWithCDCommand
[卡槽3]NoCommand NoCommand
[卡槽4]NoCommand NoCommand
[卡槽5]NoCommand NoCommand
[卡槽6]NoCommand NoCommand
[卡槽7]NoCommand NoCommand
音量设置为90
音响 is off.
撤销操作，音响 is on.
音量设置为10
撤销操作，音量设置为90
"""
批量操作
使用宏命令
from abc import ABCMeta, abstractmethod, ABC
from typing import List
class Command(ABC):
@abstractmethod
def excute(self):
pass
@abstractmethod
def undo(self):
pass
class NoCommand(Command):
def excute(self):
pass
def undo(self):
pass
class MacroCommand(Command):
commands: List[Command]
def __init__(self, commands: List[Command]):
self.commands = commands
def excute(self):
for command in self.commands:
command.excute()
def undo(self):
for command in self.commands:
command.undo()
class Light:
"""电灯"""
name: str
def __init__(self, name):
self.name = name
def off(self):
print(f'{self.name} is off.')
def on(self):
print(f'{self.name} is on.')
class LightOnCommand(Command):
light: Light
def __init__(self, light: Light):
self.light = light
def excute(self):
self.light.on()
def undo(self):
print('撤销操作，', end='')
self.light.off()
class LightOffCommand(Command):
light: Light
def __init__(self, light: Light):
self.light = light
def excute(self):
self.light.off()
def undo(self):
print('撤销操作，', end='')
self.light.on()
class Stereo:
"""音响"""
name: str
def __init__(self, name):
self.name = name
def off(self):
print(f'{self.name} is off.')
def on(self):
print(f'{self.name} is on.')
def set_cd(self):
print(f'{self.name} is set for CD input.')
def set_volume(self, volume: int):
print(f'{self.name} volume set to {volume}.')
class StereoOnWithCDCommand(Command):
stereo: Stereo
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.stereo.on()
self.stereo.set_cd()
self.stereo.set_volume(11)
def undo(self):
print('撤销操作，', end='')
self.stereo.off()
class StereoOffWithCDCommand(Command):
stereo: Stereo
def __init__(self, stereo: Stereo):
self.stereo = stereo
def excute(self):
self.stereo.off()
def undo(self):
print('撤销操作，', end='')
self.stereo.on()
class RemoteControl:
"""遥控器"""
on_commands: List[Command]
off_commands: List[Command]
undo_command: Command
def __init__(self):
self.on_commands = []
self.off_commands = []
no_command = NoCommand()
for _ in range(7):
self.on_commands.append(no_command)
self.off_commands.append(no_command)
self.undo_command = no_command
def set_command(self, slot: int, on_command: Command, off_command: Command):
self.on_commands[slot] = on_command
self.off_commands[slot] = off_command
def on_button_was_pushed(self, slot: int):
self.on_commands[slot].excute()
self.undo_command = self.on_commands[slot]
def off_button_was_pushed(self, slot: int):
self.off_commands[slot].excute()
self.undo_command = self.off_commands[slot]
def undo_button_was_pushed(self):
self.undo_command.undo()
def __str__(self):
buffer_str = []
for i in range(len(self.on_commands)):
buffer_str.append(
f'[卡槽{i + 1}]{self.on_commands[i].__class__.__qualname__}\t{self.off_commands[i].__class__.__qualname__}')
return "\n".join(buffer_str)
if __name__ == '__main__':
remote_control = RemoteControl()
living_room_light = Light("Living Room light")
kitchen_light = Light("Kitchen light")
stereo = Stereo("Living Room Stereo")
living_room_light_on = LightOnCommand(living_room_light)
living_room_light_off = LightOffCommand(living_room_light)
kitchen_light_on = LightOnCommand(kitchen_light)
kitchen_light_off = LightOffCommand(kitchen_light)
stereo_on = StereoOnWithCDCommand(stereo)
stereo_off = StereoOffWithCDCommand(stereo)
remote_control.set_command(0, living_room_light_on, living_room_light_off)
remote_control.set_command(1, kitchen_light_on, kitchen_light_off)
remote_control.set_command(2, stereo_on, stereo_off)
party_on_macro = [living_room_light_on, kitchen_light_on, stereo_on]
party_on = MacroCommand(party_on_macro)
party_off = MacroCommand([living_room_light_off, kitchen_light_off, stereo_off])
remote_control.set_command(3, party_on, party_off)
print(remote_control)
print()
print('---Pushing Macro On---')
remote_control.on_button_was_pushed(3)
print()
print('---Pushing Macro Off---')
remote_control.off_button_was_pushed(3)
print()
print('---Pushing Macro Undo---')
remote_control.undo_button_was_pushed()
"""运行结果：
[卡槽1]LightOnCommand LightOffCommand
[卡槽2]LightOnCommand LightOffCommand
[卡槽3]StereoOnWithCDCommand StereoOffWithCDCommand
[卡槽4]MacroCommand MacroCommand
[卡槽5]NoCommand NoCommand
[卡槽6]NoCommand NoCommand
[卡槽7]NoCommand NoCommand
---Pushing Macro On---
Living Room light is on.
Kitchen light is on.
Living Room Stereo is on.
Living Room Stereo is set for CD input.
Living Room Stereo volume set to 11.
---Pushing Macro Off---
Living Room light is off.
Kitchen light is off.
Living Room Stereo is off.
---Pushing Macro Undo---
撤销操作，Living Room light is on.
撤销操作，Kitchen light is on.
撤销操作，Living Room Stereo is on.
"""
命令模式的用途
请求队列、日志请求
总结
