代碼文件目錄：
文章來源地址http://www.zghlxwxcb.cn/news/detail-631583.html
Command
package Chapter6_CommandPattern.Command;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public interface Command {
public void execute();
public void undo();//撤銷該指令
}
CeilingFan
package Chapter6_CommandPattern.ElectricAppliance;
/**
* @Author 竹心
* @Date 2023/8/6
**/
//吊扇
public class CeilingFan {
public static final int HIGH = 3;
public static final int MEDIUM = 2;
public static final int LOW = 1;
public static final int OFF = 0;
String location;
int speed;
public CeilingFan(String location){
this.location = location;
this.speed = OFF;
}
public void high(){
this.speed = HIGH;
System.out.println(this.location+" ceilingFan is on High");
}
public void medium(){
this.speed = MEDIUM;
System.out.println(this.location+" ceilingFan is on Medium");
}
public void low(){
this.speed = LOW;
System.out.println(this.location+" ceilingFan is on Low");
}
public void off(){
this.speed = OFF;
System.out.println(this.location+" ceilingFan is on Off");
}
public int getSpeed(){
return this.speed;
}
}
CeilingFanHighCommand
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.ElectricAppliance.CeilingFan;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class CeilingFanHighCommand implements Command{
CeilingFan ceilingFan;
int prevSpeed;//保存上一個擋位
public CeilingFanHighCommand(CeilingFan ceilingFan){
this.ceilingFan = ceilingFan;
}
@Override
public void execute() {
this.prevSpeed = this.ceilingFan.getSpeed();
this.ceilingFan.high();
}
@Override
public void undo() {
if(this.prevSpeed==CeilingFan.HIGH){
this.ceilingFan.high();
}else if(this.prevSpeed == CeilingFan.MEDIUM){
this.ceilingFan.medium();
}else if(this.prevSpeed == CeilingFan.LOW){
this.ceilingFan.low();
}else if(this.prevSpeed == CeilingFan.OFF){
this.ceilingFan.off();
}
}
}
Light
package Chapter6_CommandPattern.ElectricAppliance;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class Light {
String name;
public Light(String name){
this.name = name;
}
public void on(){
System.out.println(this.name+" light is on!");
}
public void off(){
System.out.println(this.name+" light is off!");
}
}
LightOnCommand
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.Command.Command;
import Chapter6_CommandPattern.ElectricAppliance.Light;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class LightOnCommand implements Command {
Light light;
public LightOnCommand(Light light){
this.light = light;
}
@Override
public void execute() {
//當(dāng)遙控器運行這個指令的時候，并不知道燈是如何實現(xiàn)打開開關(guān)的
//實現(xiàn)遙控器與電器之間的解耦合
this.light.on();
}
@Override
public void undo() {
this.light.off();
}
}
LightOffCommand
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.ElectricAppliance.Light;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class LightOffCommand implements Command{
Light light;
public LightOffCommand(Light light){
this.light = light;
}
@Override
public void execute() {
this.light.off();
}
public void undo() {
this.light.on();
}
}
GarageDoor
package Chapter6_CommandPattern.ElectricAppliance;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class GarageDoor {
Light light;
public GarageDoor(Light light){
this.light = light;
}
public void up(){
this.lightOn();
System.out.println("the garage door is open!");
}
public void down(){
this.lightOff();
System.out.println("the garage door is closed");
}
private void lightOn(){
this.light.on();
}
private void lightOff(){
this.light.off();
}
}
GarageDoorOpenCommand
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.ElectricAppliance.GarageDoor;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class GarageDoorOpenCommand implements Command{
GarageDoor garageDoor;
public GarageDoorOpenCommand(GarageDoor garageDoor){
this.garageDoor = garageDoor;
}
@Override
public void execute() {
this.garageDoor.up();
}
public void undo() {
this.garageDoor.down();
}
}
GarageDoorCloseCommand
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.ElectricAppliance.GarageDoor;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class GarageDoorCloseCommand implements Command{
GarageDoor garageDoor;
public GarageDoorCloseCommand(GarageDoor garageDoor){
this.garageDoor = garageDoor;
}
@Override
public void execute() {
this.garageDoor.down();
}
public void undo() {
this.garageDoor.down();
}
}
Stereo
package Chapter6_CommandPattern.ElectricAppliance;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class Stereo {
int volume;
//音響類
public void on(){
System.out.println("the stereo is on!");
}
public void off(){
System.out.println("the stereo is off!");
}
public void setCD(){
System.out.println("the stereo can work with CD now!");
}
public void setDVD(){
System.out.println("the stereo can work with DVD now!");
}
public void setVolume(int volume){//設(shè)置音量
this.volume = volume;
}
}
StereoOnWithCDCommand
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.ElectricAppliance.Stereo;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class StereoOnWithCDCommand implements Command{
Stereo stereo;
public StereoOnWithCDCommand(Stereo stereo){
this.stereo = stereo;
}
@Override
public void execute() {
this.stereo.on();
this.stereo.setCD();
this.stereo.setVolume(6);
}
@Override
public void undo() {
this.stereo.off();
}
}
StereoOff
package Chapter6_CommandPattern.Command;
import Chapter6_CommandPattern.ElectricAppliance.Stereo;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class StereoOff implements Command{
Stereo stereo;
public StereoOff(Stereo stereo){
this.stereo = stereo;
}
@Override
public void execute() {
this.stereo.off();
}
public void undo() {
this.stereo.on();
this.stereo.setCD();
this.stereo.setVolume(6);
}
}
MacroCommand
package Chapter6_CommandPattern.Command;
/**
* @Author 竹心
* @Date 2023/8/6
**/
//宏指令
public class MacroCommand implements Command{
Command[] commands;
public MacroCommand(Command[] commands){
this.commands = commands;
}
@Override
public void execute() {
for(int i=0;i<this.commands.length;++i){
this.commands[i].execute();
}
}
@Override
public void undo() {
for(int i=0;i<this.commands.length;++i){
this.commands[i].undo();
}
}
}
NoCommand
package Chapter6_CommandPattern.Command;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class NoCommand implements Command{
@Override
public void execute() {
//this command is useless!
}
@Override
public void undo() {
}
}
RemoteControl
package Chapter6_CommandPattern;
import Chapter6_CommandPattern.Command.Command;
import Chapter6_CommandPattern.Command.NoCommand;
import java.util.Arrays;
/**
* @Author 竹心
* @Date 2023/8/6
**/
//遙控器類
public class RemoteControl {
Command[] onCommands;
Command[] offCommands;
Command undoCommand;
public RemoteControl(){
//為簡潔起見，這里遙控器只有3個槽位
this.onCommands = new Command[7];
this.offCommands = new Command[7];
Command noCommand = new NoCommand();
//這里使用空對象，是為了后面不用寫 if(onCommand[i]==null){...}
for(int i =0;i<7;++i){
this.onCommands[i] = noCommand;
this.offCommands[i] = noCommand;
}
this.undoCommand = noCommand;
}
//設(shè)置某個電器的開關(guān)命令
public void setCommand(int slot, Command onCommand, Command offCommand){
this.onCommands[slot] = onCommand;
this.offCommands[slot] = offCommand;
}
public void onButtonWasPushed(int slot){
this.onCommands[slot].execute();
this.undoCommand = this.onCommands[slot];
}
public void offButtonWasPushed(int slot){
this.offCommands[slot].execute();
this.undoCommand = this.offCommands[slot];
}
public void undoButtonWasPushed(){
this.undoCommand.undo();
}
@Override
public String toString() {
StringBuffer stringBuffer = new StringBuffer();
stringBuffer.append("\n---------- Remote Control ----------\n");
for(int i = 0;i<this.onCommands.length;i++){
stringBuffer.append("[slot "+ i +"] "+
String.format("%-30s",this.onCommands[i].getClass().getSimpleName())+
String.format("%-30s",this.offCommands[i].getClass().getSimpleName())+"\n"
);
}
stringBuffer.append("[undo] "+this.undoCommand.getClass().getSimpleName());
return stringBuffer.toString();
}
}
RemoteLoader
package Chapter6_CommandPattern;
import Chapter6_CommandPattern.Command.*;
import Chapter6_CommandPattern.ElectricAppliance.CeilingFan;
import Chapter6_CommandPattern.ElectricAppliance.GarageDoor;
import Chapter6_CommandPattern.ElectricAppliance.Light;
import Chapter6_CommandPattern.ElectricAppliance.Stereo;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class RemoteLoader {
public static void main(String[] args) {
RemoteControl remoteControl = new RemoteControl();
//創(chuàng)建設(shè)備
Light LivingRoomLight = new Light("LivingRoom");
Light KitchenLight = new Light("Kitchen");
Light GarageLight = new Light("Garage");
GarageDoor garageDoor = new GarageDoor(GarageLight);
Stereo stereo = new Stereo();
//創(chuàng)建命令對象
LightOnCommand livingRoomLightOn =new LightOnCommand(LivingRoomLight);
LightOnCommand kitchenLightOn = new LightOnCommand(KitchenLight);
GarageDoorOpenCommand garageDoorOpenCommand =
new GarageDoorOpenCommand(garageDoor);
StereoOnWithCDCommand stereoOnWithCDCommand =
new StereoOnWithCDCommand(stereo);
LightOffCommand lightOffCommand = new LightOffCommand(LivingRoomLight);
LightOffCommand kitchenLightOff = new LightOffCommand(KitchenLight);
GarageDoorCloseCommand garageDoorCloseCommand =
new GarageDoorCloseCommand(garageDoor);
StereoOff stereoOff = new StereoOff(stereo);
//將命令加載進(jìn)入槽位
remoteControl.setCommand(0,livingRoomLightOn,lightOffCommand);
remoteControl.setCommand(1,kitchenLightOn,kitchenLightOff);
remoteControl.setCommand(2,garageDoorOpenCommand,garageDoorCloseCommand);
remoteControl.setCommand(3,stereoOnWithCDCommand,stereoOff);
//展示
// System.out.println(remoteControl);
remoteControl.onButtonWasPushed(0);
remoteControl.onButtonWasPushed(1);
remoteControl.onButtonWasPushed(2);
remoteControl.onButtonWasPushed(3);
remoteControl.offButtonWasPushed(0);
remoteControl.offButtonWasPushed(1);
remoteControl.offButtonWasPushed(2);
remoteControl.offButtonWasPushed(3);
//使用lambda簡潔編寫代碼
//增加撤銷按鈕后就不能使用了
//這樣就不用寫一大堆命令類了
// remoteControl.setCommand(4,()->LivingRoomLight.on(),
// ()->LivingRoomLight.off());
//測試撤銷功能
System.out.println("\n測試撤銷：");
remoteControl.onButtonWasPushed(0);
remoteControl.undoButtonWasPushed();
//測試風(fēng)扇
System.out.println("test fan");
CeilingFan ceilingFan = new CeilingFan("livingRoom");
CeilingFanHighCommand command = new CeilingFanHighCommand(ceilingFan);
remoteControl.setCommand(4,command,command);
System.out.println(remoteControl);
remoteControl.onButtonWasPushed(4);
System.out.println(remoteControl);
remoteControl.undoButtonWasPushed();
//測試宏指令
System.out.println("\n宏指令");
Light light1 = new Light("Room1");
Light light2 = new Light("Room2");
Light light3 = new Light("Room3");
Light light4 = new Light("Room4");
LightOnCommand lightOnCommand1 = new LightOnCommand(light1);
LightOnCommand lightOnCommand2 = new LightOnCommand(light2);
LightOnCommand lightOnCommand3 = new LightOnCommand(light3);
LightOnCommand lightOnCommand4 = new LightOnCommand(light4);
LightOffCommand lightOffCommand1 = new LightOffCommand(light1);
LightOffCommand lightOffCommand2 = new LightOffCommand(light2);
LightOffCommand lightOffCommand3 = new LightOffCommand(light3);
LightOffCommand lightOffCommand4 = new LightOffCommand(light4);
Command[] onCommands = {lightOnCommand1,lightOnCommand2,lightOnCommand3,lightOnCommand4};
Command[] offCommand = {lightOffCommand1,lightOffCommand2,lightOffCommand3,lightOffCommand4};
MacroCommand partyOn = new MacroCommand(onCommands);
MacroCommand partyOff = new MacroCommand(offCommand);
remoteControl.setCommand(5,partyOn,partyOff);
System.out.println(remoteControl);
remoteControl.onButtonWasPushed(5);
remoteControl.offButtonWasPushed(5);
remoteControl.undoButtonWasPushed();
}
}
SimpleRemoteControl
package Chapter6_CommandPattern;
import Chapter6_CommandPattern.Command.Command;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class SimpleRemoteControl {
Command slot;//目前該遙控器只支持一個槽位
public SimpleRemoteControl(){}
public void setCommand(Command command){
this.slot = command;
}
public void buttonWasPressed(){
this.slot.execute();
}
}
RemoteControlTest
package Chapter6_CommandPattern;
import Chapter6_CommandPattern.Command.GarageDoorOpenCommand;
import Chapter6_CommandPattern.ElectricAppliance.GarageDoor;
import Chapter6_CommandPattern.ElectricAppliance.Light;
/**
* @Author 竹心
* @Date 2023/8/6
**/
public class RemoteControlTest {
public static void main(String[] args) {
SimpleRemoteControl remote = new SimpleRemoteControl();
Light light = new Light("garage light");
GarageDoor garageDoor = new GarageDoor(light);
GarageDoorOpenCommand garageDoorOpen = new GarageDoorOpenCommand(garageDoor);
remote.setCommand(garageDoorOpen);
remote.buttonWasPressed();
}
}
notes.txt
命令模式：
把請求封裝成為對象，以便對不同的請求、隊列或者日志請求來參數(shù)化對象，
并支持可撤銷的操作
命令對象只暴露一個方法：execute()，命令的請求者不會知道執(zhí)行者具體如何實現(xiàn)指令
當(dāng)需要將發(fā)出請求的對象和能夠?qū)嵭姓埱蟮膶ο蠼怦詈系臅r候可以使用命令模式文章來源：http://www.zghlxwxcb.cn/news/detail-631583.html
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