abstract class Command {public abstract void execute();
}

public class MinimizeCommand extends Command {private WindowHanlder whObj; //维持对请求接收者的引用public MinimizeCommand() {whObj = new WindowHanlder();}//命令执行方法，将调用请求接收者的业务方法public void execute() {whObj.minimize();}
}

public class HelpCommand extends Command {private HelpHandler hhObj; //维持对请求接收者的引用public HelpCommand() {hhObj = new HelpHandler();}//命令执行方法，将调用请求接收者的业务方法public void execute() {hhObj.display();}
}

public class HelpHandler {public void display() {System.out.println("显示帮助文档！");}}

public class WindowHanlder {public void minimize() {System.out.println("将窗口最小化至托盘！");}}

public class FunctionButton {private String name; //功能键名称private Command command; //维持一个抽象命令对象的引用public FunctionButton(String name) {this.name = name;}public String getName() {return this.name;}//为功能键注入命令public void setCommand(Command command) {this.command = command;}//发送请求的方法public void onClick() {System.out.print("点击功能键：");command.execute();}
}

public class FBSettingWindow {private String title; //窗口标题//定义一个ArrayList来存储所有功能键private ArrayList<FunctionButton> functionButtons = new ArrayList<FunctionButton>();public FBSettingWindow(String title) {this.title = title;}public void setTitle(String title) {this.title = title;}public String getTitle() {return this.title;}public void addFunctionButton(FunctionButton fb) {functionButtons.add(fb);}public void removeFunctionButton(FunctionButton fb) {functionButtons.remove(fb);}//显示窗口及功能键public void display() {System.out.println("显示窗口：" + this.title);System.out.println("显示功能键：");for (Object obj : functionButtons) {System.out.println(((FunctionButton)obj).getName());}System.out.println("------------------------------");}}

public class client {public static void main(String[] args) {FBSettingWindow fbsw = new FBSettingWindow("功能键设置");FunctionButton fb1,fb2;fb1 = new FunctionButton("功能键1");fb2 = new FunctionButton("功能键1");Command command1,command2;//通过读取配置文件和反射生成具体命令对象command1 = new HelpCommand();command2 = new MinimizeCommand();//将命令对象注入功能键
        fb1.setCommand(command1);fb2.setCommand(command2);fbsw.addFunctionButton(fb1);fbsw.addFunctionButton(fb2);fbsw.display();//调用功能键的业务方法
        fb1.onClick();fb2.onClick();}}