软件模式之状态模式简易电梯调度问题含源码

软件构造第5次实验实验报告班级:学号:姓名:2016年4月20日

一.设计1.本次实验旨在通过对电梯调度控制器系统的模拟来进一步理解和掌握状态模式。首先，我们类比了糖果机的状态图，经过多次的修改，完成了以上的状态图。如图所示，一部电梯的初始状态是IdleState空闲状态，当有人按下上/下楼按钮时，若电梯位于当前楼层，则直接开/关门(OpenOrCloseState)；若电梯位于其他楼层，则需要先运行(RunState)至乘客所在的楼层，当运行至乘客所在楼层，转换至开/关门(OpenOrCloseState)，然后电梯进入空闲状态(IdleState)，当乘客进入电梯后按下电梯内的楼层数字按钮时，电梯进入运行状态(RunState)，将乘客送至所需的楼层。

StateidleStateStateopenOrDownStateStaterunStateStatestateintourrentFloorintdestinationFloorScheduler+numberButtonWasPushed()4-upOrDownButtonWasPushed()A+setState()+setCurrentFloor))+setDestinationFloor()+open()+chse()+getldleStated+getOpenOrCtoseState()Scheduler+numberButtonWasPushed()4-upOrDownButtonWasPushed()A+setState()+setCurrentFloor))+setDestinationFloor()+open()+chse()+getldleStated+getOpenOrCtoseState()+getRunStatef)+getCurrentFIdof()+getDestinationFlDQr()+getState(J+taString()+numberButtonWasPushed()+upOrDownButtonWasPushed()-FarriveStartingl)4-arriveDestination()Schedulerscheduler4-pushUpOrDownButton()+pushNumberButton()Elevatorelevator+numberButtonWasPushed()+upOrDownButtonWasPushed()4-arriveStarting()+arriveDestination()Elevatorelevator+numberButtonWasPushed()+upOrDownButtonWasPushed()4-arriveStanting()+arriveDestination()Elevatorelevator+numberButtonWasPushed()+upOrDownButtonWasPushed()4-arriveStarting()4arriveDestination().基于状态模式的电梯调度控制器系统如上图所示。状态模式，即允许对象在内部状态改变时改变它的行为，对象看起来好像是修改了它的类。在状态模式中，客户不会直接和状态交互，只有Context才会对状态提出请求。.从UML类图中可以看到，我们为电梯类(Elevator)提供了获得各个状态的对象方法，即getIdleState()等，这些方法是用于各个具体状态类来实现状态转换的，如下图所示：publicvoidjpDrDownEuttonWasPushed(intfloor)-[System.out.printIn(riYojpasbedtheUpOrDownButton.ri);if(floor=="已寸己匚口工.自已9口工工.”1口口士【))■[一若电梯位于熊客来自的楼层直接开门elevator.setState(elevator.getOpenOrClosestate());收工氏｛//若电梯当前位于其他楼层,应先运行至乘客所在的楼层elevator.setState(elevator.getRunState());elevator.setDestinationFloor(floor);setState()方法的参数应该是对象而非类，因为可以有多部电梯，而不同电梯同一时刻的状态可能是不同的，为了保证电梯之间的状态不会产生混乱，我们需要在Elevator类中提供能够返回每种状态的对象的方法。二.实现I.State/**状态接口@authorYilia*/publicinterfaceState{voidnumberButtonWasPushed(intfloor);//按下楼层数字按钮(电梯内部)参数为需要到达的楼层voidupOrDownButtonWasPushed(intfloor);//按下上/下按钮(电梯外部)参数表示乘客来自哪一个楼层voidarriveStarting();//到达任务开始的楼层voidarriveDestination();//至九达目的的楼层)2.IdleState/**空闲状态@authorYilia**/publicclassIdleStateimplementsState{Elevatorelevator;//intcurrentFloor;publicIdleState(Elevatorelevator){this.elevator=elevator;)publicvoidnumberButtonWasPushed(intfloor){System.out.println("YoupushedtheNumberButton.");elevator.setState(elevator.getRunState());elevator.setDestinationFloor(floor);)publicvoidupOrDownButtonWasPushed(intfloor){System.out.println("YoupushedtheUpOrDownButton.");if(floor==elevator.getCurrentF100r()){//若电梯位于乘客来自的楼层直接开门elevator.setState(elevator.getOpenOrCloseState());}else{//若电梯当前位于其他楼层，应先运行至乘客所在的楼层elevator.setState(elevator.getRunState());elevator.setDestinationFloor(floor);}}publicvoidarriveStarting(){System.out.println("YouhavetopushtheUpOrDownButton.");}publicvoidarriveDestination(){System.out.println("Thereisnooneintheelevator.");}}3.OpenOrCloseState/***开/关门*@authorYilia**/publicclassOpenOrCloseStateimplementsState{Elevatorelevator;//intfloor;publicOpenOrCloseState(Elevatorelevator){this.elevator=elevator;}publicvoidnumberButtonWasPushed(intfloor){elevator.setState(elevator.getIdleState());}publicvoidupOrDownButtonWasPushed(intfloor){elevator.setState(elevator.getIdleState());}publicvoidarriveStarting(){elevator.setState(elevator.getIdleState());)publicvoidarriveDestination(){elevator.setState(elevator.getIdleState());))4.RunTimeState/***运行状态*@authorYilia**/publicclassRunStateimplementsState{Elevatorelevator;intDestinationFloor;publicRunState(Elevatorelevator){this.elevator=elevator;)publicvoidnumberButtonWasPushed(intfloor){System.out.println("Theelevatorisrunningnow!");)publicvoidupOrDownButtonWasPushed(intfloor){System.out.println("Pleasewaitamunite.");)publicvoidarriveStarting(){elevator.setCurrentF100r(elevator.getDestinationF100r());System.out.println("Theelevatorarriveatthe"+elevator.getCurrentF100r()+"floor.");elevator.setState(elevator.getOpenOrCloseState());elevator.open();//人上电梯elevator.close();)publicvoidarriveDestination(){elevator.setCurrentF100r(elevator.getDestinationF100r());System.out.print1n("Theelevatorarriveatthe"+elevator.getCurrentF100r()+"floor.");elevator.setState(elevator.getOpenOrCloseState());elevator.open();//人下电梯elevator.close();)5.Elevator/**对应GumballMachine@authorYilia**/publicclassElevator//三个状态StateidleState;StateopenOrCloseState;StaterunState;Statestate=idleState;//State实例变量intcurrentFloor=1;//将当前楼层初始化为1楼intdestinationFloor=-1;//将目的楼层初始化为负数//构造器：为每一个状态创建状态实例，默认电梯从1楼publicElevator(){//this.level=level;idleState=newIdleState(this);openOrCloseState=newOpenOrCloseState(this);runState=newRunState(this);state=idleState;)//构造器:取得当前所在的楼层，为每一个状态创建状态实例publicElevator(intfloor){this.currentFloor=floor;idleState=newIdleState(this);openOrCloseState=newOpenOrCloseState(this);runState=newRunState(this);state=idleState;)//将动作委托到当前状态//注意：ArriveStarting()和ArriveDestanation()动作方法是内部的动作，用户不可以直接让电梯到达楼层publicvoidnumberButtonWasPushed(intfloor){state.numberButtonWasPushed(floor);state.arriveDestination();)publicvoidupOrDownButtonWasPushed(intfloor){state.upOrDownButtonWasPushed(floor);state.arriveStarting();)//允许状态对象改变机器的状态voidsetState(Statestate){this.state=state;)voidsetDestinationFloor(intfloor){this.destinationFloor=floor;)voidsetCurrentF100r(intfloor){this.currentFloor=floor;)//开关门voidopen(){System.out.println("Thedoorisopen.");)voidclose(){System.out.println("Thedoorisclose.");)// //到达指定楼层的辅助方法// voidarrive(intfloor){// System.out.println("Theelevatorisgoingtothe"+getF100r()+”floor...");7

//this.floorfloor;//this.floorfloor;// )//GetterpublicStategetIdleState(){returnidleState;)publicStategetOpenOrCloseState(){returnopenOrCloseState;)publicStategetRunState(){returnrunState;)publicintgetCurrentF100r(){returncurrentFloor;)publicintgetDestinationF100r(){returndestinationFloor;)publicStategetState(){returnstate;)//toString()publicStringtoString(){\nCurrentreturn"ELEVATOR\n"+"CurrentFloor:"+getCurrentF100r()+State:"+getState()+"\n";\nCurrent))6.Scheduler/**对应GumballMachine@authorYilia*/publicclassScheduler{Elevatorelevator_1;Elevatorelevator_2;intfloor;publicScheduler(){elevator_1=newElevator();elevator_2=newElevator();)publicElevatorupOrDownButtonWasPushed(){if((elevator_1.getState()==elevator_1.getIdleState())&&(elevator_2.getState()==elevator_2.getIdleState())){//若都空闲，选择离得近的intcha_1=Math.abs(elevator_1.currentFloor-floor);intcha_2=Math.abs(elevator_2.currentFloor-floor);intmin=Math.min(cha_1,cha_2);if(min==cha_1){returnelevator_1;}else{returnelevator_2;}}elseif(elevator_1.getState()==elevator_1.getIdleState()){//1号电梯空闲returnelevator_1;}elseif(elevator_2.getState()==elevator_2.getIdleState()){//2号电梯空闲returnelevator_2;}else{System.out.println("Pleasewait.Allelevatorsarebasy!");returnnull;}}publicElevatorupOrDownButtonWasPushed(intfloor){this.floor=floor;if((elevator_1.getState()==elevator_1.getIdleState())&&(elevator_2.getState()==elevator_2.getIdleState())){//若都空闲，选择离得近的intcha_1=Math.abs(elevator_1.currentFloor-floor);intcha_2=Math.abs(elevator_2.currentFloor-floor);intmin=Math.min(cha_1,cha_2);if(min==cha1){elevator_1.upOrDownButtonWasPushed(floor);returnelevator_1;}else{elevator_2.upOrDownButtonWasPushed(floor);returnelevator_2;}}elseif(elevator_1.getState()==elevator_1.getIdleState()){//1号电梯空闲elevator_1.upOrDownButtonWasPushed(floor);returnelevator_1;}elseif(elevator_2.getState()==elevator_2.getIdleState()){//2号电梯空闲elevator_2.upOrDownButtonWasPushed(floor);returnelevator_2;}else{System.out.println("Pleasewait.Allelevatorsarebasy!");returnnull;}}publicvoidnumberButtonWasPushed(intdestinationFloor){if(upOrDownButtonWasPushed()!=null){upOrDownButtonWasPushed().numberButtonWasPushed(destinationFloor);}else{System.out.println("Pleasewait.Allelevatorsarebasy!");}}}7.PersonpublicclassPerson{Schedulerscheduler;publicPerson(Schedulerscheduler){this.scheduler=scheduler;}voidpushUpOrDownButton(intfloor){scheduler.upOrDownButtonWasPushed(floor);}voidpushNumberButton(intdestination){scheduler.numberButtonWasPushed(destination);;}}108.ClientpublicclassClient{publicstaticvoidmain(String[]aegs){Schedulerscheduler=newScheduler。；Personperson=newPerson(scheduler);person.pushUpOrDownButton(2);person.pushNumberButton(1);))运行结果：生问题叵Javadoc^声明且控制台滉|Client[1][Java A:\Java\jre\bin\javaw.exeYojplanedtneUpOrDownTheelevatorarriveatthe2floor.Thedoorisopen.Thedoorisclose.YojpushedtheNumberButton.Theelevatorarriveatt