一個Java狀態機樣例的代碼
在UML當中有狀態機視圖,這個狀態機可以用于自動售貨機,自動售票機等等場景,下面是用java代碼模擬的一個狀態機:
1.狀態機接口
package stateMachine; /** * 狀態機接口 * @author seacean * @date 2013-8-29 */ public interface State { /** * 投入硬幣 */ void insertQuarter(); /** * 根據搖動情況,處理搖動結果,返回處理結果,釋放糖果 */ void ejectQuarter(); /** * 轉動搖柄 */ void turnCrank(); /** * 機器放出糖果,處理機器內部狀態,返回初始可投幣狀態 */ void dispense(); } |
2.帶有狀態機的機器
package stateMachine; /** * 機器類,包含多種狀態,處理流程 * @author seacean * @date 2013-8-29 */ public class Machine { //機器本身包含所有的狀態機 private State soldOutState; private State noQuarterState; private State hasQuarterState; private State soldState; private State state; //機器的當前狀態 private int count = 0;//機器中當前糖果的數量 /** * 初始化機器,引入所有的狀態機,初始化糖果數量,初始化機器狀態 * @param count */ public Machine(int count) { this.soldOutState = new SoldOutState(this); this.noQuarterState = new NoQuarterState(this); this.hasQuarterState = new HasQuarterState(this); this.soldState = new SoldState(this); this.count = count; if (this.count > 0) { this.state = noQuarterState; } } /** * 釋放糖果時的內部處理程序 */ public void releaseBall() { System.out.println("a gumball comes rolling out the solt..."); if (count > 0) { count -= 1; } } public void insertQuerter() { state.insertQuarter();//加入硬幣 } public void ejectQuarter() { state.ejectQuarter(); } public void turnCrank() { state.turnCrank(); state.dispense(); } public State getSoldOutState() { return soldOutState; } public State getNoQuarterState() { return noQuarterState; } public State getHasQuarterState() { return hasQuarterState; } public State getSoldState() { return soldState; } public State getState() { return state; } public int getCount() { return count; } public void setState(State state) { this.state = state; } } |
3.下面是狀態機的一些實現類
package stateMachine; /** * 機器處于沒有投硬幣的狀態 * @author seacean * @date 2013-8-29 */ public class NoQuarterState implements State { private Machine machine; public NoQuarterState(Machine machine) { this.machine = machine; } @Override public void insertQuarter() { System.out.println("please insert a quarter!"); machine.setState(machine.getHasQuarterState()); } @Override public void ejectQuarter() { System.out.println("please insert a quarter!"); } @Override public void turnCrank() { System.out.println("please insert a quarter!"); } @Override public void dispense() { System.out.println("please insert a quarter!"); } } |
package stateMachine; /** * 機器處于有硬幣,有糖果,沒有搖動的狀態 * @author seacean * @date 2013-8-29 */ public class HasQuarterState implements State { private Machine machine; public HasQuarterState(Machine machine){ this.machine=machine; } @Override public void insertQuarter() { System.out.println("You can not insert another quarter!"); } @Override public void ejectQuarter() { System.out.println("Quarter returned!"); machine.setState(machine.getNoQuarterState()); } @Override public void turnCrank() { System.out.println("You turned ... "); machine.setState(machine.getSoldState()); } @Override public void dispense() { System.out.println("No gumball dispensed!"); } } |
package stateMachine; /** * 機器正在出售糖果的狀態 * * @author seacean * @date 2013-8-29 */ public class SoldState implements State { private Machine machine; public SoldState(Machine machine) { this.machine = machine; } @Override public void insertQuarter() { System.out.println("please wait,we are already giving you a gumball!"); } @Override public void ejectQuarter() { System.out.println("Sorry, you have turned the crank!"); } @Override public void turnCrank() { System.out.println("Turning twice does not get you another gumball!"); } @Override public void dispense() { machine.releaseBall(); if (machine.getCount() > 0) { machine.setState(machine.getNoQuarterState()); } else { System.out.println("Out of Gumballs!"); machine.setState(machine.getSoldOutState()); } } } |
package stateMachine; /** * 機器處于無糖果狀態 * @author seacean * @date 2013-8-29 */ public class SoldOutState implements State { private Machine machine; public SoldOutState(Machine machine) { this.machine=machine; } @Override public void insertQuarter() { System.out.println("Sorry, there is no gumball in the machine!"); } @Override public void ejectQuarter() { System.out.println("Sorry, there is no gumball in sold!"); } @Override public void turnCrank() { System.out.println("Sorry, there is no gumball!Turn is no meaning."); machine.setState(machine.getNoQuarterState()); } @Override public void dispense() { System.out.println("Sorry, there is no gumball!"); } } |
4.下面是測試類
package stateMachine; //測試類 public class StateMachineTest { public static void main(String[] args) { Machine machine=new Machine(10); for(int i=0;i<11;i++){ System.out.println(machine); machine.insertQuerter(); machine.turnCrank(); } } } |
posted on 2014-07-02 16:37 順其自然EVO 閱讀(296) 評論(0) 編輯 收藏 所屬分類: 測試學習專欄