Win XP下如何成功安装MSSQL企业版

/*
* 状态模式
* 允许对象在内部状态改变时改变它的行为,
* 对象看起来好像修改了它的类
*/
public class StatePettern {

public static void main(String[] args) {
GumballMachine gumballMachine = new GumballMachine(6);

System.out.println(gumballMachine);

gumballMachine.insterQuarter();
gumballMachine.turnCrank();

System.out.println(gumballMachine);

gumballMachine.insterQuarter();
gumballMachine.turnCrank();
gumballMachine.insterQuarter();
gumballMachine.turnCrank();

System.out.println(gumballMachine);
}

}

//管家类,利用组合,将每个状态实现为一个类
class GumballMachine {
State soldOutState;
State noQuarterState;
State hasQuarterState;
State soldState;

State state = soldOutState;
int count = 0;

public GumballMachine(int numberGumballs) {
soldOutState = new SoldOutState(this);
noQuarterState = new NoQuarterState(this);
hasQuarterState = new HasQuarterState(this);
soldState = new SoldState(this);

this.count = numberGumballs;
if (numberGumballs > 0) {
state = noQuarterState;
}
}

public void insterQuarter() {
state.insertQuarter();
}

public void ejectQuarter() {
state.ejectQuarter();
}

public void turnCrank() {
state.turnCrank();
state.dispense();
}

public void setState(State state) {
this.state = state;
}

void releaseBall() {
System.out.println("A gumball comes rolling out the slot....");
if (count != 0) {
count = count - 1;
}
}

public State getNoQuarterState() {
return noQuarterState;
}

public State getHasQuarterState() {
return hasQuarterState;
}

public State getSoldState() {
return soldState;
}

public State getSoldOutState() {
return soldOutState;
}

public int getCount() {
return count;
}

public String toString() {
return "GumballMachine has " + count +" gumballs left";
}
}

//状态的抽象类,包含了各个状态的动作
interface State {
void insertQuarter();

void ejectQuarter();

void turnCrank();

void dispense();
}

//各个状态的具体实现,注意各个状态之间的转化,在不同的状态下,相同的动作会有不同的实现
//每个具体类都包含了一个管家类
class NoQuarterState implements State {
GumballMachine gumballMachine;

public NoQuarterState(GumballMachine gumballMachine) {
this.gumballMachine = gumballMachine;
}

public void insertQuarter() {
System.out.println("You inserted a quarter");
gumballMachine.setState(gumballMachine.getHasQuarterState());
}

public void ejectQuarter() {
System.out.println("You haven't inserted a quarter");
}

public void turnCrank() {
System.out.println("You turned,but there's no quarter");
}

public void dispense() {
System.out.println("You need to pay first");
}
}

class HasQuarterState implements State {
GumballMachine gumballMachine;

public HasQuarterState(GumballMachine gumballMachine) {
this.gumballMachine = gumballMachine;
}

public void insertQuarter() {
System.out.println("You can't insert another quarter");
}

public void ejectQuarter() {
System.out.println("Quarter returned");
gumballMachine.setState(gumballMachine.getNoQuarterState());
}

public void turnCrank() {
System.out.println("You turned....");
gumballMachine.setState(gumballMachine.getSoldState());
}

public void dispense() {
System.out.println("No gumball dispensed");
}

}

class SoldState implements State {
GumballMachine gumballMachine;

public SoldState(GumballMachine gumballMachine) {
this.gumballMachine = gumballMachine;
}

public void insertQuarter() {
System.out.println("Please wait,we're already giving you a gumball");
}

public void ejectQuarter() {
System.out.println("Sorry,you already turned the crank");
}

public void turnCrank() {
System.out.println("Turning twice doesn't get you anther gumball!");
}

public void dispense() {
gumballMachine.releaseBall();
if (gumballMachine.getCount() > 0) {
gumballMachine.setState(gumballMachine.getNoQuarterState());
} else {
System.out.println("Oops,out of gumballs");
gumballMachine.setState(gumballMachine.getSoldOutState());
}
}
}

class SoldOutState implements State {
GumballMachine gumballMachine;

public SoldOutState(GumballMachine gumballMachine) {
this.gumballMachine = gumballMachine;
}

public void insertQuarter() {
System.out.println("You can't insert a quarter,the mechine is sold out");
}

public void ejectQuarter() {
System.out.println("You haven't inserted a quarter");
}

public void turnCrank() {
System.out.println("You turned,but there's no quarter");
}

public void dispense() {
System.out.println("No gumball dispensed");
}
}
本文出自 ““技”忆” 博客，请务必保留此出处http://sophi.blog.51cto.com/340461/66347