jdk1.5新特性5之枚举之枚举类型的应用

一 简单应用

package cn.xy.Enum;

public enum TrafficLamp
{
RED,GREEN,YELLOW;
}

TrafficLamp red = TrafficLamp.RED;
System.out.println(red);
System.out.println(red.name());
System.out.println(red.ordinal());
System.out.println(TrafficLamp.valueOf("YELLOW"));
TrafficLamp[] ts = TrafficLamp.values();
for (TrafficLamp t : ts)
{
System.out.println(t.name());
}

结果

RED
RED
0
YELLOW
RED
GREEN
YELLOW

二 复杂应用

package cn.xy.Enum;

public enum TrafficLampComplex
{

// 元素列表必须放在枚举类的最上面
RED(10)
{
@Override
public TrafficLampComplex nextLamp()
{
return GREEN;
}

@Override
public String getValue()
{
return "红灯，时长" + this.getTime();
}
},
GREEN(10)
{
@Override
public TrafficLampComplex nextLamp()
{
return YELLOW;
}

@Override
public String getValue()
{
return "绿灯，时长" + this.getTime();
}
},
YELLOW(5)
{
@Override
public TrafficLampComplex nextLamp()
{
return YELLOW;
}

@Override
public String getValue()
{
return "黄灯，时长" + this.getTime();
}
};

/**
* 时长
*/
private int time;

TrafficLampComplex()
{
}

TrafficLampComplex(int time)
{
this.time = time;
}

/**
* 下一个灯
* @return
*/
public abstract TrafficLampComplex nextLamp();

/**
* 取值
* @return
*/
public abstract String getValue();

public int getTime()
{
return time;
}

public void setTime(int time)
{
this.time = time;
}

}

TrafficLampComplex tcRed = TrafficLampComplex.RED;
System.out.println(tcRed.nextLamp());
System.out.println(tcRed.getValue());

结果

GREEN
红灯，时长10

三 提示

如果理解该例子有困难，请参看本博客的《jdk1.5新特性5之枚举之模拟枚举类型》