Java enum

使用enum可以方便的替代常量类。

/**enum可以单独定义*/
public enum Week {
	SUNDAY,MONDAY,TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY
}

public class ENUMTest {
	/**enum也可以定义在class里面*/
	public enum Color{RED,ORANGLE,YELLO,GREEN,CYAN,BLUE,PURPLE}
	
	public static void main(String[] args){		
		for(Week w:Week.values()){
         /**ordinal()可以输出索引位置,第一个是0*/
			System.out.print(w+":"+w.ordinal()+", ");
		}
		System.out.println();
		for(Week w:EnumSet.range(Week.MONDAY,Week.SATURDAY)){
			System.out.print(w+":"+w.ordinal()+", ");
		}
		System.out.println();
		for(Color c:Color.values()){
			System.out.print(c+":"+c.ordinal()+", ");
		}
		System.out.println(Color.BLUE);
	}
}