Java通过名称获取枚举常量
示例
假设我们有一个枚举DayOfWeek：
enum DayOfWeek {
SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY;
}枚举使用内置的静态valueOf()方法进行编译，该静态方法可用于按其名称查找常量：
String dayName = DayOfWeek.SUNDAY.name();
assert dayName.equals("SUNDAY");
DayOfWeek day = DayOfWeek.valueOf(dayName);
assert day == DayOfWeek.SUNDAY;使用动态枚举类型也可以这样做：
Class<DayOfWeek> enumType = DayOfWeek.class; DayOfWeek day = Enum.valueOf(enumType, "SUNDAY"); assert day == DayOfWeek.SUNDAY;
如果指定的枚举不具有名称匹配的常量，则这两种valueOf()方法都将引发IllegalArgumentException。
Guava库提供了一个辅助方法，该方法返回一个Guava以消除显式的异常处理：Enums.getIfPresent()Optional
DayOfWeek defaultDay = DayOfWeek.SUNDAY; DayOfWeek day = Enums.valueOf(DayOfWeek.class, "INVALID").or(defaultDay); assert day == DayOfWeek.SUNDAY;
热门推荐
10 财运虎年祝福语简短语
11 单亲爸爸春节祝福语简短
12 狗狗上厕所训练
13 植物种植祝福语简短
14 翻译考试祝福语朋友简短
15 个人周年庆简短祝福语
16 狗狗怎么训练
17 分别祝福语简短搞笑英文
18 生日广州男生祝福语简短