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According to the Java API, Class Enum<E extends Enum<E>> [API 2011], Class Enum<E extends Enum<E>>, public final int ordinal()
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The Java Language Specification [JLS 2011], §8.9, "Enums" [JLS 2011], " does not specify the use of ordinal() in programs. However, attaching external significance to the ordinal() value of an enum constant is error prone and should be avoided.
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