Java enum reverse look-up best practice

Question

I saw it suggested on a blog that the following was a reasonable way to do a \"reverse-lookup\" using the getCode(int) in a Java enum:

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Answer 1

Though it has higher overhead, the static map is nice because it offers constant-time lookup by code. Your implementation's lookup time increases linearly with the number of elements in the enum. For small enums, this simply will not contribute significantly.

One issue with both implementations (and, arguably, with Java enums in general) is that there's really a hidden extra value that a Status can take on: null. Depending on the rules of the business logic, it may make sense to return an actual enum value, or throw an Exception, when the lookup "fails."