Compare Java enum values

Question

Is there a way to check if an enum value is 'greater/equal' to another value?

I want to check if an error level is 'error or above'.

Answer 1

All Java enums implements Comparable: http://java.sun.com/javase/6/docs/api/java/lang/Enum.html

You can also use the ordinal method to turn them into ints, then comparison is trivial.

if (ErrorLevel.ERROR.compareTo(someOtherLevel) <= 0) {   ... } 

Answer 2

A version which is much more expressive would be

myError.isErrorOrAbove(otherError) 

or

myError.isWorseThan(otherError) 

This way you can define the ordering inside the Enum and can change the implementation internally if you like. Now the clients of the Enum can compare values without knowing any details about it.

A possible implementation whould be

public enum ErrorLevel {      INFO(0),     WARN(1),     ERROR(2),     FATAL(3);      private Integer severity;      ErrorLevel(int severity) {         this.severity = severity;     }      public boolean isWorseThan(ErrorLevel other) {         return this.severity > other.severity;     } } 

I also would not recommend using the ordinal() method for comparison, because when somebody changes the order the Enum values are defined you could get unexpected behaviour.