Comparing Java enum members: == or equals()?

java enums
Matt Ball picture Matt Ball · Nov 17, 2009 · Viewed 713.7k times · Source

I know that Java enums are compiled to classes with private constructors and a bunch of public static members. When comparing two members of a given enum, I've always used .equals(), e.g.

public useEnums(SomeEnum a)
{
    if(a.equals(SomeEnum.SOME_ENUM_VALUE))
    {
        ...
    }
    ...
}

However, I just came across some code that uses the equals operator == instead of .equals():

public useEnums2(SomeEnum a)
{
    if(a == SomeEnum.SOME_ENUM_VALUE)
    {
        ...
    }
    ...
}

Which operator is the one I should be using?

Answer

Reverend Gonzo picture Reverend Gonzo · Nov 17, 2009

Both are technically correct. If you look at the source code for .equals(), it simply defers to ==.

I use ==, however, as that will be null safe.

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