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Comment by bunderbunder | Hacker News Reader

The more worrisome thing about equality in Java is that there are integer values for which

  a == a

is true, while

  a + 1 == a + 1

evaluates to false.

(edit: precision)

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I assume you are referring to the java.lang.Integer box caching situation, which is indeed shitty. However as you've written it, that will always evaluate to true, as it unboxes, adds 1 to each side, and compares the int values, not the references. To get what I assume you are talking about, you need something like:

    Integer b = a+1;
    Integer c = a+1;
    b==c

Which by default returns true for a=126 but false for a=127. A bad situation for sure, but thankfully pretty much every static analysis tool will spot that.

Yes, you're right. Thanks for correction.

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