Can you call equals on null?

Consequently, if both arguments are null, it returns true and if exactly one argument is null, it returns false. Otherwise, it then simply calls the equals() method of the passed argument’s type’s class – which in our case is String’s class equals() method.

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Can null == null?

If you think of it from a programming (i.e. pointer reference) point of view then, yes, two references of null have the same pointer value and, since most of the popular languages will fall back to pointer-equality if no custom equality is defined, null does equal null .

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