new Random().nextInt(999999) sometimes generates 5 digit number [duplicate]

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• Java Generate Random Number Between Two Given Values [duplicate] 7 answers

I am using new Random().nextInt(999999) to generate a 6 digit random number. But sometimes it generates 5 digit numbers. And I explicitly have to check if generated number is not 6 digit.

Why this method does that? And is there any other way to be pretty sure it generate only 6 digit random number.