That behavior is inherited from C. The pre/post increment behavior is actually the same in every language that uses them. The priority of operation is also usually the same as well.

The reason the question is tricky is because those operators change the value of a as the full expression is progressively executed.

It's not immediately clear to me what the answer in Java would be.

Just take a++ + ++a for example:

If the value if `a` is hoisted by the jvm then it could be 5++ + ++5, so 5 + 6.

But if it's executed left to right and `a` is looked up every time, then it becomes 5++ + ++6, so 5 + 7.