What is x after "x = x++"?

The Java behind the magic

What actually grinds the gears behind x = x++? It's the sequential play of temporary variable creation, the incrementation of x, and assignment of the old value back to x.

int tmp = x; // Stage 1: temp variable holds the original value 
x++; // Stage 2: x is incremented
x = tmp; // Stage 3: original value takes over 
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After this sequence of operations, x still remains at the origin, never really moving an inch.

Dispelling the illusions

The statement x = x++ often gives the illusion that x would be incremented by one. But understanding the intricacies of post-increment operator saves from such misconceptions. To prevent code misinterpretation, it's ideal to separate using the assignment and post-increment on the same variable.

Bypassing the hurdles

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Pre-increment operator

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Opt for pre-increment (++x), which increments x before its value is called upon - pretty straightforward! In such scenarios where x = x++; is accidentally used, x++; or ++x; stands as an apt replacement.

int x = 5;
++x; // Abracadabra: x transforms to 6!
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Code checkers

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Utilize static analysis tools and IDE warnings effectively; they often raise a flag against x = x++;, labeling it as suspicious. Taking such warnings seriously can steer you clear of muddy waters and lead you towards cleaner code.

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Consistent behavior

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Java, with its disciplined habits, doesn't vary the behavior of x = x++; between platforms. It's an intentional design and not some quirky luck of the draw.

Piecing the puzzle together

The mystery of x = x++ can be an entry point to studying Java expressions in more detail. The post-increment operation is firmly defined in the JLS (Java Language Specification), setting a clear path for understanding the behavior of similar expressions in Java.

Pushing the learning curve

Embracing programming puzzles and challenges around Java can help you crack down on these intricate behaviors. When you stumble upon code using x = x++, refactoring it to idiomatic expressions will not only improve your skills but enhance the readability of the code as well.

Addendum

In Java, the nitty-gritty of post-increment operation is well-defined, unlike languages like C, where "x = x++;" could result in undefined, and sometimes even compiler-dependent behavior leading to unpredictable results.