The assignment to variable has no effect?

compiler-warnings, java, post-increment, pre-increment

Solution

`count++` and `++count` are both short for `count=count+1`. The assignment is built in, so there's no point to assigning it again. The difference between `count++` (also knows as postfix) and `++count` (also known as prefix) is that `++count` will happen before the rest of the line, and `count++` will happen after the rest of the line.

If you were to take apart `count=count++`, you would end up with this:

    count = count;
    count = count+1;

Now you can see why postfix won't give you a warning: something is actually being changed at the end.

If you take apart `count=++count`, you would end up with this:

    count = count+1;
    count = count;

As you can see, the second line of code is useless, and that's why the compiler is warning you.

Problem

When I do this: count = ++count; Why do i get the warning - The assignment to variable count has no effect ? This means that count is incremented and then assigned to itself or something else ? Is it the same as just ++count ? What happens in count = count++; ? Why don't I get a warning for this ?

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