What is the difference between i+=d and i=i+d in Java?

Question

java += question

Why aren’t op-assign operators type safe in java?

When i is an integer and d is a double, i+=d works but i= i+d does not.

Why is this?

Duplicate of http://stackoverflow.com/questions/608721/java-question. — Michael Myers, Mar 06 '09 at 20:43
And this: http://stackoverflow.com/questions/590868/why-arent-op-assign-operators-type-safe-in-java — mtruesdell, Mar 06 '09 at 20:44

score 1 · Answer 1 · answered Mar 06 '09 at 20:43

i = i + d does not work because you would be assigning a double to an int and that is not allowed.

The += operator casts the double automatically to an int, so that is why it works.

1 Answers1