KITFORMA · EDITORIAL ANSWER
Why does assigning an int multiplication to long still overflow?
KitForma editorial guide. The destination type does not necessarily change how the expression is evaluated. Two int operands can overflow before the result is widened.
Step-by-step answer
The destination type does not necessarily change how the expression is evaluated. Two int operands can overflow before the result is widened.
For a byte estimate, use
long bytes = (long) rows * columns; so widening happens before multiplication. If both values are already long and exceeding the range is an error, use Math.multiplyExact and handle its ArithmeticException as invalid capacity rather than retrying an allocation. Validate negative dimensions separately.
Test an ordinary product and a pair whose product exceeds Integer.MAX_VALUE. Verify the computed value before converting it back or passing it into an int-sized API. A long total still does not guarantee that memory is available, and Java arrays retain their own indexing limitations.Sources and verification
Sources checked:
Scope: This editorial guide is based on the cited sources and tool behavior. A forum question or a query observed for our site does not establish market search volume, low competition, guaranteed rankings or inadequate answers elsewhere.
This editorial answer was prepared by KitForma with AI assistance. It is not presented as a real member question or an independent user review. Check the sources and the result with your own file; report corrections in the discussion.