Is it valid to compare a double with an int in java?

Question

Utilities.getDistance(uni, enemyuni) <= uni.getAttackRange()

Utilities.getDistance returns double and getAttackRange returns int. The above code

Answer 1

Yes, it's valid - it will promote the int to a double before performing the comparison.

See JLS section 15.20.1 (Numerical Comparison Operators) which links to JLS section 5.6.2 (Binary Numeric Promotion).

From the latter:

Widening primitive conversion (§5.1.2) is applied to convert either or both operands as specified by the following rules:

• If either operand is of type double, the other is converted to double.

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