public static long requirePositive(long val) {
        if (val < 1) {
            throw new IllegalArgumentException(val + IS_NOT_POSITIVE);
        }
        return val;
    }
Returns the given value if it is positive.

@param val to check
@return the given value
@throws IllegalArgumentException if the given value is not positive
common-parent/invariant/src/main/java/com/speedment/common/invariant/LongRangeUtil.java