Java 中 x + x 和 2*x 的区别

Question

I was reading the answers to a Leetcode problem: https://leetcode.com/problems/divide-two-integers/ . This problem requires not using multiplication. After reading a few answers, I somehow had a misconception that x+x is better than 2*x in terms of memory and avoiding type overflow. After post the question, I cannot find any evidence to support this statement. Please ignore this question.

---

I saw a common practice in Java is using x + x instead of 2*x especially for int. For example

int x = 1;
x += x;

Instead of

int x = 1;
x = 2*x;

Using

if (a < b + b) {
  ...
}

Instead of

if (a < 2*b) {
  ...
}

Does x + x save slightly more memory than 2*x ?

Answer 1

It seems more like a habit than has any reason to use this convention, unless JVM is more efficient in carrying our + operation than *, which probably is something we can totally ignore