Change .size() == 0 to .isEmpty() for Collections

[kwonyonghyun]

Expected Behavior

• All checks for empty Collections (Lists, Maps, etc.) should use the .isEmpty() method instead of .size() == 0.

Current Behavior

• The current codebase uses .size() == 0 to check if Lists and Maps are empty.

Context

• This issue affects code readability and adherence to Java Collections Framework conventions.
• We are trying to improve code clarity and follow best practices in Java programming.
• Alternatives considered: Keeping the current .size() == 0 checks, but this doesn't align with standard Java conventions.
• No workarounds are necessary as both methods are functionally equivalent for checking emptiness.

Proposed Changes

1. Replace all occurrences of .size() == 0 with .isEmpty() for Collections (Lists, Maps, etc.).
2. Update any related documentation or coding guidelines to reflect this change.

Reasons for the proposed change:

1. Improved readability: .isEmpty() more clearly expresses the intent of checking whether a collection is empty.
2. Adherence to Java Collections Framework conventions: isEmpty() is the standard method for checking if a collection is empty.

Questions

• Is there a specific reason for using size() == 0 instead of isEmpty() in our current codebase?

[kwonyonghyun]

I've submitted PR #15898 to address this issue. I would greatly appreciate if you could review the changes and provide your feedback.
Please take a look at the implementation and let me know if you have any concerns or if there are any reasons why this change might not be feasible.