== Why is this an issue? When you call `isEmpty()`, it clearly communicates the code's intention, which is to check if the collection is empty. Using `size() == 0` for this purpose is less direct and makes the code slightly more complex. Moreover, depending on the implementation, the `size()` method can have a time complexity of `O(n)` where `n` is the number of elements in the collection. On the other hand, `isEmpty()` simply checks if there is at least one element in the collection, which is a constant time operation, `O(1)`. [source,java,diff-id=1,diff-type=noncompliant] ---- public class MyClass { public void doSomething(Collection myCollection) { if (myCollection.size() == 0) { // Noncompliant doSomethingElse(); } } } ---- Prefer using `isEmpty()` to test for emptiness over `size()`. [source,java,diff-id=1,diff-type=compliant] ---- public class MyClass { public void doSomething(Collection myCollection) { if (myCollection.isEmpty()) { doSomethingElse(); } } } ---- ifdef::env-github,rspecator-view[] ''' == Implementation Specification (visible only on this page) include::../message.adoc[] ''' == Comments And Links (visible only on this page) include::../comments-and-links.adoc[] endif::env-github,rspecator-view[]