Collection.isEmpty() should be used to test for emptiness

Using Collection.size() to test for emptiness works, but using Collection.isEmpty() makes the code more readable and can be more performant. The time complexity of any isEmpty() method implementation should be O(1) whereas some implementations of size() can be O(n).

Noncompliant Code Example

// Noncompliant
if (myCollection.size() == 0) {
/* ... */
}

Compliant Solution

if (myCollection.isEmpty()) {
/* ... */
}