1007cc1b15
Co-authored-by: nicolas-gauthier-sonarsource <121794895+nicolas-gauthier-sonarsource@users.noreply.github.com> Co-authored-by: Fred Tingaud <95592999+frederic-tingaud-sonarsource@users.noreply.github.com>
46 lines
1.3 KiB
Plaintext
46 lines
1.3 KiB
Plaintext
== Why is this an issue?
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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.
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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)`.
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[source,java,diff-id=1,diff-type=noncompliant]
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----
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public class MyClass {
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public void doSomething(Collection<String> myCollection) {
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if (myCollection.size() == 0) { // Noncompliant
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doSomethingElse();
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}
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}
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}
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----
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Prefer using `isEmpty()` to test for emptiness over `size()`.
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[source,java,diff-id=1,diff-type=compliant]
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----
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public class MyClass {
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public void doSomething(Collection<String> myCollection) {
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if (myCollection.isEmpty()) {
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doSomethingElse();
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}
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}
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}
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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include::../message.adoc[]
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'''
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== Comments And Links
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(visible only on this page)
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include::../comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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