'Optional' contains array or collection

Reports java.util.Optional or com.google.common.base.Optional types with an array or collection type parameter.

In such cases, it is more clear to just use an empty array or collection to indicate the absence of result.

Example:

  Optional<List<Integer>> foo() {
    return Optional.empty();
  }

This code could look like:

  List<Integer> foo() {
    return List.of();
  }
  

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OptionalContainsCollection

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This inspection depends on the Java feature 'Stream and Optional API' which is available since Java 8.

Last modified: 18 June 2024