'Optional' used as field or parameter type

Reports any cases in which java.util.Optional<T>, java.util.OptionalDouble, java.util.OptionalInt, java.util.OptionalLong, or com.google.common.base.Optional are used as types for fields or parameters.

Optional was designed to provide a limited mechanism for library method return types in which a clear way to represent "no result" was needed.

Using a field with the java.util.Optional type is also problematic if the class needs to be Serializable, as java.util.Optional is not serializable.

Example:

  class MyClass {
    Optional<String> name; // Optional field

    // Optional parameter
    void setName(Optional<String> name) {
      this.name = name;
    }
  }

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

OptionalUsedAsFieldOrParameterType

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Java | Abstraction issues

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection OptionalUsedAsFieldOrParameterType

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.2

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.2, Qodana for JVM 2025.2,

Last modified: 18 September 2025