Trivial usage of functional expression

Reports functional interface methods calls that are directly invoked on the definition of the lambda, method reference, or anonymous class. Such method calls can be replaced with the body of the functional interface implementation.

Example:

  boolean contains(List<String> names, String name) {
    return ((Predicate<String>)x -> {
      return names.contains(x);
    }).test(name);
  }

When the quick-fix is applied, the method call changes to:

  boolean contains(List<String> names, String name) {
    return names.contains(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.

TrivialFunctionalExpressionUsage

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 | Declaration redundancy

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 TrivialFunctionalExpressionUsage

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