Boolean method is always inverted

Last modified: 03 December 2024

Reports methods with a boolean return type that are always negated when called.

A quick-fix is provided to invert and optionally rename the method. For performance reasons, not all problematic methods may be highlighted in the editor.

Example:

class C {
  boolean alwaysTrue() {
    return true;
  }

  void f() {
    if (!alwaysTrue()) {
      return;
    }
  }
  boolean member = !alwaysTrue();
}

After the quick-fix is applied:

class C {
  boolean alwaysFalse() {
    return false;
  }

  void f() {
    if (alwaysFalse()) {
      return;
    }
  }
  boolean member = alwaysFalse();
}

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.

BooleanMethodIsAlwaysInverted
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 | Data flow

Inspection Details

By default bundled with:

IntelliJ IDEA 2024.3, Qodana for JVM 2024.3,

Can be installed with plugin:

Java, 243.23126