Functional expression can be folded

Reports method references or lambda expressions that point to a method of their own functional interface type and hence can be replaced with their qualifiers removing unnecessary object allocation.

Example:

  SwingUtilities.invokeLater(r::run);
  SwingUtilities.invokeAndWait(() -> r.run());

After the quick-fix is applied:

  SwingUtilities.invokeLater(r);
  SwingUtilities.invokeAndWait(r);

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.

FunctionalExpressionCanBeFolded

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

This inspection reports only if the language level of the project or module is 8 or higher.

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 FunctionalExpressionCanBeFolded

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