Tail recursion

Reports tail recursion, that is, when a method calls itself as its last action before returning.

Tail recursion can always be replaced by looping, which will be considerably faster. Some JVMs perform tail-call optimization, while others do not. Thus, tail-recursive solutions may have considerably different performance characteristics on different virtual machines.

Example:

  int factorial(int val, int runningVal) {
    if (val == 1) {
      return runningVal;
    } else {
      return factorial(val - 1, runningVal * val);
    }
  }

After the quick-fix is applied:

  int factorial(int val, int runningVal) {
    while (true) {
      if (val == 1) {
        return runningVal;
      } else {
        runningVal = runningVal * val;
        val = val - 1;
      }
    }
  }

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.

TailRecursion

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 | Performance

Inspection ID: TailRecursion

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 TailRecursion

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

IntelliJ IDEA 2025.3

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.3, Qodana for JVM 2025.3,

Last modified: 03 December 2025