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 Details
By default bundled with:	IntelliJ IDEA 2024.2, Qodana for JVM 2024.2,
Can be installed with plugin:	Java, 242.22892

Last modified: 11 September 2024