Idempotent loop body

Reports loops whose second and all subsequent iterations do not produce any additional side effects other than the one produced by the first iteration, which can indicate a programming error.

Such loops may iterate only zero, one, or infinite number of times. If the infinite number of times case is unreachable, such a loop can be replaced with an if statement. Otherwise, there's a possibility that the program can get stuck.

Example:

    public void foo(String baseName, String names) {
        int suffix = 1;
        String name = baseName;
        while (names.contains(name)) {
            // error: suffix is not updated making loop body idempotent
            name = baseName + suffix;
        }
    }

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.

IdempotentLoopBody

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 | Control flow issues

New in 2018.1

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