Inspectopedia 2025.2 Help

Single character string argument in 'String.indexOf()' call

Reports single character strings being used as an argument in String.indexOf() and String.lastIndexOf() calls.

A quick-fix is suggested to replace such string literals with equivalent character literals, gaining some performance enhancement.

Example:

return s.indexOf("x");

After the quick-fix is applied:

return s.indexOf('x');

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.

SingleCharacterStringConcatenation
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

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 SingleCharacterStringConcatenation

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

Inspection Details

By default bundled with:

IntelliJ IDEA 2025.2, Qodana for JVM 2025.2,

Last modified: 18 September 2025