String concatenation

Reports String concatenations. Concatenation might be incorrect in an internationalized environment and could be replaced by usages of java.text.MessageFormat or similar classes.

Example:

  String getMessage(String string, int number) {
    return string + number;
  }

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.

StringConcatenation

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 | Internationalization

Inspection ID: StringConcatenation

Inspection options

Here you can find the description of settings available for the String concatenation inspection, and the reference of their default values.

Ignore for assert statement description arguments

Option ID:

ignoreAsserts

Default value:

Not selected

Ignore for 'System.out.print' arguments

Option ID:

ignoreSystemOuts

Default value:

Not selected

Ignore for 'System.err.print' arguments

Option ID:

ignoreSystemErrs

Default value:

Not selected

Ignore for constructor arguments of Throwable subclasses

Option ID:

ignoreThrowableArguments

Default value:

Not selected

Ignore for initializers of constant fields

Option ID:

ignoreConstantInitializers

Default value:

Not selected

Ignore inside toString() methods

Option ID:

ignoreInToString

Default value:

Not selected

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 StringConcatenation

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