IntelliJ IDEA 2024.1 Help

Hard-coded string literals

If your source code contains hard-coded string literals, you can enable the Internationalization code inspections to highlight them. You can then extract those strings into properties files for localization or ignore them if they are not meant to be localized.

Enable highlighting of hard-coded string literals

  1. Open the Settings dialog Ctrl+Alt+S, expand Editor and click Inspections.

  2. Select the desired profile, and under Java, locate the node Internationalization.

  3. Enable the Hardcoded strings inspection to highlight hard-coded string literals in the editor.

  4. Apply the changes and close the dialog.

Now the editor will highlight hard-coded string literals, as shown in the screenshot below:

Highlighted hard-coded string literal

Internationalize Hardcoded String dialog

IntelliJ IDEA provides a special intention action i18nize hard coded string literal to extract string literals into your properties files. You can access the resource bundle using either the java.util.ResourceBundle class or a custom utility class.



Properties file

In this field, specify an existing .properties file to store the extracted string literal. Type the path to the file manually or click Browse the Browse button to open the Choose Properties File dialog, where you can select the desired location using the project tree view or through a search by name.

Update all properties files in resource bundle

Select this checkbox to have all properties files in the target bundle updated.

Property key

By default, this field displays the suggested key name, based on the value of the string to be extracted. Keep the default name or type the desired one.

Property value

By default, this field displays the value of the string to be extracted. Keep the default value or type the desired one.

Resource bundle expression

By default, this field displays a resource bundle expression from the resource bundle declaration in the source code. If the resource bundle is not declared in the source code, the field does not appear. To define the desired expression, do one of the following:

Edit i18n template

Click this link to open the Edit File Template dialog, where you can change the I18nized Expression template to point to the method of a custom utility class that will be used to access a resource bundle. For more information, refer to Edit the internationalized expression template.

A changed file template is a global setting that affects all projects. If you want to restore defaults, open the File and Code Templates dialog, find the I18nized Expression template in the Code tab, and click the Reset button .


This read-only field displays the results of applying the I18nize hard-coded string literal intention action.

Extracting hard-coded string literals

Extract a string literal using java.util.ResourceBundle

  1. First, you must have at least one properties file in your project, for example, my .properties.

  2. In your source code, specify the resource bundle that will be used to store the extracted literals in the following form:

    private static ResourceBundle <field name> = ResourceBundle.getBundle("<bundle name>");

    For example:

    private static ResourceBundle myBundle = ResourceBundle.getBundle("awesomeBundle");
  3. Click the highlighted string, press Alt+Enter and select i18nize hard coded string literal. In this example, we are using the optional sample code included when you create a new Java project using IntelliJ IDEA.

    Intention action for hard-coded string literals
  4. In the Internationalize Harcoded String dialog, specify an existing target properties file, the key and value of the property, and the resource bundle expression.

    If the ResourceBundle field has been declared in the source code, IntelliJ IDEA suggests its name by default. If you haven't declared this field in the source code, this field won't appear. You must include an expression of the ResourceBundle type in your source code.

    The Internationalize Hardcoded String dialog
  5. Click OK. The line with the hard-coded string literal is replaced.

    • If the resource bundle has been declared in the source code:

    • If the resource bundle has been defined in the dialog:


Edit the internationalized expression template

If you want to access a resource bundle using a custom utility class, you may define the I18nized Expression template either via your settings or the Internationalize Harcoded String dialog to point to the method of your custom utility class.

  • Open the Settings dialog Ctrl+Alt+S, then go to Editor | File and Code Templates | Code | I18ized Expression. Here you can edit the template.

    Edit I18nized Expression template
  • In the Internationalize Harcoded String dialog, select Edit i18n template. In the File Templates dialog, change the I18nized Expression to point to the method of your custom utility class.

    Edit File Templates dialog

Ignoring hard-coded string literals

If you want to ignore a hard-coded string literal, use the Not requiring internationalization annotation.

  1. Press Alt+Enter to show the intention actions for the string literal.

  2. Select Annotate field 'out' as '@NonNls' from the list of actions.

  3. Specify the location where you would like to store the annotations.xml file.

Last modified: 28 June 2024