IntelliJ IDEA 2016.1 Help

Extracting Hard-Coded String Literals

Having enabled code inspection that highlights hard-coded string literals, you can proceed with extracting these literals into your properties files. For this purpose, IntelliJ IDEA provides special intention action i18nize hard coded string literal.

This section considers two possible ways of accessing resource bundle:

To extract a string literal using java.util.ResourceBundle

  1. Specify resource bundle that will be used to store the extracted literals. In particular, you can add the following statement to your source code:
    private static ResourceBundle <field name> = ResourceBundle.getBundle("<bundle name>");

    For example:

    private static ResourceBundle myBundle = ResourceBundle.getBundle("com.intellij.fontChooser.FontChooser");
  2. Click the highlighted string, press Alt+Enter, and in the list of intention actions choose i18nize hard coded string literal:
  3. In the I18nize Hard Coded String Literal dialog box specify the target properties file, the property key and value, and the resource bundle expression. If the ResourceBundle field has been declared in the source code (as shown in the step 1), IntelliJ IDEA suggests its name by default. If you haven't declared this field in the source code yet, you can still define the desired expression immediately in the dialog box. To do that, enter a valid expression of the ResourceBundle type in the Resource bundle expression field.

    Note that basic code completion works in this field. Type class name, and press Ctrl+Space after period to select method:


    Choose the desired method from the suggestion list, and press Ctrl+Space once more to fill in the parentheses:


    After that, type the package and resource bundle name in quotes:

  4. Click OK. The line with hard-coded string literal is replaced. For example, if the resource bundle has been declared in the source code, the following line will be created:

    If the resource bundle has been defined in the dialog, the result will be:


To extract a string literal using custom resource bundle class

  1. Make sure that redist/annotations.jar archive that resides under your IntelliJ IDEA installation, is added to the module dependencies.
  2. Create a new class in your project, and type the following code:
    import org.jetbrains.annotations.PropertyKey; import org.jetbrains.annotations.NonNls; import java.util.ResourceBundle; import java.text.MessageFormat; public class I18nSupport { @NonNls private static final ResourceBundle bundle = ResourceBundle.getBundle ("com.intellij.FontChooser"); public static String i18n_str (@PropertyKey(resourceBundle ="com.intellij.FontChooser") String key,Object... params){ String value =bundle.getString(key); if (params.length >0) return MessageFormat.format(value, params); return value; } }
  3. In a class that contains hard-coded string, click the highlighted string, press Alt+Enter, and in the list of intention actions choose i18nize hard coded string literal. The I18n-ize String Literal dialog box shows that resource bundle expression is missing:
  4. Click Edit i18n template link. In the File Template dialog box, change the I18nized Expression to point to the method of your custom resource bundle class:

    Click OK to save the updated template and close the dialog box.

  5. In the Preview section of the I18n-ize String Literal dialog box, see the suggested substitution, and click OK. The source code changes:

See Also

Last modified: 13 July 2016