The Wren Security I18N Framework for Java provides an easy to use type safe API for obtaining localizable messages.

Getting started

In order to get started using this framework you should first define some localized messages in property files and locate these in your resource directory. For example, consider the following simple properties files:

src/main/resources/com/example/myapp/core.properties

    MESSAGE_WITH_NO_ARGS=Message with no args
    MESSAGE_WITH_STRING=Arg1=%s
    MESSAGE_WITH_STRING_AND_NUMBER=Arg1=%s Arg2=%d

src/main/resources/com/example/myapp/core_fr.properties

    MESSAGE_WITH_NO_ARGS=French message with no args
    MESSAGE_WITH_STRING=French Arg1=%s
    MESSAGE_WITH_STRING_AND_NUMBER=French Arg1=%s Arg2=%d

Once you have your property files defined you can use the i18n-maven-plugin to generate the messages. To do this, add the following lines to your pom.xml:

  <build>
    <plugins>
      <plugin>
        <groupId>org.wrensecurity.commons</groupId>
        <artifactId>i18n-maven-plugin</artifactId>
        <version>${project.version}</version>
        <executions>
          <execution>
            <phase>generate-sources</phase>
            <goals>
              <goal>generate-messages</goal>
            </goals>
            <configuration>
              <messageFiles>
                <messageFile>com/example/myapp/core.properties</messageFile>
              </messageFiles>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>

This will generate a Java file in target/generated-sources/messages/com/example/myapp/CoreMessages.java containing LocalizableMessageDescriptors for each message contained in the property file. For example:

  public final class CoreMessages {
    ...

    /**
    * Message with no args
    */
    public static final LocalizableMessageDescriptor.Arg0 MESSAGE_WITH_NO_ARGS =
            new LocalizableMessageDescriptor.Arg0(CoreMessages.class,RESOURCE,"MESSAGE_WITH_NO_ARGS",-1);

    /**
    * Arg1=%s
    */
    public static final LocalizableMessageDescriptor.Arg1<CharSequence> MESSAGE_WITH_STRING =
            new LocalizableMessageDescriptor.Arg1<CharSequence>(CoreMessages.class,RESOURCE,"MESSAGE_WITH_STRING",-1);

    /**
    * Arg1=%s Arg2=%d
    */
    public static final LocalizableMessageDescriptor.Arg2<CharSequence,Number> MESSAGE_WITH_STRING_AND_NUMBER =
            new LocalizableMessageDescriptor.Arg2<CharSequence,Number>(CoreMessages.class,RESOURCE,"MESSAGE_WITH_STRING_AND_NUMBER",-1);

  }

To use the generated messages you'll need the following dependency:

  <groupId>org.wrensecurity.commons</groupId>
  <artifactId>i18n-core</artifactId>
  <version>${project.version}</version>
  <scope>compile</scope>

Messages can then be instantiated in a type safe manner which is enforced at compile time (unlike CAL10N) as well as avoiding runtime errors due to missing properties (CAL10N has this too):

  LocalizableMessage m = MESSAGE_WITH_STRING_AND_NUMBER.get("a string", 123);
  String s1 = m.toString(); // Default locale.
  String s2 = m.toString(Locale.FRENCH);

  // Using SLF4J support: using logger "com.example.mayapp.core" and default locale.
  LocalizedLogger logger = LocalizedLoggerFactory.getInstance(CoreMessages.resourceName());
  logger.error(MESSAGE_WITH_STRING_AND_NUMBER, "a string", 123);

Note that it is also possible to associated an ordinal with each message by appending a number to the end of the property name. For example, the following message will have the ordinal 389:

src/main/resources/com/example/myapp/core.properties
```
MESSAGE_WITH_ORDINAL_389=Message with ordinal
```

The ordinal can be retrieved by calling the method LocalizableMessage.ordinal(). This allows each message to be uniquely identified by its ordinal and its resource name (e.g. "com.example.mayapp.core"), the latter being obtained by calling the method LocalizableMessage.resourceName() which is also available in each generated message file. The ability to uniquely identify log messages is useful when diagnosing log messages which have been output in a locale that you don't understand.

Packages

Package

Description

org.forgerock.i18n

A common framework for embedding localizable messages in applications.

Wren Security I18N Core 23.0.0-SNAPSHOT Documentation

Getting started