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Internationalization (i18n for short) in Kettle is handled by a graphical user interface called Translator, org.pentaho.di.ui.i18n.editor.Translator2 to be precise. A script is provided for Windows (Translator.bat) and Linux/OSX/Unix systems (translator.sh).
This application will allow a translator to edit the translations for the keys that are used in the Kettle source code.
To run Translator you will need access to the source code and have a Java 1.5 development kit installed. You also need ant to compile Kettle. Once you ran ant and built the Kettle libraries, you can execute translator from the root of the Kettle source code folder.
Translator
The translator GUI allows you access to all the available locale that are available. It will colour those packages that contain messages files that are lacking translations compared to en_US. You can then simply enter the translations and update the corresponding messages files. For example, updating the fr_FR (French - France) translations in package org.pentaho.di.core.plugins would lead to an update in file src-core/org/pentaho/di/core/plugins/messages/messages_fr_FR.properties. The Translator application takes care of proper UTF-8 encoding of the properties files as well as figuring out the proper place to store the file.
By only offering to translate used i18n keys, a lot of time is saved since on long-lived active projects like Kettle there is usually a lot of code being changed with a lot of "dead" or unused keys as a result. Not having to translate these keys leads to a lot of effort saved since each key is picked up by (currently) 11 locale.
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How does it work?
Translator can detect keys that are not yet translated. It does this by scanning both the Java and XUL source code as well as the messages bundles. It then correlates both and determines missing keys.
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