How to prompt language code within a plugin?

Hi,

I am using ckeditor in a multilanguage website (english, geman, french, etc.). Now I have a plugin that outputs some text. Of course the output should be in the same language, which is active in ckeditor.

So how do I prompt/retrieve the language code so that a can give the output in the right language?

Should be something like this:
if (language_code=='de') output='Guten Tag';
if (language_code=='en') output='Hi';
if (language_cod}=='fr') output='Bonjour';

Any Ideas?