LanguageTool is a style and grammar checker that currently supports English, Polish, German, French, Dutch, and other languages to a different degree. It scans the words and their part-of-speech tags for occurrences of error patterns, which are defined in an XML file. More powerful error rules can be written in Java. LanguageTool should be used after the spelling of a text has been corrected.

Changes:
This release adds many updates for the error detection rules for English, French, German, Portuguese, Catalan, Polish, Russian, Breton, Esperanto, and Italian. LanguageTool is now modular, for easier use by Java developers. Instead of one big JAR, there are now several small ones (soon to be found at Maven Central). Several bugs have been fixed.

URL:
LanguageTool – Freecode

LanguageTool 2.1-0406_languagetool_2.1.png