Thymeleaf Property Extractor (ThExtractor in short) is a java-written app that given a folder or a html file, extracts every Thymeleaf localisation tags (for example: th:text="#{myString}") to a properties file, to ease and fasten the development of your Spring web app.
It's really easy to use! Just run the jar, and browse for your HTML (or a folder containing them) in the first field, and browse for a target .properties file (or create one!) in the second field. And then... do magic!