Doxygen is a technical documentation generator for C++, C, Java and others languages.
When this option is configured, Hudson can provide a link for the Doxygen documentation.
You can choose between

• "Use the Doxyfile information" for a Doxyfile parsing
• "Use the Doxygen HTML directory" in the case the Doxyfile is not used or has a lack of information, e.g. when the Doxygen execution use the command line or when a property is overriden in some way