XHTML processing
After the XHTML files are generated by the common routine, the dita.map.xhtml target is
    called by the xhtml transformation. This target generates a TOC file called
      index.html, which can be loaded into a frameset.
After the XHTML files are generated by the common routine, the dita.map.xhtml target is
    called by the xhtml transformation. This target generates a TOC file called
      index.html, which can be loaded into a frameset.