Message Facility provides a JSR 269 Annotation Processor for the @Msg annotation, and will produce XML resources to serve as runtime message patterns.

The XML resource generated for the Simple class is __generated_src/tutor/msg/Simple.msg.xml with the following content:

<?xml version="1.0" encoding="UTF-8"?>
<java>
  <text>
    <yr-age>
      <![CDATA[{name} was {age} {! age>1 ? "years" : "year"} old in year {year}.]]>
      <args>
        <name>name of the person</name>
        <age default-value="26">his/her age in that year</age>
        <year default-value="2002">the year</year>
      </args>
      <usage>
        This is a demo message declaiming one person's age in a past year.
      </usage>
      <defined>tutor.msg.Simple(Simple.java:24)</defined>
      <used>tutor.msg.Simple(Simple.java:24)</used>
    </yr-age>
  </text>
</java>

This snippet is indent adjusted result from __generated_src/tutor/msg/Simple.msg.xml