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<overview>

<p>

This metric measures the number of different authors (by examining the

version control history)

for files below this location in the tree. (This is a better version

of the metric that counts the number of different authors using Javadoc

tags.)

</p>

<p>

Files that have been changed by a large number of different authors are

by definition the product of many minds. New authors working on a file

may be less familiar with the design and implementation of the code than

the original authors, which can be a potential source of bugs. Furthermore,

code that has been worked on by many people, if not carefully maintained,

often ends up lacking conceptual integrity. For both of these reasons, any

code that has been worked on by an unusually high number of different people

merits careful inspection in code reviews.

</p>

</overview>

<recommendation>

<p>

There is clearly no way to reduce the number of authors that have worked

on a file - it is impossible to rewrite history. However, files highlighted

by this metric should be given special attention in a code review, and may

ultimately be good candidates for refactoring/rewriting by an individual,

experienced developer.

</p>

</recommendation>

<references>

<li>

F. P. Brooks Jr. <em>The Mythical Man-Month</em>, Chapter 4. Addison-Wesley, 1974.

</li>

</references>

</qhelp>