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<qhelp>

<overview>

<p>

This metric measures the number of lines of code for each type.

</p>

<p>

Large types can be problematic:

</p>

<ul>

<li>

They can be hard to understand and maintain, even with good tool support.

</li>

<li>

They often arise as a result of bundling many unrelated things into the same

type, and so can be a symptom of weak type cohesion.

</li>

</ul>

</overview>

<recommendation>

<p>

Types are generally too large because they are taking on more responsibilities

than they should (see [Martin] for more on responsibilities). In general, the

solution is to identify each of the different responsibilities the class is

taking on, and split them out into multiple classes, e.g. using the 'Extract

Class' refactoring from [Fowler].

</p>

</recommendation>

<references>

<li>

M. Fowler. <em>Refactoring</em> pp. 65, 122-5. Addison-Wesley, 1999.

</li>

<li>

R. Martin. <em>Agile Software Development: Principles, Patterns, and Practices</em>

Chapter 8 - SRP: The Single-Responsibility Principle. Pearson Education, 2003.

</li>

</references>

</qhelp>