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<document>
  <properties>
    <title>Developer guide for Commons "Text"</title>
  </properties>
  <body>

    
    <section name='Developer guide for Commons "Text"'>

      <h1>The Commons <em>Text</em> Package</h1>
      <h2>Developers Guide</h2>
      <br />
      <a href="#Introduction">[Introduction]</a>
      <a href="#PackageStructure">[Package Structure]</a>
      <a href="#UtilityClasses">[Utility Classes]</a>
      <a href="#Javadoc">[Javadoc]</a>
      <a href="#Building">[Building]</a>
      <br /><br />

      <a name="Introduction"></a>
      <h3>1.  INTRODUCTION</h3>

      <p>The <em>Text</em> package contains a set of Java classes that contain algorithms for measuring
        and manipulating string. This developer guide seeks to set
        out rules for the naming of classes and methods within the package. The purpose
        of this, as with all naming standards, is to improve the coherency and
        consistency of the whole API.</p>

      <p>The philosophy of the naming standards is to follow those of the JDK
        if possible.</p>



      <a name="PackageStructure"></a>
      <h3>2.  PACKAGE STRUCTURE</h3>

      <p>The main package for Text is <code>org.apache.commons.text</code>. Subpackages should
        be created for each group of related items. </p>

      <p>Each package should have a <code>package.html</code> file for javadoc. This should
        describe the use of the package and its scope.</p>



      <a name="UtilityClasses"></a>
      <h3>3.  UTILITY CLASSES</h3>

      <p>Utility classes provide additional functionality around a class or interface.
        Examples include StringUtils and StringEscapeUtils.</p>

      <p>Each class shall follow the naming pattern XxxUtils where Xxx relates to the
        class or interface that the utility services. Variations on a theme (<code>Integer</code>
        as opposed to <code>Number</code>) should be dealt with in one Utils class where possible.
        Each Utils class shall:</p>

      <ul>
        <li>be a single, static method based, class</li>
        <li>have a name consisting of the interface name plus 'Utils'</li>
        <li>deal with one class or interface and its variations (subclasses)</li>
        <li>provide methods that perform useful utility functions</li>
        <li>the class will not be final</li>
        <li>for null parameters, rather than throwing an Exception, consider performing a Null patterned concept, such as returning 0 or ""</li>
      </ul>

      <p>A utility class can act as a factory for specific implementations of a class or
        interface. In such cases the implementations should be non-public, static, inner classes
        of the utility class. However, if warranted due to maintenance or other reasons, these
        decorator classes may be moved to top-level classes in a subpackage.  The
        naming of such a subpackage should be discussed and agreed upon on the
        developers mailing list.</p>

      <p>If different overloaded variants of a method are desired, with the same method signature, it should not be indicated via a boolean argument, but via a more focused method name. Rather than replace(boolean repeat), replace and replaceAll, or replaceOnce and replace. </p>


      <a name="Javadoc"></a>
      <h3>4.  JAVADOC</h3>

      <p>The Sun javadoc guidelines are the starting point for Text. These points are
        an extension to make it easier for users reading the generated
        docs and developers with javadoc-popup capabilities from within their IDE.</p>

      <h4>General</h4>
      <p>References to other objects, interfaces or methods use the @link-tag the
        first time it is referenced in a class or interface. On the following
        references always enclose it inside &lt;code&gt;&lt;/code&gt;.</p>

      <p>References to <code>null</code>, <code>this</code>, <code>long</code>,
        <code>int</code>, <code>short</code>, <code>char</code>, <code>byte</code>,
        <code>double</code>, <code>float</code> and <code>boolean</code> should be enclosed
        in &lt;code&gt;&lt;/code&gt;.</p>

      <h4>Classes/Interfaces/Methods</h4>
      <p>Use a short description of what the class/interface/method is used for,
        enclose with &lt;p&gt;&lt;/p&gt;.</p>

      <p>A longer description about what the class/interface/method is used for
        and if it is needed how it is done. If it is necessary include
        description of the parameters, what they are used for and how. Enclose
        with &lt;p&gt;&lt;/p&gt; where it is needed, try to divide into smaller parts (not
        to small!) to enhance readability of the generated Javadoc.</p>

      <p>If an example is needed enclose it with &lt;pre&gt;&lt;/pre&gt;.
        It should be supported with an explanation within a normal paragraph.</p>

      <h4>Exception throwing</h4>
      <p>When throwing an exception to indicate a bad argument, always try to throw
        IllegalArgumentException, even if the argument was null. Do not throw
        NullPointerException. (Obviously, you should document what the code actually does!)</p>

      <h4>Deprecations</h4>
      <p>When deprecating a method or class include a clear reference to when the method will be deleted.
        This should be of the form 'Method will be removed in Commons Text 2.0.'. </p>

      <h4>Language used in code/comments</h4>
      <p>It has been decided to casually standardize on US-English.
        To avoid misplaced jeers of 'americanisation', the people making this decision largely write in non-US-English.
        However, it's not something to get worked up about.  Lots of spelling differences will creep in all over.</p>

      <a name="Building"></a>
      <h3>5.BUILDING</h3>
      <h4>Building a Release</h4>
      <p>
        The currently targeted version of Java is 8.
      </p>
      <p>
        To build Text:
        <table>
          <tr><th></th><th>Tested JAR</th><th>Distribution</th><th>Site</th></tr>
          <tr><td>Maven 3.x</td><td><code>mvn package</code></td><td><code>mvn assembly:assembly</code></td><td><code>mvn site</code></td></tr>
        </table>
      </p>
    </section>
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</document>