47 lines
1.7 KiB
HTML
47 lines
1.7 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
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<html>
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<head>
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<title>Checks for imports</title>
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<link rel="stylesheet" type="text/css" href="mystyle.css">
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</head>
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<body>
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<h1>Checks for imports</h1>
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<p>The property <span class="code">checkstyle.ignore.imports</span> controls
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whether to check import statements. The property type is <a
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href="property_types.html#boolean">boolean</a> and defaults to <span
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class="default">false</span>.</p>
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<p>Checkstyle uses a simple but very reliable algorithm to report on unused import statements. An import statement is considered unused if:</p>
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<ul>
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<li>It is not referenced in the file. The algorithm does not support
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wild-card imports like <span class="code">import java.io.*;</span>. Most
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IDE's provide very sophisticated checks for imports that handle wild-card
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imports.</li>
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<li>It is a duplicate of another import. This is when a class is imported
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more than once.</li>
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<li>The class imported is from the <span class="code">java.lang</span>
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package. For example importing <span
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class="code">java.lang.String</span>.</li>
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<li>The class imported is from the same package.</li>
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</ul>
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<p>The property <span class="code">checkstyle.illegal.imports</span> contains
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the set of import illegal package prefixes for import statements. The property
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type is <a href="property_types.html#stringSet">string set</a> and defaults to
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<span class="code">sun</span> since programs that contain direct calls to the
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<span class="code">sun.*</span> packages are <a
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href="http://java.sun.com/products/jdk/faq/faq-sun-packages.html">not 100%
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Pure Java</a>.</p>
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<hr>
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<p align="center">Copyright © 2002 Oliver Burn. All rights Reserved.</p>
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</body>
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</html> |