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diff --git a/website-old/features/experimental/ExtensionMethod.html b/website-old/features/experimental/ExtensionMethod.html deleted file mode 100644 index 7090fd19..00000000 --- a/website-old/features/experimental/ExtensionMethod.html +++ /dev/null @@ -1,116 +0,0 @@ -<!DOCTYPE html> -<html><head> - <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> - <link rel="stylesheet" type="text/css" href="../../logi/reset.css" /> - <link rel="stylesheet" type="text/css" href="../features.css" /> - <link rel="shortcut icon" href="../../favicon.ico" type="image/x-icon" /> - <meta name="description" content="Spice up your java" /> - <title>EXPERIMENTAL – @ExtensionMethod</title> -</head><body><div id="pepper"> - <div class="minimumHeight"></div> - <div class="meat"> - <div class="header"><a href="../../index.html">Project Lombok</a></div> - <h1>@ExtensionMethod</h1> - <div class="byline">Annoying API? Fix it yourself: Add new methods to existing types!</div> - <div class="since"> - <h3>Since</h3> - <p> - @ExtensionMethod was introduced as experimental feature in lombok v0.11.2. - </p> - </div> - <div class="experimental"> - <h3>Experimental</h3> - <p> - Experimental because: - <ul> - <li>High-impact on code style</li> - <li>Really would like to ship with utility methods to expand common classes, but so far lombok doesn't have a good distribution method for such runtime dependencies</li> - <li>Affects quite a bit of eclipse, and auto-complete e.d. do not work yet in netbeans</li> - <li>Should @ExtensionMethod be legal on methods? Should it be legal on packages?</li> - </ul> - Current status: <em>positive</em> - Currently we feel this feature may move out of experimental status with no or minor changes soon. - </div> - <div class="overview"> - <h3>Overview</h3> - <p> - You can make a class containing a bunch of <code>public</code>, <code>static</code> methods which all take at least 1 - parameter. These methods will extend the type of the first parameter, as if they were instance methods, using the - <code>@ExtensionMethod</code> feature. - </p> - </p><p> - For example, if you create <code>public static String toTitleCase(String in) { ... }</code>, you can use the - <code>@ExtensionMethod</code> feature to make it look like the <code>java.lang.String</code> class has a method named - <code>toTitleCase</code>, which has no arguments. The first argument of the static method fills the role of <code>this</code> - in instance methods. - </p><p> - All methods that are <code>public</code>, <code>static</code>, and have at least 1 argument whose type is not primitive, are - considered extension methods, and each will be injected into the namespace of the type of the first parameter as if they were - instance methods. As in the above example, a call that looks like: <code>foo.toTitleCase()</code> is replaced with - <code>ClassContainingYourExtensionMethod.toTitleCase(foo);</code>. Note that it is actually not an instant - <code>NullPointerException</code> if <code>foo</code> is null - it is passed like any other parameter. - </p><p> - You can pass any number of classes to the <code>@ExtensionMethod</code> annotation; they will all be searched for - extension methods. These extension methods apply for any code that is in the annotated class. - </p><p> - Lombok does not (currently) have any runtime dependencies which means lombok does not (currently) ship with any useful - extension methods so you'll have to make your own. However, here's one that might spark your imagination: - <pre>public class ObjectExtensions { - public static <T> or(T object, T ifNull) { - return object != null ? object : ifNull; - } -}</pre> - With the above class, if you add <code>@ExtensionMethod(ObjectExtensions.class)</code> to your class definition, you can write: - <pre>String x = null; -System.out.println(x.or("Hello, World!"));</pre> - The above code will not fail with a <code>NullPointerException</code>; it will actually output <code>Hello, World!</code> - </p> - </div> - <div class="snippets"> - <div class="pre"> - <h3>With Lombok</h3> - <div class="snippet">@HTML_PRE@</div> - </div> - <div class="sep"></div> - <div class="post"> - <h3>Vanilla Java</h3> - <div class="snippet">@HTML_POST@</div> - </div> - </div> - <div style="clear: left;"></div> - <div class="overview confKeys"> - <h3>Supported configuration keys:</h3> - <dl> - <dt><code>lombok.extensionMethod.flagUsage</code> = [<code>warning</code> | <code>error</code>] (default: not set)</dt> - <dd>Lombok will flag any usage of <code>@ExtensionMethod</code> as a warning or error if configured.</dd> - </dl> - </div> - <div class="overview"> - <h3>Small print</h3><div class="smallprint"> - <p> - Calls are rewritten to a call to the extension method; the static method itself is not inlined. Therefore, the - extension method must be present both at compile and at runtime. - </p><p> - Generics is fully applied to figure out extension methods. i.e. if the first parameter of your extension method is - <code>List<? extends String></code>, then any expression that is compatible with that will have your extension method, - but other kinds of lists won't. So, a <code>List<Object></code> won't get it, but a <code>List<String></code> will. - </p> - </div> - </div> - <div class="footer"> - <a href="index.html">Back to experimental features</a> | <a href="Accessors.html">Previous feature (@Accessors)</a> | <a href="FieldDefaults.html">Next feature (@FieldDefaults)</a><br /> - <a href="../../credits.html" class="creditsLink">credits</a> | <span class="copyright">Copyright © 2009-2016 The Project Lombok Authors, licensed under the <a href="http://www.opensource.org/licenses/mit-license.php">MIT license</a>.</span> - </div> - <div style="clear: both;"></div> - </div> -</div> -<script type="text/javascript"> - var gaJsHost = (("https:" == document.location.protocol) ? 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