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diff --git a/website-old/features/Cleanup.html b/website-old/features/Cleanup.html new file mode 100644 index 00000000..37e53c18 --- /dev/null +++ b/website-old/features/Cleanup.html @@ -0,0 +1,86 @@ +<!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>@Cleanup</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>@Cleanup</h1> + <div class="byline">Automatic resource management: Call your <code>close()</code> methods safely with no hassle.</div> + <div class="overview"> + <h3>Overview</h3> + <p> + You can use <code>@Cleanup</code> to ensure a given resource is automatically cleaned up before the code execution path exits your + current scope. You do this by annotating any local variable declaration with the <code>@Cleanup</code> annotation like so:<br /> + <code>@Cleanup InputStream in = new FileInputStream("some/file");</code><br /> + As a result, at the end of the scope you're in, <code>in.close()</code> is called. This call is guaranteed to run by way of a + try/finally construct. Look at the example below to see how this works. + </p><p> + If the type of object you'd like to cleanup does not have a <code>close()</code> method, but some other no-argument method, you can + specify the name of this method like so:<br /> + <code>@Cleanup("dispose") org.eclipse.swt.widgets.CoolBar bar = new CoolBar(parent, 0);</code><br /> + By default, the cleanup method is presumed to be <code>close()</code>. A cleanup method that takes 1 or more arguments cannot be called via + <code>@Cleanup</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.cleanup.flagUsage</code> = [<code>warning</code> | <code>error</code>] (default: not set)</dt> + <dd>Lombok will flag any usage of <code>@Cleanup</code> as a warning or error if configured.</dd> + </dl> + </div> + <div class="overview"> + <h3>Small print</h3><div class="smallprint"> + <p> + In the finally block, the cleanup method is only called if the given resource is not <code>null</code>. However, if you use <code>delombok</code> + on the code, a call to <code>lombok.Lombok.preventNullAnalysis(Object o)</code> is inserted to prevent warnings if static code analysis could + determine that a null-check would not be needed. Compilation with <code>lombok.jar</code> on the classpath removes that method call, + so there is no runtime dependency. + </p> + <p> + If your code throws an exception, and the cleanup method call that is then triggered also throws an exception, then the original exception + is hidden by the exception thrown by the cleanup call. You should <em>not</em> rely on this 'feature'. Preferably, lombok would like to generate + code so that, if the main body has thrown an exception, any exception thrown by the close call is silently swallowed (but if the main body + exited in any other way, exceptions by the close call will not be swallowed). The authors of lombok do not currently know of a feasible way + to implement this scheme, but if java updates allow it, or we find a way, we'll fix it. + </p><p> + You do still need to handle any exception that the cleanup method can generate! + </p> + </div> + </div> + <div class="footer"> + <a href="index.html">Back to features</a> | <a href="NonNull.html">Previous feature (@NonNull)</a> | <a href="GetterSetter.html">Next feature (@Getter / @Setter)</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) ? "https://ssl." : "http://www."); + document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); +</script> +<script type="text/javascript"> + try { + var pageTracker = _gat._getTracker("UA-9884254-1"); + pageTracker._trackPageview(); + } catch(err) {} +</script> +</body></html> |