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diff --git a/website/features/NonNull.html b/website/features/NonNull.html new file mode 100644 index 00000000..9faad502 --- /dev/null +++ b/website/features/NonNull.html @@ -0,0 +1,73 @@ +<!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>val</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>@NonNull</h1> + <div class="byline">or: How I learned to stop worrying and love the NullPointerException.</div> + <div class="overview"> + <h3>Overview</h3> + <p> + <em>NEW in Lombok 0.11.10: </em>You can use <code>@NonNull</code> on the parameter of a method or constructor to have lombok generate a null-check statement for you. + </p><p> + Lombok has always treated any annotation named <code>@NonNull</code> on a field as a signal to generate a null-check if lombok generates an entire method or constructor for you, via + for example <a href="Data.html"><code>@Data</code></a>. Now, however, using lombok's own <code>@lombok.NonNull</code> on a parameter results in the insertion of just the null-check + statement inside your own method or constructor. + </p><p> + The null-check looks like <code>if (param == null) throw new NullPointerException("param");</code> and will be inserted at the very top of your method. For constructors, the null-check + will be inserted immediately following any explicit <code>this()</code> or <code>super()</code> calls. + </p><p> + If a null-check is already present at the top, no additional null-check will be generated. + </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"> + <h3>Small print</h3><div class="smallprint"> + <p> + Lombok's detection scheme for already existing null-checks consists of scanning for if statements that look just like lombok's own. Any 'throws' statement as + the 'then' part of the if statement, whether in braces or not, counts. The conditional of the if statement <em>must</em> look exactly like <code>PARAMNAME == null</code>. + The first statement in your method that is not such a null-check stops the process of inspecting for null-checks. + </p><p> + While <code>@Data</code> and other method-generating lombok annotations will trigger on any annotation named <code>@NonNull</code> regardless of casing or package name, + this feature only triggers on lombok's own <code>@NonNull</code> annotation from the <code>lombok</code> package. + </p><p> + A <code>@NonNull</code> on a primitive parameter results in a warning. No null-check will be generated. + </p> + </div> + </div> + <div class="footer"> + <a href="index.html">Back to features</a> | <a href="val.html">Previous feature (val)</a> | <a href="Cleanup.html">Next feature (@Cleanup)</a><br /> + <a href="../credits.html" class="creditsLink">credits</a> | <span class="copyright">Copyright © 2013 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> |