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<!DOCTYPE html>
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	<title>@Data</title>
</head><body><div id="pepper">
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	<div class="meat">
		<div class="header"><a href="../index.html">Project Lombok</a></div>
		<h1>@Data</h1>
		<div class="byline">All together now: A shortcut for <code>@ToString</code>, <code>@EqualsAndHashCode</code>,
			<code>@Getter</code> on all fields, and <code>@Setter</code> on all non-final fields. You even
			get a free constructor to initialize your final fields!</div>
		<div class="overview">
			<h3>Overview</h3>
			<p>
			<code>@Data</code> is a convenient shortcut annotation that bundles the features of <a href="ToString.html"><code>@ToString</code></a>,
			<a href="EqualsAndHashCode.html">@EqualsAndHashCode</code></a> and <a href="GetterSetter.html"><code>@Getter</code> / <code>@Setter</code></a>
			together: In other words, <code>@Data</code> generates <em>all</em> the boilerplate that is normally associated with simple POJOs
			(Plain Old Java Objects) and beans: getters for all fields, setters for all non-final fields, and appropriate <code>toString</code>, <code>equals</code>
			and <code>hashCode</code> implementations that involve the fields of the class. In addition, <code>@Data</code> generates a constructor that
			initialized all final fields.
			</p><p>
			<code>@Data</code> is like having implicit <code>@ToString</code> and <code>@EqualsAndHashCode</code> annotations on the class.
			However, the parameters of <code>@ToString</code> and <code>@EqualsAndHashCode</code> (such as <code>callSuper</code>, <code>includeFieldNames</code> and
			<code>exclude</code>) cannot be set with <code>@Data</code>. If you need to set non-default values for any of these parameters, just add those annotations
			explicitly; <code>@Data</code> is smart enough to defer to those annotations.
			</p><p>
			All generated getters and setters will be <code>public</code>. To override the access level, annotate the field with an explicit <code>@Setter</code> and/or
			<code>@Getter</code> annotation.
			</p><p>
			All fields marked as <code>transient</code> will not be considered for <code>hashCode</code> and <code>equals</code>. All static fields will be
			skipped entirely (not considered for any of the generated methods, and no setter/getter will be made for them).
			</p><p>
			If the class already contains a method with the same name as any method that would normally be generated, that method is not generated, and no warning or
			error is emitted. For example, if you already have a method with signature <code>void hashCode(int a, int b, int c)</code>, no <code>int hashCode()</code>
			method will be generated, even though technically <code>int hashCode()</code> is an entirely different method. The same rule applies to the constructor,
			<code>toString</code>, <code>equals</code>, and all getters and setters.
			</p><p>
			<code>@Data</code> can handle generics parameters for fields just fine. In order to reduce the boilerplate when constructing objects for classes with
			generics, you can use the <code>staticConstructor</code> parameter to generate a private constructor, as well as a static method that returns a new
			instance. This way, javac will infer the variable name. Thus, by declaring like so: <code>@Data(staticConstructor="of") class Foo&lt;T&gt; { private T x;}</code>
			you can create new instances of <code>Foo</code> by writing: <code>Foo.of(5);</code> instead of having to write: <code>new Foo&lt;Integer&gt;(5);</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">
			<h3>Small print</h3><div class="smallprint">
				<p>See the small print of <a href="ToString.html"><code>@ToString</code></a>, <a href="EqualsAndHashCode.html"><code>@EqualsAndHashCode</code></a> and
					<a href="GetterSetter.html"><code>@Getter / @Setter</code></a>.
			</div>
		</div>
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			<a href="index.html">Back to features</a> | <a href="EqualsAndHashCode.html">Previous feature (@EqualsAndHashCode)</a> | <a href="Cleanup.html">Next feature (@Cleanup)</a><br />
			<a href="../credits.html" class="creditsLink">credits</a> | <span class="copyright">Copyright &copy; 2009 Reinier Zwitserloot and Roel Spilker, licensed under the <a href="http://www.opensource.org/licenses/mit-license.php">MIT licence</a>.</span>
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