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<title>@Getter(lazy=true)</title>
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<h1>@Getter(lazy=true)</h1>
<div class="byline">Laziness is a virtue!</div>
<div class="overview">
<h3>Overview</h3>
<p>
<em>NEW IN Lombok 0.10: </em>You can let lombok generate a getter which will calculate a value once, the first time this getter is called, and cache it from then on. This can be useful
if calculating the value takes a lot of CPU, or the value takes a lot of memory. To use this feature, create a <code>private final</code> variable,
initialize it with the expression that's expensive to run, and annotate your field with <code>@Getter(lazy=true)</code>. The field will be hidden from the
rest of your code, and the expression will be evaluated no more than once, when the getter is first called. There are no magic marker values (i.e. even
if the result of your expensive calculation is <code>null</code>, the result is cached) and your expensive calculation need not be thread-safe, as lombok
takes care of locking.
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<h3>With Lombok</h3>
<div class="snippet">@HTML_PRE@</div>
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<h3>Vanilla Java</h3>
<div class="snippet">@HTML_POST@</div>
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<h3>Small print</h3><div class="smallprint">
<p>
Lombok actually creates a few fields all prefixed with <code>$lombok$</code> to cache the value. You should not rely on the exact type, name, and structure
of these fields as future implementations may change them. To access the lazily initialized value, <em>always</em> use the generated getter.
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Other Lombok annotations such as <code>@ToString</code> always call the getter even if you use <code>doNotUseGetters=true</code>.
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