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	<title>@Log</title>
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		<div class="header"><a href="../index.html">Project Lombok</a></div>
		<h1>@Log</h1>
		<div class="byline">Captain's Log, stardate 24435.7: &quot;What was that line again?&quot;</div>
		<div class="overview">
			<h3>Overview</h3>
			<p>
			<em>NEW in lombok 0.10: </em>You can annotate any field with <code>@Log</code> to let lombok generate a logger field automatically.<br />
			The logger is named <code>log</code> and field's type depends on which logger you have selected.
			</p><p>
			There are four <code>@Log</code> choices available:<br />
			<dl>
				<dt><code>@lombok.extern.apachecommons.Log</code></dt>
				<dd>Creates <code><span class="keyword">private&nbsp;static&nbsp;final&nbsp;</span><a href="http://commons.apache.org/logging/apidocs/org/apache/commons/logging/Log.html">org.apache.commons.logging.Log</a>&nbsp;<span class="staticfield">log</span>&nbsp;=&nbsp;<a href="http://commons.apache.org/logging/apidocs/org/apache/commons/logging/LogFactory.html#getLog(java.lang.Class)">org.apache.commons.logging.LogFactory.getLog</a>(LogExample.<span class="keyword">class</span>);</code></dd>
				<dt><code>@lombok.extern.jul.Log</code></dt>
				<dd>Creates <code><span class="keyword">private&nbsp;static&nbsp;final&nbsp;</span><a href="http://download.oracle.com/javase/6/docs/api/java/util/logging/Logger.html">java.util.logging.Logger</a>&nbsp;<span class="staticfield">log</span>&nbsp;=&nbsp;<a href="http://download.oracle.com/javase/6/docs/api/java/util/logging/Logger.html#getLogger(java.lang.String)">java.util.logging.Logger.getLogger</a>(LogExample.<span class="keyword">class</span>.getName());</code></dd>
				<dt><code>@lombok.extern.log4j.Log</code></dt>
				<dd>Creates <code><span class="keyword">private&nbsp;static&nbsp;final&nbsp;</span><a href="http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Logger.html">org.apache.log4j.Logger</a>&nbsp;<span class="staticfield">log</span>&nbsp;=&nbsp;<a href="http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Logger.html#getLogger(java.lang.Class)">org.apache.log4j.Logger.getLogger</a>(LogExample.<span class="keyword">class</span>);</code></dd>
				<dt><code>@lombok.extern.slf4j.Log</code></dt>
				<dd>Creates <code><span class="keyword">private&nbsp;static&nbsp;final&nbsp;</span><a href="http://www.slf4j.org/api/org/slf4j/Logger.html">org.slf4j.Logger</a>&nbsp;<span class="staticfield">log</span>&nbsp;=&nbsp;<a href="http://www.slf4j.org/apidocs/org/slf4j/LoggerFactory.html#getLogger(java.lang.Class)">org.slf4j.LoggerFactory.getLogger</a>(LogExample.<span class="keyword">class</span>);</code></dd>
			</dl>
			</p>
			<p>
			All <code>@Log</code> annotations can take an optional parameter of type <code>Class</code>. If such a parameter is specified, that class will be used as the parameter for the logger factory call.
			</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>
				If a field called <code>log</code> already exists, a warning will be emitted and no code will be generated.
				</p><p>
				A future feature of lombok's <code>@Log</code> is to find calls to the logger field and, if the chosen logging framework supports
				it and the log level can be compile-time determined from the log call, guard it with an <code>if</code> statement. This way if
				the log statement ends up being ignored, the potentially expensive calculation of the log string is avoided entirely. This does mean
				that you should <em>NOT</em> put any side-effects in the expression that you log.
				</p>
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