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<TITLE>Minimizing the Impact of Logging Code (Java Developers Almanac Example)
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    <B><A HREF="../java.util.logging/pkg.html">java.util.logging</A></B><font color="#666666" class="xsmall-font">
        &nbsp;[20 examples]
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  <h3>e389. Minimizing the Impact of Logging Code</h3>

It is good to add logging code to an application, but the logging code
should minimize its impact on the application, especially if the
logging is not enabled. In particular, if the message to be potentially
logged needs to be constructed, the method call should be wrapped in a
cheaper check.  For example, the method call


<pre>    int count = <font color="#0066ff"><i>123</i></font>;
    Logger logger = Logger.getLogger(<font color="#0066ff"><i>"com.mycompany.MyClass"</i></font>);
    logger.finest("count: "+count);
</pre>

will cause the count to be converted to a string and then concatenated
to another string. This is a lot of wasted work if the message will
not be logged.  To avoid this overhead, use <code>Logger.isLoggable()</code> to
check if the message would be logged before calling the logging
method.  For example,


<pre>    
    if (logger.isLoggable(Level.FINEST)) {
        logger.finest("count: "+count);
    }
</pre>
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            &nbsp;<b>Related Examples</b></font></td>
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e385. <a class="eglink" href="BasicLogging.html?l=rel">
    The Quintessential Logging Program
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e386. <a class="eglink" href="IsLog.html?l=rel">
    Determining If a Message Will Be Logged
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e387. <a class="eglink" href="LogMethod.html?l=rel">
    Logging a Method Call
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e388. <a class="eglink" href="LogExcept.html?l=rel">
    Logging an Exception
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e390. <a class="eglink" href="NoParent.html?l=rel">
    Preventing a Logger from Forwarding Log Records to Its Parent
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e391. <a class="eglink" href="LogFile.html?l=rel">
    Writing Log Records to a Log File
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e392. <a class="eglink" href="LogConsole.html?l=rel">
    Writing Log Records to Standard Error
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e393. <a class="eglink" href="LogMemory.html?l=rel">
    Writing Log Records Only After a Condition Occurs
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e394. <a class="eglink" href="SetFilter.html?l=rel">
    Setting a Filter on a Logger Handler
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        See also: 
<a class="eglink" href="/egs/java.util.logging/pkg.html?l=rel#Configuration">
    Configuration
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<a class="eglink" href="/egs/java.util.logging/pkg.html?l=rel#File%20Size">
    File Size
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<a class="eglink" href="/egs/java.util.logging/pkg.html?l=rel#Formatters">
    Formatters
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<a class="eglink" href="/egs/java.util.logging/pkg.html?l=rel#Levels">
    Levels
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