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<TITLE>Logging an Exception
(Java Developers Almanac Example)
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<META CONTENT="Patrick Chan" NAME="AUTHOR">
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<B><A HREF="../java.util.logging/pkg.html">java.util.logging</A></B><font color="#666666" SIZE="-2">
[20 examples]
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<h3>
e388.
Logging an Exception</h3>
The logger method <code>log()</code> can be used to log an exception. Also, the
convenience method <code>Logger.throwing()</code> can be used by a method about to
throw an exception.
<pre>
package <font color="#0066ff"><i>com.mycompany</i></font>;
class <font color="#0066ff"><i>MyClass</i></font> {
public void <font color="#0066ff"><i>myMethod</i></font>() {
Logger logger = Logger.getLogger(<font color="#0066ff"><i>"com.mycompany.MyClass"</i></font>);
// This method should be used when an exception is encounted
try {
// Test with an exception
throw new IOException();
} catch (Throwable e){
// Log the exception
logger.log(Level.SEVERE, "Uncaught exception", e);
}
// When a method is throwing an exception, this method should be used
Exception ex = new IllegalStateException();
logger.throwing(this.getClass().getName(), <font color="#0066ff"><i>"myMethod"</i></font>, ex);
}
}
</pre>
Here is a sample of the output generated by the example:
<pre>
Jan 11, 2002 5:16:49 PM com.mycompany.MyClass myMethod
SEVERE: Uncaught exception
java.io.IOException
at com.mycompany.MyClass.myMethod(com.mycompany.MyClass.java:32)
at com.mycompany.MyClass.main(com.mycompany.MyClass.java:18)
Jan 11, 2002 5:16:50 PM com.mycompany.MyClass myMethod
FINER: THROW
java.lang.IllegalStateException
at com.mycompany.MyClass.myMethod(com.mycompany.MyClass.java:25)
at com.mycompany.MyClass.main(com.mycompany.MyClass.java:18)
</pre>
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Related Examples
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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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e389. <a class="eglink" href="Minimize.html?l=rel">
Minimizing the Impact of Logging Code
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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
</a>
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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
</a>
<a class="eglink" href="/egs/java.util.logging/pkg.html?l=rel#Formatters">
Formatters
</a>
<a class="eglink" href="/egs/java.util.logging/pkg.html?l=rel#Levels">
Levels
</a>
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