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<TITLE>Logging a Message in a Servlet
(Java Developers Almanac Example)
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<META CONTENT="Patrick Chan" NAME="AUTHOR">
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<B><A HREF="../javax.servlet/pkg.html">javax.servlet</A></B><font color="#666666" SIZE="-2">
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<h3>
e1038.
Logging a Message in a Servlet</h3>
The servlet container provides a simple logging facility for a servlet
to log text messages and exceptions. For a more full-featured logging
facility, see the <code>java.util.logging</code> package.
<pre>
// See also <a href="../javax.servlet/com_mycompany_MyServlet.html" class="eglink"><font size="-1"><b>e1034</b> The Quintessential Servlet</font></a>
// Add an entry to the log file
getServletContext().log(<font color="#0066ff"><i>"A message"</i></font>);
try {
// ...
} catch (Exception e) {
// Add an entry to the log file and include an exception
getServletContext().log(<font color="#0066ff"><i>"An exception occurred"</i></font>, e);
}
</pre>
Here's a sample of the log entries in Tomcat:
<pre>
2002-07-06 21:12:54 A message
2002-07-06 21:12:54 An exception occurred
java.io.IOException
at com.mycompany.MyServlet.doGet(Unknown Source)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
...
</pre>
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Related Examples
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e1034. <a class="eglink" href="com_mycompany_MyServlet.html?l=rel">
The Quintessential Servlet
</a>
<br>
e1035. <a class="eglink" href="GetInit.html?l=rel">
Getting and Setting Initialization Parameters for a Servlet
</a>
<br>
e1036. <a class="eglink" href="GetImage.html?l=rel">
Returning an Image in a Servlet
</a>
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e1037. <a class="eglink" href="State.html?l=rel">
Saving Data in a Servlet
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