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<h2 class="title" style="clear: both"><a id="dbErrorReporting"></a>Error Reporting Functions</h2>
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<p>
To simplify error reporting and handling, the
<span><tt class="classname">DatabaseConfig</tt> class</span>
offers several useful methods.
</p>
<div class="itemizedlist">
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<li>
<p>
<tt class="methodname">DatabaseConfig.setErrorStream()</tt>
</p>
<p>
Sets the
<span>Java <tt class="classname">OutputStream</tt></span>
to be used for displaying error messages issued by the DB library.
</p>
</li>
<li>
<p>
<tt class="methodname">DatabaseConfig.setMessageHandler()</tt>
</p>
<p>
Defines the message handler that is called when an error message is
issued by DB. The error prefix and message are passed to
this callback. It is up to the application to display this
information correctly.
</p>
<p>
Note that the message handler must be an implementation of the
<tt class="classname">com.sleepycat.db.MessageHandler</tt>
interface.
</p>
</li>
<li>
<p>
<tt class="methodname">DatabaseConfig.setErrorPrefix()</tt>
</p>
<p>
Sets the prefix used for any error messages issued by the
DB library.
</p>
</li>
</ul>
</div>
<p>
For example, to send all your error messages to a particular message
handler, first implement the handler:
</p>
<a id="java_db10"></a>
<pre class="programlisting">package db.GettingStarted;
import com.sleepycat.db.Environment;
import com.sleepycat.db.MessageHandler;
public class MyMessageHandler implements MessageHandler {
// Our constructor does nothing
public MyMessageHandler() {}
public void message(Environment dbenv, String message)
{
// Put your special message handling code here
}
}</pre>
<p>
And then set up your database to use the message handler by identifying
it on the database's <tt class="classname">DatabaseConfig</tt> object:
</p>
<a id="java_db11"></a>
<pre class="programlisting">package db.GettingStarted;
import com.sleepycat.db.DatabaseConfig;
...
DatabaseConfig myDbConfig = new DatabaseConfig();
MyMessageHandler mmh = new MyMessageHandler();
myDbConfig.setMessageHandler(mmh); </pre>
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