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32            <h2 class="title" style="clear: both"><a id="dbErrorReporting"></a>Error Reporting Functions</h2>
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36      <p>
37        To simplify error reporting and handling, the
38        
39        
40        <span><code class="classname">DatabaseConfig</code> class</span>
41        offers several useful methods. 
42        
43        
44        
45
46    </p>
47      <div class="itemizedlist">
48        <ul type="disc">
49          <li>
50            <p>
51                
52                <code class="methodname">DatabaseConfig.setErrorStream()</code>
53            </p>
54            <p>
55                Sets the 
56                    
57                    <span>Java <code class="classname">OutputStream</code></span>
58                to be used for displaying error messages issued by the DB library. 
59            </p>
60          </li>
61          <li>
62            <p>
63                
64                <code class="methodname">DatabaseConfig.setMessageHandler()</code>
65            </p>
66            <p>
67                Defines the message handler that is called when an error message is
68                issued by DB. The error prefix and message are passed to
69                this callback. It is up to the application to display this
70                information correctly.
71            </p>
72            <p>
73                Note that the message handler must be an implementation of the
74                <code class="classname">com.sleepycat.db.MessageHandler</code>
75                interface.
76            </p>
77          </li>
78          <li>
79            <p>
80                
81                <code class="methodname">DatabaseConfig.setErrorPrefix()</code>
82            </p>
83            <p>
84                Sets the prefix used for any error messages issued by the
85                DB library.
86            </p>
87          </li>
88        </ul>
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90      <p>
91        For example, to send all your error messages to a particular message
92        handler, first implement the handler:
93    </p>
94      <a id="java_db10"></a>
95      <pre class="programlisting">package db.GettingStarted;
96
97import com.sleepycat.db.Environment;
98import com.sleepycat.db.MessageHandler;
99
100public class MyMessageHandler implements MessageHandler  {
101
102    // Our constructor does nothing
103    public MyMessageHandler() {}
104
105    public void message(Environment dbenv, String message)
106    {
107        // Put your special message handling code here
108    }
109
110}</pre>
111      <p>
112        And then set up your database to use the message handler by identifying
113        it on the database's <code class="classname">DatabaseConfig</code> object:
114    </p>
115      <a id="java_db11"></a>
116      <pre class="programlisting">package db.GettingStarted;
117
118import com.sleepycat.db.DatabaseConfig;
119
120...
121
122DatabaseConfig myDbConfig = new DatabaseConfig();
123MyMessageHandler mmh = new MyMessageHandler();
124myDbConfig.setMessageHandler(mmh); </pre>
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