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<chapter xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="JMS-Client-0-8-Logging">
  <title>Logging</title>
  <para>The Client uses the <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.slf4j.org">Apache SLF4J</link> logging
    framework. All logging activity created by the client is directed through the SLF4J API. SLF4J
    is a is a façade for other common logging frameworks. This makes it easy for application authors
    to use their prefered logging framework in their application stack, and have the Client
    use it too. </para>
  <para>SLF4J suppplies bindings for many common logging frameworks (<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="${oracleJdkDocUrl}java/util/logging/package-summary.html">JUL</link>, <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://logging.apache.org/log4j/1.2/">Apache Log4J</link>, <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://logback.qos.ch">Logback</link>.</para>
  <para>Include the SLF4J binding corresponding to the logging framework of your choosen logging
    framework on classpath. For full details, see the SLF4J <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.slf4j.org">documentation</link>.</para>

  <section xml:id="JMS-Client-0-8-Logging-RecommendedProductionLoggingLevel">
    <title>Recommended Production Logging Level</title>
    <para>In production, it is recommended that you configure your logging framework is configured
      with logger <literal>org.apache.qpid</literal> set to <literal>WARN</literal>.</para>
    <para>If you are using Apache Log4j with a log4j.properties file, this simply means adding the
      following line:</para>
    <screen>
      org.apache.qpid=WARN
    </screen>
    <para>If you are using another logging framework, or you are using Log4j but configuring in
      another manner, refer to the documentation accompanying the logging framework for details of
      how to proceed.</para>
  </section>
  <section xml:id="JMS-Client-0-8-Logging-EnablingDebugLogging">
    <title>Enabling Debug</title>
    <para>If you are experiencing a problem, it can be informative to enable debug logging to allow
      the behaviour of the Client to be understood at a deeper level.</para>
    <para>To do this, set the <literal>org.apache.qpid</literal> logger to
      <literal>DEBUG</literal>.</para>
    <para>If you are using Apache Log4j with a log4j.properties file, this simply means adding (or
      changing) the following line:</para>
    <screen>
      log4j.logger.org.apache.qpid=DEBUG
    </screen>
    <para>If you are using another logging framework, or you are using Log4j but configuring in
      another manner, refer to the documentation accompanying the logging framework for details of
      how to proceed.</para>
  </section>

</chapter>