Hello guys,
  I am using log4j for my web tier log system and feedback. I have this appender

    <appender name="EMAIL" class="org.apache.log4j.net.SMTPAppender">
        <param name="BufferSize" value="1" />
        <param name="From" value="admin at commercehub dot com" />
        <param name="To" value="hpathak at commercehub dot com" />
        <param name="Subject" value="Feedback" />
        <param name="SMTPHost" value="mail.commercehub.com" />
        <param name="LocationInfo" value="true" />
        <param name="EvaluatorClass" value="com.commercehub.log.CtiEmailEvaluator" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
                   value="%d %p (%F:%L) - %m%n"/>
        </layout>
    </appender>

Now for the parameter "Subject" I want to change its value dynamically. Right now for emails I get subject line "Feedback". I want some dynamic value to add to subject line... so it will be "Feedback -- abcdzyx".

Is that possible ?? Can I change its value dynamically ?

Please somebody help me.. thanks.

import com.commercehub.log.CtiEmailEvaluator;

      Logger _logger = Logger.getRootLogger();
      _logger.removeAllAppenders();

      CtiEmailEvaluator _eval = new CtiEmailEvaluator();
      
      SMTPAppender _smtp = new SMTPAppender(_eval);
      _eval.setSMTPAppender(_smtp);
      _smtp.setFrom("admin at commercehub dot com");
      _smtp.setTo("hpathak at commercehub dot com");
      _smtp.setSMTPHost("mail.commercehub.com");
      _smtp.setSubject("Feedback");
      _smtp.setLayout(new SimpleLayout()); //here use your PatternLayout
      _smtp.activateOptions();

      _logger.addAppender(_smtp);
      _logger.setLevel(Level.DEBUG);
      _logger.error("error");
      _logger.warn("warning");
      _logger.error("error");

Or just:

      import com.commercehub.log.CtiEmailEvaluator;

      Logger _logger = Logger.getRootLogger();
      SMTPAppender _smtp =
          (SMTPAppender) _logger.getAppender("EMAIL");

      _smtp.setSubject("Feedback");
      _smtp.activateOptions();

      _logger.removeAppender("EMAIL");
      _logger.addAppender(_smtp);

Thanks a lot.. Its working great.