package org.lcsim.util.log;
   
   import java.io.PrintWriter;
   import java.io.StringWriter;
   import java.util.logging.Formatter;
   import java.util.logging.LogRecord;
   
   /**
    * A log <code>Formatter</code> that prints only the message and error tracebacks.
   *
   * @author Jeremy McCormick <jeremym@slac.stanford.edu>
   */
  public class MessageOnlyLogFormatter extends Formatter {
  
      /**
       * Class constructor.
       */
      public MessageOnlyLogFormatter() {
      }
  
      /**
       * Format the <code>LogRecord</code> for printing
       *
       * @param record the <code>LogRecord</code> to format
       */
      @Override
      public String format(final LogRecord record) {
          final StringBuilder sb = new StringBuilder();
  
          // Append the message.
          sb.append(formatMessage(record) + '\n');
  
          // Append a traceback if there was an error thrown.
          if (record.getThrown() != null) {
              try {
                  final StringWriter sw = new StringWriter();
                  final PrintWriter pw = new PrintWriter(sw);
                  record.getThrown().printStackTrace(pw);
                  pw.close();
                  sb.append(sw.toString());
              } catch (final Exception ex) {
              }
          }
          return sb.toString();
      }
  }