code: public long getPollHeartbeatInterval() {
  
          int  retries  = getPollHeartbeatRetries();
          long interval = 10 + (HEARTBEAT_INTERVAL_PADDED / retries);
  
          try {
              interval = Long.getLong(POLL_INTERVAL_PROPERTY,
                                      interval).longValue();
          } catch (Exception e) {}
  
          if (interval <= 0) {
              interval = 10 + (HEARTBEAT_INTERVAL_PADDED / retries);
          }
  
          return interval;
      }
docs: Retrieves the interval, in milliseconds, that <tt>pollHeartbeat</tt>
  waits between failed invocations of <tt>checkHeartbeat</tt>.
  
  The value is obtained in the following manner: <p>
  
  <ol>
  <li>interval is assigned <tt>10 + (HEARTBEAT_INTERVAL_PADDED
  getPollHeartbeatRetries())</tt>
  
  <li>interval is assigned <tt>Long.getLong(POLL_INTERVAL_PROPERTY,
  interval)</tt>, inside a try-catch block, to silently ignore any security
  exception.
  
  <li>If interval is less than or equal to zero (0), interval is reassigned
  <tt>10 + (HEARTBEAT_INTERVAL_PADDED / getPollHeartbeatRetries())</tt>
  </ol>
  
  @return the interval, in milliseconds, that <tt>pollHeartbeat</tt>
  waits between failed invocations of <tt>checkHeartbeat</tt>