code: public boolean setTimestamp(Date date) throws LockingException {
                  Validate.notNull(date);
  
                  if (isFieldLocked(EntryField.TIME)) {
                          if (!this.timestamp.equals(date)) {
                                  throw new LockingException(EntryField.TIME);
                          }
                          return false;
                  } else {
                          this.timestamp = date;
                          return true;
                  }
          }
docs: Sets the timestamp of the log entry ({@link #timestamp}).
  
  @param date the time to set.
  @return <code>true</code> if {@link #timestamp} was modified;<br>
  <code>false</code> otherwise.
  @throws LockingException if the field TIME is locked and the given
  timestamp differs from the current value of {@link #timestamp}.