code: @Override
    public boolean isModified()
    {
      if (_depend == null) {
        return false;
      }
      
      if (_depend.isModified()) {
        if (log.isLoggable(Level.FINE))
          log.fine("class modified: " + _depend);
  
        return reloadIsModified();
      }
      else if (_sourcePath == null) {
        return false;
      }  
      else if (_sourcePath.getLastModified() != _sourceLastModified) {
        if (log.isLoggable(Level.FINE))
          log.fine("source modified time: " + _sourcePath +
                   " old:" + new Date(_sourceLastModified) +
                   " new:" + new Date(_sourcePath.getLastModified()));
  
        if (! compileIsModified()) {
          return false;
        }
        
        boolean isModified = reloadIsModified();
  
        return isModified;
      }
      else if (_sourcePath.length() != _sourceLength) {
        if (log.isLoggable(Level.FINE))
          log.fine("source modified length: " + _sourcePath +
                   " old:" + _sourceLength +
                   " new:" + _sourcePath.length());
  
        if (! compileIsModified()) {
          return false;
        }
  
        return reloadIsModified();
      }
      else {
        return false;
      }
    }
docs: Returns true if the source file has been modified.