code: public boolean check(final char c)
  	{
  		current = current.get(c);
  		if (current == null) {
  			reset();
  		}
  		return current.isKeyword();
  	}
docs: Checks whether the character is related to the currently used node. If
  the comparison fails the keyword tree will be reseted to its root node,
  otherwise the related node will replace the current node.
  
  @param c
  character
  @return TRUE if the current node contains a keyword FALSE otherwise