code: public boolean isWhitespace(int nodeHandle)
    {
    	int type = getNodeType(nodeHandle);
      Node node = getNode(nodeHandle);
    	if(TEXT_NODE == type || CDATA_SECTION_NODE == type)
      {
        // If this is a DTM text node, it may be made of multiple DOM text
        // nodes -- including navigating into Entity References. DOM2DTM
        // records the first node in the sequence and requires that we
        // pick up the others when we retrieve the DTM node's value.
        //
        // %REVIEW% DOM Level 3 is expected to add a "whole text"
        // retrieval method which performs this function for us.
        FastStringBuffer buf = StringBufferPool.get();
        while(node!=null)
        {
          buf.append(node.getNodeValue());
          node=logicalNextDOMTextNode(node);
        }
       boolean b = buf.isWhitespace(0, buf.length());
        StringBufferPool.free(buf);
       return b;
      }
      return false;
    }
docs: Determine if the string-value of a node is whitespace
  
  @param nodeHandle The node Handle.
  
  @return Return true if the given node is whitespace.