code: public String getStepNS(int opPosOfStep)
    {
  
      int argLenOfStep = getArgLengthOfStep(opPosOfStep);
  
      // System.out.println("getStepNS.argLenOfStep: "+argLenOfStep);
      if (argLenOfStep == 3)
      {
        int index = m_opMap.elementAt(opPosOfStep + 4);
  
        if (index >= 0)
          return (String) m_tokenQueue.elementAt(index);
        else if (OpCodes.ELEMWILDCARD == index)
          return NodeTest.WILD;
        else
          return null;
      }
      else
        return null;
    }
docs: Get the namespace of the step.
  
  @param opPosOfStep The position of the FROM_XXX step.
  
  @return The step's namespace, NodeTest.WILD, or null for null namespace.