/*
   * (non-Javadoc)
   *
   * @see com.sun.el.parser.NodeVisitor#visit(com.sun.el.parser.Node)
   */
  public void visit(Node node) throws ELException {
    if (node instanceof AstFunction) {

      AstFunction funcNode = (AstFunction) node;

      if (this.fnMapper == null) {
        throw new ELException(MessageFactory.get("error.fnMapper.null"));
      }
      Method m = fnMapper.resolveFunction(funcNode.getPrefix(), funcNode.getLocalName());
      if (m == null) {
        throw new ELException(
            MessageFactory.get("error.fnMapper.method", funcNode.getOutputName()));
      }
      int pcnt = m.getParameterTypes().length;
      if (node.jjtGetNumChildren() != pcnt) {
        throw new ELException(
            MessageFactory.get(
                "error.fnMapper.paramcount",
                funcNode.getOutputName(),
                "" + pcnt,
                "" + node.jjtGetNumChildren()));
      }
    } else if (node instanceof AstIdentifier && this.varMapper != null) {
      String variable = ((AstIdentifier) node).getImage();

      // simply capture it
      this.varMapper.resolveVariable(variable);
    }
  }
  private static final Node createNodeInternal(String expr) throws ELException {
    if (expr == null) {
      throw new ELException(MessageFactory.get("error.null"));
    }

    Node n = (Node) cache.get(expr);
    if (n == null && (n = (Node) cache2.get(expr)) == null) {
      try {
        n = (new ELParser(new StringReader(expr))).CompositeExpression();

        // validate composite expression
        if (n instanceof AstCompositeExpression) {
          int numChildren = n.jjtGetNumChildren();
          if (numChildren == 1) {
            n = n.jjtGetChild(0);
          } else {
            Class type = null;
            Node child = null;
            for (int i = 0; i < numChildren; i++) {
              child = n.jjtGetChild(i);
              if (child instanceof AstLiteralExpression) continue;
              if (type == null) type = child.getClass();
              else {
                if (!type.equals(child.getClass())) {
                  throw new ELException(MessageFactory.get("error.mixed", expr));
                }
              }
            }
          }
        }
        if (n instanceof AstDeferredExpression || n instanceof AstDynamicExpression) {
          n = n.jjtGetChild(0);
        }
        if (cache.size() > SIZE) {
          cache2.clear();
          cache2.putAll(cache);
          cache.clear();
        }
        cache.put(expr, n);
      } catch (ParseException pe) {
        throw new ELException("Error Parsing: " + expr, pe);
      }
    }
    return n;
  }