从jsf重定向?

我正在为我的大学项目使用jsp、jstl和jsf开发应用程序,也就是说,我对jsf还很陌生。

到目前为止一切都很顺利。然而,我似乎有一个问题,即如何使用双戊基参数从托管bean重定向到页面。 例如 article.jsp?article_id=2

有人能告诉我这是怎么做的吗?

我试着用一些类似的东西

FacesContext.getCurrentInstance().getExternalContext().dispatch("faces/article.jsp2?article_id=" + articleId);

但得到错误:

javax.servlet.ServletException: #{postComment.postClick}: javax.faces.FacesException: javax.servlet.ServletException: javax.faces.component.UIViewRoot cannot be cast to com.sun.faces.application.StateManagerImpl$TreeNode
    javax.faces.webapp.FacesServlet.service(FacesServlet.java:256)

我一直想用

response.sendRedirect("faces/article.jsp2?article_id=" + articleId);
            return;

但又犯了个错误。

javax.servlet.ServletException: Cannot forward after response has been committed
    javax.faces.webapp.FacesServlet.service(FacesServlet.java:256)

有人能告诉我在使用JSF时如何从托管Java bean重定向吗?

下面是我的代码(可能有什么问题,这就是为什么重定向不工作)。

HttpServletRequest request = (HttpServletRequest) FacesContext.getCurrentInstance().getExternalContext().getRequest();
        HttpServletResponse response = (HttpServletResponse) FacesContext.getCurrentInstance().getExternalContext().getResponse();

        String articleId = request.getSession().getAttribute("article_id").toString();
        //String articleId  = request.getParameter("article_id");
        String authorName = request.getSession().getAttribute("user_name").toString();

        java.util.Calendar calendar = java.util.Calendar.getInstance();
        String commentDate = String.valueOf(calendar.get(java.util.Calendar.DAY_OF_MONTH)) + ".";
        commentDate += String.valueOf(calendar.get(java.util.Calendar.MONTH)) + ".";
        commentDate += String.valueOf(calendar.get(java.util.Calendar.YEAR));

         ArrayList error = new ArrayList();

        if(commentName.contains("<"))
        {
            error.add("Comment name contains illegal characters");
        }

        if(commentBody.isEmpty() && commentBody.contains("<script"))
        {
            error.add("Your message body contains illegal characters");
        }

        if(error.size() > 0)
        {
            request.getSession().setAttribute("error", error);
            error.clear();
            FacesContext.getCurrentInstance().getExternalContext().dispatch("article.jsp2?article_id=" + articleId);
        }
        else
        {
            Comment comment = new Comment();
            comment.setCommentAuthor(authorName);
            comment.setCommentBody(commentBody);
            comment.setCommentDate(commentDate);
            comment.setCommentName(commentName);
            comment.setArticleId(articleId);

            DisplayArticleIO addComment = new DisplayArticleIO();
            addComment.postComment(comment);
//            FacesContext.getCurrentInstance().getExternalContext().dispatch("faces/article.jsp2?article_id=" + articleId);
            response.sendRedirect("faces/article.jsp2?article_id=" + articleId);
            return;
        }

提前谢谢你。