Question

我使用springbatch使用JSF调用jasper报告。问题是当调用方法时，facescontext总是为null，所以我可以得到会话。对于我读过的不同问题，我意识到问题是因为批处理不在JSF生命周期中。我可以创建facescontext的实例，这样我就可以得到会话信息了吗？我尝试制作一个FacesServlet，但我不确定在哪个时刻，我可以调用它，以及如何获取请求和响应信息。

  HttpServletResponse httpServletResponse = (HttpServletResponse) FacesContext.getCurrentInstance().getExternalContext().getResponse();
        httpServletResponse.addHeader("Content-disposition", "attachment; filename=" + nombreReporte + ".pdf");
        ServletOutputStream servletOutputStream = httpServletResponse.getOutputStream();
        JasperExportManager.exportReportToPdfStream(jasperPrint, servletOutputStream);
        FacesContext.getCurrentInstance().responseComplete();

Answer 1

这本书最古老的技巧。请参阅：Access FacesContext From servlet

Answer 2

我发布的代码是我用来从托管bean生成JasperReports的代码，它可以工作：

      public ServletContext getContext() {
        return (ServletContext)getFacesContext().getExternalContext().getContext();
    }

    public HttpServletResponse getResponse() {
        return (HttpServletResponse)getFacesContext().getExternalContext().getResponse();
    }

    public static FacesContext getFacesContext() {
        return FacesContext.getCurrentInstance();
    }

    public void generate() {
        HttpServletResponse response =           (HttpServletResponse)FacesContext.getCurrentInstance().getExternalContext().getResponse();
        ServletOutputStream outStream;

        try {
            outStream = response.getOutputStream();
        } catch (IOException e) {
            _logger.severe("IOException getting outputStream during report generation!!", e);
            e.printStackTrace();
        }
        ServletContext context = getContext();
        InputStream fs = context.getResourceAsStream("/Reports/" + jrxml);

//Following there is a lot of code for generating my custom reports
   ........................

//At the end
   FacesContext.getCurrentInstance().responseComplete();
}

如何创建facescontext的实例

2 个答案: