如何将EL值赋给java

Question

我想将该对象（$ {categorys}）分配给ArrayList

这是jsp

<%

     ArrayList<Category> al =${categorys};

 %>        

这是控制器

@RequestMapping(value = "/cat", method = RequestMethod.GET)
public ModelAndView getTrancationHistory() {

    ArrayList<Category> allData = service.viewAllCategory();
    //handle your code here...
    System.out.println(allData);
  for (Category allData1 : allData) {
        System.out.println(allData1.getCategoryName());
    }


    ModelAndView modelAndView = new ModelAndView();
    modelAndView.setViewName("WEB-INF/views/cat");
    modelAndView.addObject("categorys", allData);
    return modelAndView;
}

Answer 1

您不能在jsp scriptlet中使用${}。你必须手动获取它。你应该尝试这样的事情;

<%
List<Category> al = (List<Category>) request.getAttribute("categorys");
%>

或

<%
List<Category> al = (List<Category>) pageContext.getAttribute("categorys", pageContext.REQUEST_SCOPE);
%>