Question

我的代码中有NumberFormatException。任何人都可以建议我如何克服这个问题？我正在尝试根据客户ID添加查询。客户ID是查询表中的连接列。当我点击添加查询链接时，我必须自动获取特定的ID。

@InitBinder
public void initBinder1(WebDataBinder binder) {
    binder.registerCustomEditor(Customer.class,"customer", new PropertyEditorSupport() {
         @Override
        public void setAsText(String customer) {
            setValue(new Customer(Integer.parseInt(customer)));
        }
    });
}

@RequestMapping(value="/addQuery.htm", method=RequestMethod.GET)
public ModelAndView reportForm1(ModelMap model,HttpServletRequest request) {
    int id=Integer.parseInt(request.getParameter("id"));
    System.out.println(id);

    Queries query = new Queries();
    Customer customer = new Customer(id);

    query.setCustomer(customer);
    model.addAttribute("queries", query);
    ModelAndView mav = new ModelAndView("addQuery");

    return mav;

}

这是我得到的错误：

Oct 14, 2014 12:25:32 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [dispatcherServlet] in context with path      
[/CustomerPortal] threw exception [Request processing failed; nested exception is    
java.lang.NumberFormatException: null] with root cause
java.lang.NumberFormatException: null
  at java.lang.Integer.parseInt(Unknown Source)
  at java.lang.Integer.parseInt(Unknown Source)
  at com.axiscapstone.customer.web.CustomerController.reportForm1(CustomerController.java:86)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
  at java.lang.reflect.Method.invoke(Unknown Source)

Answer 1

不要自己做这个转换。让Spring做到：

@RequestMapping(value="/addQuery.htm", method=RequestMethod.GET)
public ModelAndView reportForm1(@RequestParam Integer id, ModelMap model) {
    System.out.println(id);
    ...

但是id是Integer类型，当然可以为null。您可以使用@RequestParam(required = true)

强制客户端提供此URL参数

如何在我的控制器中修复NumberFormatException？

1 个答案: