错误400--请求错误

Question

我有一个基于Spring Web model view controller（MVC）框架的项目。Spring Web模型-视图-控制器（MVC）框架的版本是3.2.8

我有这个控制器

@SuppressWarnings("unchecked")
    @RequestMapping(value = { "/books/store/product",
                  "/books/store/product/",
                  "/books/store/product/{productId}",
                  "/books/store/product/{productId}/" }, method = { RequestMethod.POST })
    public String saveProduct(@ModelAttribute("productForm") ProductForm productForm, 
                              @PathVariable Long productId,
            HttpServletRequest request, Model model) throws Exception {

..
}

这个URL一切正常：/books/store/product/232

但是对于这个/书籍/商店/产品/

我得到了这个错误：

错误400--请求错误

From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:

10.4.1 400 Bad Request

The request could not be understood by the server due to malformed syntax. The client SHOULD NOT repeat the request without modifications.

我试图将这个PathVariable（required=false）放入，但我得到了一个编译错误：注释类型PathVariable所需的属性未定义




Answer 1

如果您不总是需要productId。尝试使用查询参数并将其设置为可选<代码>必需=false

此url现在看起来像：

1. http://localhost:8080/books/store/product?productId=232
2. http://localhost:8080/books/store/product

像这样：

@SuppressWarnings("unchecked")
    @RequestMapping(value = { "/books/store/product",
                   }, method = { RequestMethod.POST })
    public String saveProduct(@ModelAttribute("productForm") ProductForm productForm,
 @RequestParam(value = "productId", required = false) Long productId,
            HttpServletRequest request, Model model) throws Exception {

..
}

希望有帮助。

Answer 2

这是因为服务总是在等待路径变量productId

因为您使用的是Spring 3，所以我建议您创建两个方法。一个带有路径变量，另一个不带路径变量。

 @RequestMapping(value = { "/books/store/product",
                  "/books/store/product/"}, method = { RequestMethod.POST })
    public String saveProduct(@ModelAttribute("productForm") ProductForm productForm,
            HttpServletRequest request, Model model) throws Exception {

..
}

 @RequestMapping(value = { "/books/store/product/{productId}",
                  "/books/store/product/{productId}/" }, method = { RequestMethod.POST })
    public String saveProduct(@ModelAttribute("productForm") ProductForm productForm, 
                              @PathVariable Long productId,
            HttpServletRequest request, Model model) throws Exception {

..
}

如果您使用的是Spring 4和Java 8，我建议您使用optional。

@PathVariable Optional<Long> productId