Spring MVC 3 - 可选的URL参数

Question

我写了以下代码：

@Controller
@RequestMapping("/page{number}")
public class IndexController
{ 
    @RequestMapping(method = RequestMethod.GET)
    public String printIndex(ModelMap model, @PathVariable int number)
    {
        String numberText;

        switch (number)
        {
            case 0:
                numberText = "Zero";
                break;
            case 1:
                numberText = "One";
                break;
            default:
                numberText = "Unknown";
                break;
        }

        model.addAttribute("number", numberText);

        return "page";
    }
}

而且我想要实现像此方法控制的page1.html，page2.html，page3.html这样的网址，但有一个例外：page.html应该给出与page1.html相同的结果。我正在寻找能使{number}成为可选项的东西，现在它是必需的。

我说有没有办法做到这一点？

/

Answer 1

这个怎么样：

@Controller
public class IndexController
{ 
    @RequestMapping("/page{number}")
    public String printIndex(ModelMap model, @PathVariable("number") int number)
    {
        String numberText;

        switch (number)
        {
            case 0:
                numberText = "Zero";
                break;
            case 1:
                numberText = "One";
                break;
            default:
                numberText = "Unknown";
                break;
        }

        model.addAttribute("number", numberText);

        return "page";
    }
    @RequestMapping("/page")
    public String printIndex(ModelMap model)
    {
        return printIndex(model, 1);
    }    
}

Answer 2

你可以使用这样的东西：

@RequestParam(value = "name", defaultValue = "") Long name

请记住，您必须使用包装器（如Long）而不是原始包装器（如长）。

我希望这会有用。

Answer 3

您可能想要实现自定义WebArgumentResolver和注释@OptionalPathVariable并自己处理它

Answer 4

Rest API - Optional Parameters and change values

@GetMapping(value = "/country/list")
public ResponseEntity<?> companyInformationList
(
Pageable pageable,
@RequestParam(name = "q", required = false,defaultValue = "") String q,
@RequestParam(name = "sortby", required = false, defaultValue = "companyId") String sortby,
@RequestParam(name = "order", required = false, defaultValue = "desc") String order,
@RequestHeader(value = "Accept-Language", defaultValue = "ar") String lang ) {


        if(sortby.equalsIgnoreCase("countryName")) {
            if(lang.equalsIgnoreCase("en")) {
                sortby="countryNameEn"; 
            }else
            if(lang.equalsIgnoreCase("ar")) {
                sortby="countryNameAr";
            }else
            if(lang.equalsIgnoreCase("fr")) {
                sortby="countryNameFr";
        }