Question

我是初学者。代码如下

@RestController
@RequestMapping("/channel")

public class ChannelController 
{
    @GetMapping("/getId/{participantId}/{walletType}")
    Map<String,Object> getChannelId(@PathVariable Integer participantId , @PathVariable Integer walletType ){
        return demoDAOImpl.getChannel(participantId, walletType);
    }
}

当我点击http://localhost:8080/channel/getId///时，它会返回默认的Whitelabel错误页面，其中包含

出现意外错误（type = Not Found，status = 404）。

我很困惑。我认为Spring MVC应该抛出MissingPathVariableException。为什么回复404响应，找不到资源？

Answer 1

您可以使用 @PathVariable(required = false) 并手动处理逻辑：

@RestController
@RequestMapping("/channel")
public class ChannelController 
{
    @GetMapping("/getId/{participantId}/{walletType}")
    Map<String,Object> getChannelId(@PathVariable(required = false) Integer participantId , @PathVariable(required = false) Integer walletType) {

        if (participantId == null) {
            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Participant is required");
        }

        if (walletType == null) {
            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Wallet type is required");
        }

        return demoDAOImpl.getChannel(participantId, walletType);
    }
}

Answer 2

根据您的网址映射：您不能将其留空，如＆＃34; /// ＆＃34;它必须是＆＃34; / number / number / ＆＃34;

即 http://localhost:8080/channel/getId/0/0/

Answer 3

我猜你要的是自定义异常。那么你需要的是提供一个处理程序，你只需简单地扩展抽象类ResponseEntityExceptionHandler并覆盖方法handleMissingPathVariable。

一个例子：

@Override
protected ResponseEntity<Object> handleMissingPathVariable(MissingPathVariableException ex, HttpHeaders headers,
        HttpStatus status, WebRequest request) {

    String error = ex.getParameter() + " parameter is missing";
    ErrorMessageHandler error =message(HttpStatus.BAD_REQUEST, ex.toString(), error) ;
    return new ResponseEntity<Object>(error, new HttpHeaders(), HttpStatus.BAD_REQUEST);

}

Spring Boot缺少一些路径变量，但返回404

3 个答案: