java - Spring Boot - 出现意外错误(类型=错误请求，状态=400)。缺少必需的请求正文

Question

我创建了一个简单的 Spring Boot REST 服务来处理来自 HTML 页面的发布数据。当我发布数据时一切正常，但是当我想检查 @RequestMapping value href 上的数据时，我看到错误消息:

Whitelabel Error Page

This application has no explicit mapping for /error, so you are seeing this as a fallback.

Wed Nov 15 13:33:46 CET 2017 There was an unexpected error (type=Bad Request, status=400). Required request body is missing: public org.springframework.http.ResponseEntity> pl.sample.atms.web.rest.QuestionRestController.getQuestions5(pl.sample.atms.dto.Question)

如何查看并获取发送的数据？我的代码:

JS:

$.ajax({
    url: 'http://localhost:8080/api/questionsPost',
    dataType: 'json',
    type: 'post',
    contentType: 'application/json',
    data: JSON.stringify(scoreObj),
    success: function( data, textStatus, jQxhr ){
        console.log(data, textStatus, jQxhr)
    },
    error: function( jqXhr, textStatus, errorThrown ){
        console.log( jqXhr, textStatus, errorThrown );
    }
}); 

休息 Controller :

package pl.sample.atms.web.rest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import pl.sample.atms.dao.QuestionRepository;
import pl.sample.atms.dto.Question;
import java.util.ArrayList;
import java.util.List;

@RestController
@RequestMapping(value = "/api",  method = {RequestMethod.GET, RequestMethod.POST})
public class QuestionRestController {

    @Autowired
    private QuestionRepository questionRepository;

    @PostMapping("/questionsPost")
    public ResponseEntity<List<Question>> getQuestions5(@RequestBody Question myQuestion) {
        System.out.println(ResponseEntity.ok(new ArrayList<>()));
        System.out.println(myQuestion);
        return ResponseEntity.ok(new ArrayList<>());
    }

}

问题dto

package pl.sample.atms.dto;

import javax.persistence.Entity;
import javax.persistence.Id;

@Entity
public class Question {

    @Id
    private Long id;

    private String title;

    public Question() {
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }
}

问题库

package pl.sample.atms.dao;

import org.springframework.data.repository.CrudRepository;
import pl.sample.atms.dto.Question;

import java.util.List;

public interface QuestionRepository extends CrudRepository<Question, Long> {
    List<Question> findByTitle(String title);
}

更新

我更改了 Rest Controller 代码:

package pl.sample.atms.web.rest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.*;
import pl.sample.atms.dao.QuestionRepository;
import pl.sample.atms.dao.UserInfoRepository;
import pl.sample.atms.dto.Question;
import pl.sample.atms.dto.QuestionAnswer;
import pl.sample.atms.dto.Response;
import pl.sample.atms.dto.UserInfo;

import java.util.ArrayList;
import java.util.List;

import static org.apache.commons.lang3.StringUtils.isBlank;

@RestController
@RequestMapping("/api")
public class QuestionRestController {

    @Autowired
    private QuestionRepository questionRepository;

    @Autowired
    private UserInfoRepository userInfoRepository;

    private List<Question> question = new ArrayList<Question>();

    @GetMapping(value = "/questionsGet")
    public Response getResource() {
        Response response = new Response("Done", question);
        return response;
    }

    @PostMapping(value = "/questionsPost")
    public Response postCustomer(@RequestBody Question oneQuestion) {
        question.add(oneQuestion);

        Response response = new Response("Done", oneQuestion);
        return response;
    }

}

我创建了新类(class) - 响应:

package pl.sample.atms.dto;

public class Response {
    private String status;
    private Object data;

    public Response(){

    }

    public Response(String status, Object data){
        this.status = status;
        this.data = data;
    }

    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }
}

现在我可以看到一些发送的数据，但不幸的是它不是使用 JavaScript JSON 生成和发送的，但是:

{"status":"Done","data":[{"id":null,"title":null}]}

我需要的JSON结构:

"{"N":["4","4","5","4","2"],"E":["4","4","5","3","1"],"O":["3","3","4","2","3"],"U":["2","2","2","2","4"],"S":["3","2","2","3","3"]}"

我真的不知道我做错了什么，但我觉得我已经接近解决这个问题了。

Answer 1

使用 @PostMapping 注释时，您将方法限制为仅 POST 请求。

这相当于:

@RequestMapping(value = "/questionsPost", method = RequestMethod.POST)

如果你想同时接受POST和GET，我会将其更改为:

@RequestMapping(value = "/questionsPost")

该值表明一个 Post 请求 -> 因此，我个人会将其调整为“/questions”。

更新根据您对要完成的任务的评论，我强烈建议您使用两种单独的方法。如果您正在发布数据或尝试获取数据，Spring 将知道要调用哪个方法。然后相应地调整您的业务逻辑。

一种发布方法:

@RequestMapping(value = "/questions", method = RequestMethod.POST)

一种获取方法:

@RequestMapping(value = "/questions", method = RequestMethod.GET)