尝试在Spring MVC控制器中将JSON映射到Java对象时,在Ajax请求上收到400 Bad Request。我已经检查了该主题中的大多数相关问题,但仍然无法使它起作用

Ajax调用和JSON:

$.ajax({
    type: "POST",
    url: "vocabulary/createVocabulary",
    contentType : 'application/json; charset=utf-8',
    data: {"vocabularyName" : "a",
    "vocabularyDescription" : "b"},


我的控制器:

@Service
@Controller
@RequestMapping(path="vocabulary")
public class VocabularyController {

@RequestMapping (path = "createVocabulary", method = RequestMethod.POST)
@ResponseBody String createVocabulary(@RequestBody VocabularyDTO vocabularyDTO){
    return "Success";
  }
}


我的Java对象:

public class VocabularyDTO {

private String vocabularyName;
private String vocabularyDescription;

public VocabularyDTO(){};

public String getVocabularyName() {
    return vocabularyName;
}

public void setVocabularyName(String vocabularyName) {
    this.vocabularyName = vocabularyName;
}

public String getVocabularyDescription() {
    return vocabularyDescription;
}

public void setVocabularyDescription(String vocabularyDescription) {
    this.vocabularyDescription = vocabularyDescription;
}
}


我使用Spring 4.2.5和Jackson:

...

def springVersion = "4.2.5.RELEASE"

repositories {
mavenCentral()
jcenter()
}

dependencies {

compile group: "org.springframework", name: "spring-core", version: "$springVersion"
compile group: "org.springframework", name: "spring-beans", version: "$springVersion"
compile group: "org.springframework", name: "spring-context", version: "$springVersion"
compile group: "org.springframework", name: "spring-aop", version: "$springVersion"
compile group: "org.springframework", name: "spring-web", version: "$springVersion"
compile group: "org.springframework", name: "spring-webmvc", version: "$springVersion"
compile group: "org.springframework.data", name: "spring-data-jpa", version: "1.9.4.RELEASE"

compile group: "com.fasterxml.jackson.core", name: "jackson-databind", version: "2.6.5"
compile group: "com.fasterxml.jackson.core", name: "jackson-core", version: "2.6.5"
compile group: "com.fasterxml.jackson.core", name: "jackson-annotations", version: "2.6.5"

...
}


我得到的错误:


  HTTP错误400
  访问/ ux / vocabulary / createVocabulary时出现问题。原因:
  错误的请求


此外,如果我从控制器中删除“ @RequestBody”注释,则会收到以下服务器响应:


  无法实例化[com.attila.vocabulary.ux.spring.vocabulary.DTO.VocabularyDTO]:未找到默认构造函数;嵌套的异常是java.lang.NoSuchMethodException:com.attila.vocabulary.ux.spring.vocabulary.DTO.VocabularyDTO。()


有人知道什么地方可能出问题吗?谢谢!

更新:
没有'@RequestBody'注释的选项现在实际上正在工作(这是我的一个愚蠢的错误,为什么以前没有这样做)-即不引发错误,但是没有将值传递给对象。

我希望它也可以修复注释,但是我还是会收到400错误。

最佳答案

使用@RequestBody时,您的代码无法正常工作,因为您的ajax请求未发送json对象。您需要使用JSON.stringify()序列化JavaScript对象,然后再发送它。为什么要在控制器上使用@Service?尝试:

$.ajax({
    type: "POST",
    url: "vocabulary/createVocabulary",
    contentType : 'application/json; charset=utf-8',
    data: JSON.stringify({"vocabularyName" : "a",
    "vocabularyDescription" : "b"}),


@Controller
@RequestMapping(path="vocabulary")
public class VocabularyController {

@RequestMapping (path = "createVocabulary", method = RequestMethod.POST, consumes=MediaType.APPLICATION_JSON_VALUE}
@ResponseBody String createVocabulary(@RequestBody VocabularyDTO vocabularyDTO){
    return "Success";
  }
}

10-08 11:05