javascript - spring4.3.7 How to obtain complex type parameters such as list passed by ajax

Question

spring4.3.7 How to receive complex types such as list passed by ajax?
It will be reported if it is passed directly

org.springframework.beans.InvalidPropertyException: Invalid property
'uAnswers0' of bean class [cn.xxx.entity.UAnswerList]:
Property referenced in indexed property path 'uAnswers0' is
neither an array nor a List nor a Map; returned value was
[cn.xxx.entity.UAnswer@2d3e47ed]

After searching for solutions on the Internet, they are basically from the past, mostly 3.x ones:

1. Add jackson jar package:

 jackson-core 

 jackson-mapper

 jackson-databind

2.Configuration xml

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list >
                <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter" />
            </list>
        </property>
    </bean>

One is that AnnotationMethodHandlerAdapter is abandoned, and the other is that it still reports an error and is told

org.springframework.web.util.NestedServletException: Request
processing failed; nested exception is
org.springframework.beans.InvalidPropertyException: Invalid property
'uAnswers0' of bean class [cn .xxx.entity.UAnswerList]:
Property referenced in indexed property path 'uAnswers0' is
neither an array nor a List nor a Map; returned value was
[cn.xxx.entity.UAnswer@70671304 ]

The detailed code is as follows:
1. UAnswer class

public class UAnswer {
    private Integer uaid;
    private Integer quid;//用户id
    private Integer qnid;//问卷id
    private Integer qid;//问题id
    private Integer oid;//选项id
    private String remark;//备注
    private String createtime;

    public Integer getUaid() {
        return uaid;
    }

    public void setUaid(Integer uaid) {
        this.uaid = uaid;
    }

    public Integer getQuid() {
        return quid;
    }

    public void setQuid(Integer quid) {
        this.quid = quid;
    }

    public Integer getQnid() {
        return qnid;
    }

    public void setQnid(Integer qnid) {
        this.qnid = qnid;
    }

    public Integer getQid() {
        return qid;
    }

    public void setQid(Integer qid) {
        this.qid = qid;
    }

    public Integer getOid() {
        return oid;
    }

    public void setOid(Integer oid) {
        this.oid = oid;
    }

    public String getRemark() {
        return remark;
    }

    public void setRemark(String remark) {
        this.remark = remark;
    }

    public String getCreatetime() {
        return createtime;
    }

    public void setCreatetime(String createtime) {
        this.createtime = createtime;
    }
}

2. UAnswerList class

public class UAnswerList {
    private Integer quid;//用户id
    private Integer qnid;//问卷id
    private List<UAnswer> uAnswers;

    public Integer getQuid() {
        return quid;
    }

    public void setQuid(Integer quid) {
        this.quid = quid;
    }

    public Integer getQnid() {
        return qnid;
    }

    public void setQnid(Integer qnid) {
        this.qnid = qnid;
    }

    public List<UAnswer> getuAnswers() {
        return uAnswers;
    }

    public void setuAnswers(List<UAnswer> uAnswers) {
        this.uAnswers = uAnswers;
    }
}

3、controller

    @ResponseBody
    @RequestMapping("addAnswer.do")
    public String addAnswer(HttpServletRequest request, HttpServletResponse response, UAnswerList uAnswers){
        ReturnResult r = new ReturnResult();
        r.setCode(1);
        r.setMsg("findAllNowCity success");
        if(uAnswers==null||uAnswers.getQnid()==null||uAnswers.getQuid()==null||uAnswers.getuAnswers()==null){
            r.setCode(-1);
            r.setMsg("尚未填写问卷");
            return r.toJsonString();
        }
         //相关操作
        return r.toJsonString();
    }

4. Ajax simulated data

function yaya(){
              $.ajax({
                    url: "http://192.168.0.251:8080/jsapi/addAnswer.do",
        
                    data:  {
                        quid:"odeq5uFtR835lZGTKxLpGy9jHEDU",
                        qnid:1,
                        uAnswers:[
                            {
                                qid:1,
                                oid:2
                            },
                            {
                                qid:1,
                                oid:3
                            },
                            {
                                qid:2,
                                oid:7
                            },
                            {
                                qid:3,
                                oid:14
                            },
                            {
                                qid:6,
                                oid:15,
                                remark:"hahaha"
                            },
                        ]
                        
                    },
                    type: "post",
        
                    cache : false,
        
                    dataType:'json',
        
                    success: function(data) {
                        console.log(data);
                        document.getElementById("resurl").innerHTML=  JSON.stringify(data);
        
                    },
            });
      }

It may also be a problem with the ajax data splicing format, but I don’t know how to solve it for the time being. .

Answer 1

Use @RequestBody UAnswerList uAnswers

Answer 2

    @ResponseBody
    @RequestMapping("addAnswer.do")
    public String addAnswer(HttpServletRequest request, HttpServletResponse response, @RequestBody UAnswerList uAnswers){
        ReturnResult r = new ReturnResult();
        r.setCode(1);
        r.setMsg("findAllNowCity success");
        if(uAnswers==null||uAnswers.getQnid()==null||uAnswers.getQuid()==null||uAnswers.getuAnswers()==null){
            r.setCode(-1);
            r.setMsg("尚未填写问卷");
            return r.toJsonString();
        }
         //相关操作
        return r.toJsonString();
    }

Answer 3

2 places need to be modified:

1. Use the @RequestBody annotation to indicate the use of http body content, as follows:

@ResponseBody
@RequestMapping("addAnswer.do")
public String addAnswer(HttpServletRequest request, HttpServletResponse response, @RequestBody UAnswerList uAnswers){ 省略 }

1. The js side needs to use json to transmit data, so you need to specify the application/json type and use JSON.stringify to convert the object into json format, as follows:

function yaya(){
              $.ajax({
                    url: "http://192.168.0.251:8080/jsapi/addAnswer.do",
                    contentType:"application/json",  //新增
                    data:  JSON.stringify({
                        quid:"odeq5uFtR835lZGTKxLpGy9jHEDU",
                        qnid:1,
                        uAnswers:[
                            {
                                qid:1,
                                oid:2
                            },
                            {
                                qid:1,
                                oid:3
                            },
                            {
                                qid:2,
                                oid:7
                            },
                            {
                                qid:3,
                                oid:14
                            },
                            {
                                qid:6,
                                oid:15,
                                remark:"hahaha"
                            },
                        ]
                        
                    }),
                    type: "post",
        
                    cache : false,
        
                    dataType:'json',
                   
                    success: function(data) {
                        console.log(data);
                        document.getElementById("resurl").innerHTML=  JSON.stringify(data);
        
                    },
            });
      }