Spring MVC ModelAttribute字段是空的而不是表单输入值

Question

我正在尝试制作一个发布CardRequestResource的表单:

public class CardRequestResource extends ResourceSupport{
    private Long cardRequestId;
    private String deliveryMethod;
    private String address;
    private boolean isHomeDelivery;
    private String requestDate;
    private String expectedDate;
    private String comments;
    private Long statusId;
    private PersonResource person;

    //Getters and Setters
}

在我的控制器中,我首先加载JSP并将一个空的CardRequestResource添加到ModelMap:

@RequestMapping(value = { "", "/approval" }, method = RequestMethod.GET)
public String getApproval(ModelMap map) {
    map.put("cardRequestResource", new CardRequestResource());       
    return "cardoffice/approval";
}

我的JSP使用cardRequestResource模型属性构建表单:

<form:form id="detailForm" name="detailForm" modelAttribute="cardRequestResource">
    <form:input path="statusId" type="hidden" id="statusId" name="statusId" />
    <form:textarea path="comments" name="comments" id="commentTextarea" rows="7" cols="81" style="font-style: normal;"/>
</form:form>

Javascript函数进行AJAX调用以填充表单值:

function getCardRequestDetails(cardRequestUrl) {
    $.ajax({
        type : "GET",
        url : cardRequestUrl,
        dataType : "json",
        success : function(response) {
            loadCardRequestDetails(response);
        },
        error : function(response) {}
    });
};

function loadCardRequestDetails(cardRequest) {
    $("#statusId").attr("value", cardRequest.statusId);
    $("#commentTextarea").val(cardRequest.comments);
}

此时,用户可以更新评论文本区域,并且隐藏的输入可以有条件地改变用户在该字段中输入的内容.然后在提交表单时,我调用以下Javascript函数:

function postCardRequest(url) {
    var serialized = $("#detailForm").serialize();
    alert(serialized);
    $.ajax({
        type: "POST",
        url: url,
        data: serialized,
        contentType: "application/json",
        dataType: "json"                
    });
}

警报显示字段使用最初由AJAX/Javascript或用户加载的数据正确填充.但是,当我到达处理帖子的控制器中的处理程序时,CardRequestResource为非null,但其中的EVERY SINGLE字段为NULL!

处理程序代码:

@RequestMapping(value = "/approval/submit", method = RequestMethod.POST)
public @ResponseBody Map<String, Object> postCardRequest(@ModelAttribute(value = "cardRequestResource") CardRequestResource cardRequestResource) {
    Map<String, Object> responseMap = new HashMap<String, Object>();
    final String success = "success";
    Boolean isSuccessful = Boolean.FALSE;

    if(cardRequestResource != null){
        isSuccessful = Boolean.TRUE;
    }
    //TODO

    System.out.println("Status: " + cardRequestResource.getStatusId() + ", Comments: " + cardRequestResource.getComments());

    responseMap.put(success, isSuccessful);
    return responseMap;
}

Answer 1

所以我想我找到了perp!

这个小伙伴就在POST AJAX电话中:

contentType: "application/json",

我最初将JSON发送到我的控制器,然后我了解到Spring MVC有那个漂亮的ModelAttribute注释,所以我不必担心在POST期间转换为/从JSON转换.不幸的是,我没有考虑删除那个contentType行,并且人们会认为它会抛出错误或其中的某些东西仍在那里......显然不是.绑定中的NULL值和无效调试的小时数...

删除该行后,我开始在CardRequest属性中获取数据而不是NULL!