为什么我的服务器在春天响应状态为500（内部服务器错误）？

Question

我将（jsp）表单详细信息与其他一些数据一起传递给控制器​​（spring）。当服务器响应状态为500（内部服务器错误）时，在浏览器控制台中收到错误：

（无法加载资源：服务器响应状态为500（内部服务器错误））

var formElement = document.getElementById("formCccAddAccount");
    var formDetails = new FormData(formElement);
    var otherData = $('#formCccAddAccount').serialize();

        formDetails.append('appNumber', appNumber);
        formDetails.append('fileDetails', fileDetails);
        formDetails.append('formNumber', formNumber);
        formDetails.append('clientID', clientID);
        formDetails.append('accountSequenceNumber',accountSequenceNumber);
        formDetails.append('otherData', otherData); 

        if(datavalid==true){
        $.ajax({
            type : 'post',
            url : 'CorporateClientCreation/accountSave.html',
            data : formDetails,
            cache: false,
            contentType: false,
            processData: false,
            success : function(json) {
                var obj = JSON.parse(json);
                if (obj.substring(0, 1) == "1") {
                    var data = obj.substring(1);
                    $.msgBox({
                        title : "Error Message",
                        type : "error",
                        content : data
                    });
                } else {
                    var account=obj.split("_");
                    var replayMessage='';
                    if(status==0)
                        replayMessage='Saved Sucessfully';

                    $.msgBox({
                        title : "Message",
                        type : "info",
                        content : replayMessage
                    });

                }
            },
            error : function(e) {
                $.msgBox({
                    title : "Error",
                    type : "error",
                    content : "Error Calling Function"
                });
            }
        });
    }

我的控制器是：

@RequestMapping(value = "/CorporateClientCreation/accountSave", method = RequestMethod.POST)
public @ResponseBody
String saveAccounts(HttpSession session, 
        @RequestParam(value = "formNumber") int formNumber, 
        @RequestParam(value = "fileDetails") String fileDetails,
        @RequestParam(value = "clientID") String clientID,
        @RequestParam(value = "appNumber") String appNumber,
        @RequestParam(value = "accountSequenceNumber") String accountSequenceNumber,
         CorporateClientCreationValueObject valueObject
        ) {

    //code