现在在做的项目用到了SpringMVC框架，需要从前端angular接收请求的JSON数据，为了测试方便，所以直接先用AJAX进行测试，不过刚开始用平时用的ajax方法，提交请求会出现415或者400错误，经过研究，终于可以了，现在做个总结。
js代码：
function postSimpleData() {$.ajax({type: "POST",url: "Service/SimpleData",contentType: "application/json", //必须有dataType: "json", //表示返回值类型，不必须data: JSON.stringify({ 'foo': 'foovalue', 'bar': 'barvalue' }), //相当于 //data: "{'str1':'foovalue', 'str2':'barvalue'}",success: function (jsonResult) {alert(jsonResult);}});}function login(){$.ajax({url: "Service/login",type: "POST",contentType: "application/json",dataType: "json",data: JSON.stringify({MachineIP:"127.0.0.1",AppTag:"4",RequestInfo:{StaffCode:"",Password:"",StaffCard:"01411"},}),async: true,success: function(data) {var ss = JSON.stringify(data);$("#result").val(ss);console.log(ss);}});}function postEmployees() {$.ajax({type: "POST",url: "Service/Employees",contentType: "application/json",dataType: "json",data: JSON.stringify({ "Employees": [{ "firstName": "Bill", "lastName": "Gates" },{ "firstName": "George", "lastName": "Bush" },{ "firstName": "Thomas", "lastName": "Carter" }]}),success: function (jsonResult) {alert(jsonResult);}});}
JAVAController代码：
@RequestMapping(value = "/SimpleData", method = RequestMethod.POST)@ResponseBodypublic ActionResult SimpleData(string foo, string bar) {return Json("SimpleData", JsonRequestBehavior.AllowGet);}@RequestMapping(value = "/login", method = RequestMethod.POST)@ResponseBodypublic ResponseProtocolMap login(@RequestBody JSONObject requestJson, HttpServletRequest request) {ResponseProtocolMap responseProtocolMap = null;String machineIP = RequestJsonUtils.getMachineIP(requestJson);String appTag = RequestJsonUtils.getAppTag(requestJson);JSONObject requestInfo = RequestJsonUtils.getRequestInfo(requestJson);if (requestInfo == null) {responseProtocolMap = new ResponseProtocolMap("-1", "参数错误");} else {String staffCode = RequestJsonUtils.getValueByKey(requestInfo, "StaffCode");String password = RequestJsonUtils.getValueByKey(requestInfo, "Password");String staffCard = RequestJsonUtils.getValueByKey(requestInfo, "StaffCard");responseProtocolMap = sysLoginService.login(staffCode, password, staffCard, appTag, request);}return responseProtocolMap;}@RequestMapping(value = "/Employees", method = RequestMethod.POST)@ResponseBodypublic ActionResult Employees(List<Employee> Employees) {return Json("Employees", JsonRequestBehavior.AllowGet);}
public class Employee{public string FirstName { get; set; }public string LastName { get; set; }}
值得注意的有2点：
1）Ajax 选项中
contentType: "application/json"
这一条必须写，表明request的数据类型是json。
而
dataType: "json"
这一条表示返回值的类型，不是必须的，且依据返回值类型而定。
2）选项中
data: JSON.stringify({ 'foo': 'foovalue', 'bar': 'barvalue' })
很多时候我们将数据写作：
{ 'foo': 'foovalue', 'bar': 'barvalue' }
这样会导致错误，因为js会默认将这个json对象放到表单数据中，故而导致controller接收不到。
有两种办法处理：第一种方式是用JSON.stringify()函数，其中JSON被Ecmascript5定义为全局对象。
第二种方式是直接用双引号包裹起来，比如data: "{'str1':'foovalue', 'str2':'barvalue'}"。
