$.ajax({
  type: "GET",
  url: "/user/add",
  dataType: "json",
  success: function(data){
    alert("添加成功");
  }
});

try {
  // do something
} catch (Exception e) {
  e.printStackTrace();
}

$.ajax({
  type: "GET",
  url: "/goods/add",
  dataType: "json",
  success: function(data) {
    if (data.flag) {
      alert("添加成功");
    } else {
      alert(data.message);
    }
  },
  error: function(data){
    alert("添加失敗");
  }
});

@RequestMapping("/goods/add")
@ResponseBody
public Map add(Goods goods) {
  Map map = new HashMap();
  try {
    // do something
    map.put(flag, true);
  } catch (Exception e) {
    e.printStackTrace();
    map.put("flag", false);
    map.put("message", e.getMessage());
  }
  reutrn map;
}

public class ResultBean<T> {
  private int code;
  private String message;
  private Collection<T> data;

  private ResultBean() {

  }

  public static ResultBean error(int code, String message) {
    ResultBean resultBean = new ResultBean();
    resultBean.setCode(code);
    resultBean.setMessage(message);
    return resultBean;
  }

  public static ResultBean success() {
    ResultBean resultBean = new ResultBean();
    resultBean.setCode(0);
    resultBean.setMessage("success");
    return resultBean;
  }

  public static <V> ResultBean<V> success(Collection<V> data) {
    ResultBean resultBean = new ResultBean();
    resultBean.setCode(0);
    resultBean.setMessage("success");
    resultBean.setData(data);
    return resultBean;
  }

  // getter / setter 略
}

@RequestMapping("/goods/add")
@ResponseBody
public ResultBean<Goods> getAllGoods() {
  List<Goods> goods = goodsService.findAll();
  return ResultBean.success(goods);
}

@RequestMapping("/goods/update")
@ResponseBody
public ResultBean updateGoods(Goods goods) {
  goodsService.update(goods);
  return ResultBean.success();
}

{
  "code": 0,
  "message": "success",
  "data": [
    {
      "name": "商品1",
      "price": 50.00,
    },
    {
      "name": "商品2",
      "price": 99.99,
    }
  ]
}

{
  "code": -1,
  "message": "XXX 參數(shù)有問題, 請(qǐng)重新填寫",
  "data": null
}

/**
 * 顯示錯(cuò)誤信息
 * @param result： 錯(cuò)誤信息
 */
function showError(s) {
  alert(s);
}

/**
 * 處理 ajax 請(qǐng)求結(jié)果
 * @param result： ajax 返回的結(jié)果
 * @param fn： 成功的處理函數(shù) ( 傳入data: fn(result.data) )
 */
function handlerResult(result, fn) {
  // 成功執(zhí)行操作，失敗提示原因
  if (result.code == 0) {
    fn(result.data);
  }
  // 用戶操作異常, 這里可以對(duì) 1 或 2 等錯(cuò)誤碼進(jìn)行單獨(dú)處理, 也可以 result.code > 0 來粗粒度的處理, 根據(jù)業(yè)務(wù)而定.
  else if (result.code == 1) {
    showError(result.message);
  }
  // 系統(tǒng)異常, 這里可以對(duì) -1 或 -2 等錯(cuò)誤碼進(jìn)行單獨(dú)處理, 也可以 result.code > 0 來粗粒度的處理, 根據(jù)業(yè)務(wù)而定.
  else if (result.code == -1) {
    showError(result.message);
  }
  // 如果進(jìn)行細(xì)粒度的狀態(tài)碼判斷, 那么就應(yīng)該重點(diǎn)注意這里沒出現(xiàn)過的狀態(tài)碼. 這個(gè)判斷僅建議在開發(fā)階段保留用來發(fā)現(xiàn)未定義的狀態(tài)碼.
  else {
    showError("出現(xiàn)未定義的狀態(tài)碼:" + result.code);
  }
}

/**
 * 根據(jù) id 刪除商品
 */
function deleteGoods(id) {
  $.ajax({
    type: "GET",
    url: "/goods/delete",
    dataType: "json",
    success: function(result){
      handlerResult(result, deleteDone);
    }
  });
}

function deleteDone(data) {
  alert("刪除成功");
}

@ControllerAdvice
@ResponseBody
public class WebExceptionHandler {

  private static final Logger log = LoggerFactory.getLogger(WebExceptionHandler.class);

  @ExceptionHandler
  public ResultBean unknownAccount(UnknownAccountException e) {
    log.error("賬號(hào)不存在", e);
    return ResultBean.error(1, "賬號(hào)不存在");
  }

  @ExceptionHandler
  public ResultBean incorrectCredentials(IncorrectCredentialsException e) {
    log.error("密碼錯(cuò)誤", e);
    return ResultBean.error(-2, "密碼錯(cuò)誤");
  }

  @ExceptionHandler
  public ResultBean unknownException(Exception e) {
    log.error("發(fā)生了未知異常", e);
    // 發(fā)送郵件通知技術(shù)人員.
    return ResultBean.error(-99, "系統(tǒng)出現(xiàn)錯(cuò)誤, 請(qǐng)聯(lián)系網(wǎng)站管理員!");
  }
}