java - Servlet 发送 400 错误数据

Question

我希望我的 servlet 返回带有数据的错误代码，以便客户端可以向用户指出请求出了什么问题。如果数据无效时出现异常:

catch (UnvaildInputException UIE) {
            UnvaildCodes unvaildCode = UIE.getUnvaildCode(); //code 1 for example
            System.out.println(unvaildCode.getKey() + "-" + unvaildCode.getValue()); //prints error key-val
            System.out.println(unvaildCode.getValue());
            response.getWriter().print(HttpServletResponse.SC_BAD_REQUEST +":"+unvaildCode.getValue()); //trying to write a string as data
            response.setStatus(HttpServletResponse.SC_BAD_REQUEST); //400
        }

现在在客户端(angularjs)我正在尝试访问数据:

httpService.sendPost(vm.details, '/some/url').then(function (response){
        $log.log(response);
        $log.log(response.data);
});

错误:

TypeError: Cannot read property 'data' of undefined
    at formDirectiveJS.js:91
    at angular.min.js:126
    at m.$eval (angular.min.js:140)
    at m.$digest (angular.min.js:137)
    at m.$apply (angular.min.js:141)
    at g (angular.min.js:93)
    at t (angular.min.js:98)
    at XMLHttpRequest.u.onload (angular.min.js:99)

Answer 1

您需要在错误处理程序中处理错误，而不是在成功处理程序中。

来自https://stackoverflow.com/a/35458437/1842905

$http.get(url)
.then(function (response) {
    console.log('get',response)
})
.catch(function (data) {
    // Handle error here
});