我想(实际上我知道!)我在这里做错了什么。我试图将一些值填充到HashMap中,并将每个hasmap添加到将添加到JSON对象的列表中:
JSONObject json = new JSONObject();
try
{
Map address;
List addresses = new ArrayList();
int count = 15;
for (int i=0 ; i<count ; i++)
{
address = new HashMap();
address.put("CustomerName" , "Decepticons" + i);
address.put("AccountId" , "1999" + i);
address.put("SiteId" , "1888" + i);
address.put("Number" , "7" + i);
address.put("Building" , "StarScream Skyscraper" + i);
address.put("Street" , "Devestator Avenue" + i);
address.put("City" , "Megatron City" + i);
address.put("ZipCode" , "ZZ00 XX1" + i);
address.put("Country" , "CyberTron" + i);
addresses.add(address);
}
json.put("Addresses", addresses);
}
catch (JSONException jse)
{
}
response.setContentType("application/json");
response.getWriter().write(json.toString());
我的问题是,我知道这是返回一个字符串,我似乎无法解析(这就是问题所在)。我的问题是如何返回实际的JSON编码字符串(或者甚至应该这样做?),或者对于这种类型的问题,最好的攻击方法是什么。我使用的JavaScript如下:
function getReadyStateHandler(req)
{
// Return an anonymous function that listens to the
// XMLHttpRequest instance
return function ()
{
// If the request's status is "complete"
if (req.readyState == 4)
{
// Check that a successful server response was received
if (req.status == 200)
{
msgBox("JSON Response recieved...");
populateDatagrid(req.responseText.toJSON());
}
else
{
// An HTTP problem has occurred
alert("HTTP error: " + req.status);
}
}
}
}
请注意,JSON响应返回良好,但它是一个字符串。如有任何建议,不胜感激。我也对使用谷歌Gson持开放态度,但我对此没有太多了解。
成功了!我应该构建一个JSONObject
s的JSONArray
,然后将数组添加到最后的"Addresses"JSONObject
中。观察以下内容:
JSONObject json = new JSONObject();
JSONArray addresses = new JSONArray();
JSONObject address;
try
{
int count = 15;
for (int i=0 ; i<count ; i++)
{
address = new JSONObject();
address.put("CustomerName" , "Decepticons" + i);
address.put("AccountId" , "1999" + i);
address.put("SiteId" , "1888" + i);
address.put("Number" , "7" + i);
address.put("Building" , "StarScream Skyscraper" + i);
address.put("Street" , "Devestator Avenue" + i);
address.put("City" , "Megatron City" + i);
address.put("ZipCode" , "ZZ00 XX1" + i);
address.put("Country" , "CyberTron" + i);
addresses.add(address);
}
json.put("Addresses", addresses);
}
catch (JSONException jse)
{
}
response.setContentType("application/json");
response.getWriter().write(json.toString());
这起到了作用,并返回了有效且可解析的JSON。希望这对将来的其他人有所帮助。感谢您的帮助Marcel
我在Servlet中使用了如下所示的JSONObject。
JSONObject jsonReturn = new JSONObject();
NhAdminTree = AdminTasks.GetNeighborhoodTreeForNhAdministrator( connection, bwcon, userName);
map = new HashMap<String, String>();
map.put("Status", "Success");
map.put("FailureReason", "None");
map.put("DataElements", "2");
jsonReturn = new JSONObject();
jsonReturn.accumulate("Header", map);
List<String> list = new ArrayList<String>();
list.add(NhAdminTree);
list.add(userName);
jsonReturn.accumulate("Elements", list);
Servlet返回这个JSON对象,如下所示:
response.setContentType("application/json");
response.getWriter().write(jsonReturn.toString());
这个Servlet是使用AngularJs从浏览器调用的,如下所示
$scope.GetNeighborhoodTreeUsingPost = function(){
alert("Clicked GetNeighborhoodTreeUsingPost : " + $scope.userName );
$http({
method: 'POST',
url : 'http://localhost:8080/EPortal/xlEPortalService',
headers: {
'Content-Type': 'application/json'
},
data : {
'action': 64,
'userName' : $scope.userName
}
}).success(function(data, status, headers, config){
alert("DATA.header.status : " + data.Header.Status);
alert("DATA.header.FailureReason : " + data.Header.FailureReason);
alert("DATA.header.DataElements : " + data.Header.DataElements);
alert("DATA.elements : " + data.Elements);
}).error(function(data, status, headers, config) {
alert(data + " : " + status + " : " + headers + " : " + config);
});
};
该代码有效,并且在警报对话框中显示了正确的数据:
Data.header.status:成功
Data.header.FailureReason:无
Data.header.DetailElements:2
Data.Elements:逗号分隔的字符串值,即NhAdminTree、userName
我认为您想要做的是在JSON字符串返回XMLHttpRequest时将其返回为对象,对吗?
如果是这样的话,你需要评估字符串以将其转换为JavaScript对象-请注意,这可能是不安全的,因为你相信JSON字符串不是恶意的,因此执行它。最好你可以使用jQuery的parseJSON