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Spring Boot - Returning JSON with map of list of object and another object

I made a RestController for bulletin board application. Firstly, I made a simple version without pagination logic as follows.
Request URL is:
http://localhost:8005/article => show article list(List<ArticleDto>)
I can make json response like this
public ResponseEntity<List<ArticleDto>> articleList(){
List<ArticleDto> list = articleService.list();
return new ResponseEntity<List<ArticleDto>>(list, HttpStatus.OK);
}
and I got this json.
[{"articleId":1, "title": "...", "content": "..."},
{"articleId":1, "title": "...", "content": "..."},
{"articleId":1, "title": "...", "content": "..."}, ...]
It is a really long list, so, I want to make a more complex version with pagenation info. But, I don't know how to make a json response with both article list and pagenation info because my response type is ResponseEntity<List<ArticleDto>>.
Request URL is:
http://localhost:8005/article?currentPage=1 => show 10 articles of first page(List<ArticleDto>) with pagenation(Pagination object).
public ?? articleList(#RequestParam(value="currentPage", required=false) String currentPage) throws Exception {
int itemsPerPage = 10;
int pagesPerGroup = 10;
if (currentPage == null || currentPage == "") currentPage = "1";
Map<String, String> map = new HashMap<String, String>();
map.put("currentPage", currentPage);
int totalItemCount = articleService.totalItemCount(map);
Pagination pagination = new Pagination(totalItemCount, itemsPerPage, pagesPerGroup, Integer.parseInt(currentPage));
map.put("offset", ""+pagination.getOffset());
map.put("limit", ""+pagination.getLimit());
List<ArticleDto> list = articleService.list(map);
return new ?? ( ?? , HttpStatus.OK);
}
I want to get a json return like this:
{
"articles": [{"articleId": 1, "title": "...", "content": "..."} ...],
"pagination": {
"currentPage": 1,
"totalItemCount": 121,
"itemsPerPage: 10,
"lastPage": 13,
...
}
}
I can do it very easily when I use express or laravel, but it is really hard in Java. I am new to Java, please help me.

Use a class to encapsulate the response.
class ArticleResponse{
List<ArticleDto> articles;
Pagination pagination;
}
Populate these values and then send the object back.

Spring Data JPA already provides an interface for Pagination.
You can read the documentation or review the javadocs.

Get data from outside the root level of response

I'm still kind of new to REST and haven't been able to figure this one out.
I have a response like this one:
{
"StatusCode": 200,
"Result": {
"CustomerStuff": {
"Name": "John",
"State": "Oregon",
"GetEmail": false
},
"eText": "Will only get paper mail. "
}
}
I would normally save the response body as a string and then use a JsonPath to get what I need.
String responseBody = given().body().when().etc...;
JsonPath jsonPath = new JsonPath(responseBody).setRoot("Result.CustomerStuff");
Then get what I need:
String name = jsonPath.get("name");
I can't figure out how to get the, "eText" value. It's not in the same segment of the response.
Any suggestions?

You should use
JsonPath jsonPath = new JsonPath(responseBody).setRoot("Result")
And then call jsonPath.get("eText") in order to get the value you want.
You can still access CustomerStuff with jsonPath.get("CustomerStuff")

Searching JSon string using java

I am new To JSon and i want to search the following json string and get the required output.
String:
{"status":"Success","code":"200","message":"Retrieved Successfully","reason":null,"
"projects":
[
{
"projectName": "example",
"users":
[
{
"userName": "xyz",
"executions":
[
{
"status": "check",
"runs":
[
{
"Id": "------",
"Key": "---"
}
],
"RCount": 1
}
],
"RCount": 1
}
],
"RCount": 1
},
Like that i have many projects and now , if i give projectname and username as input i wantt to get its status as output.
Is it possible?If yes how?

You may use JSONObject for this.
JSONObject json = new JSONObject(string);
JSONArray[] projectsArray = json.getJSONArray("projects");
for(int i = 0; i < projectsArray.length; ++i)
{
String projectName = projectsArray[i].getString("projectName");
...
}
Use the same method to get the users.

You can use gson library. Using gson convert your json string to Map and then you can iterate through map to get required item
Type type = new TypeToken<Map<String, Object>>(){}.getType();
Map<String, Object> myMap = gson.fromJson(jsonString, type);

You can use the Google gson to map your json data structure to a Java POJOs.
Example :
You can have Projects class containing list/array of Users.
Users class containing list/array of Executions and so on.
Gson library can easily map the json to these classes as objects and you can access your data in a more elegant manner.
Here are a few references :
http://howtodoinjava.com/2014/06/17/google-gson-tutorial-convert-java-object-to-from-json/
http://www.mkyong.com/java/how-do-convert-java-object-to-from-json-format-gson-api/

AngularJS: passing complex json data using $http.post

I'm having trouble passing a complex json object in angularjs with $http.post. I'm keep getting a 400 bad request error sent back from the server saying the request was syntactically incorrect. I believe it has something to do with the array since it passes fine when i don't include it.
json i'm passing.
{
customer: {
firstName: "John",
lastName: "Doe",
street: "1234 South Dr",
city: "Detroit",
state: "MI",
zip: "12345",
phone: "123-321-1234",
email: "EMAIL#GMAIL.COM"
},
order: {
orderDate: "06-16-2015",
registerNum: "1",
transactionNum: "7820",
deliveryStatusID: 1,
notes: "Hold order until July",
items: [
{skuID: "1234568",
skuDescription: "Order item 1",
qty: "4",
itemStatusID: 1,
itemStatusDescription: "Backorder"
},
{skuID: "7387491",
skuDescription: "Order item 2",
qty: "1",
itemStatusID: 1,
itemStatusDescription: "Flagged"
}
]
}
}
angular service function
this.addOrder = function(new_order) {
return $http.post(base + "/add", new_order);
};
Spring MVC controller method
#RequestMapping(value="/add", method=RequestMethod.POST)
public void addOrder(#RequestBody CustomerOrder customerOrder) {
System.out.println("----CUSTOMER-INFO----");
System.out.println(customerOrder.getCustomer().getFirstName());
System.out.println(customerOrder.getCustomer().getLastName());
System.out.println("");
System.out.println("----ORDER-INFO----");
System.out.println(customerOrder.getOrder().getOrderID());
System.out.println(customerOrder.getOrder().getOrderDate());
}
The problem only seems to occur when I pass the items array in the json. I've passed the same json object without the items array and it works fine. The format of the json is being sent in the same format that gets returned whenever I GET an order with my angularjs service method so I'm really not sure as to where I'm going wrong with this.
If I need to provide more code please let me know. I appreciate any effort in helping me out.
Thank you.
Jason

Well after struggling to find my error in this problem, I finally found a solution. I thought I'd share how I debugged and fix this problem in case someone else is in a similar situation as I was.
After trying every possible way of sending my data in angular to the server and continually getting the same HTTP 400 error, I decided to send the json as a string and accept the json as a string in my spring mvc controller like this.
angular service method:
this.addOrder = function(new_order) {
return $http.post(base + "/add", angular.toJson(new_order));
};
spring controller
#RequestMapping(value="/add", method=RequestMethod.POST, consumes="application/json")
public void addOrder(#RequestBody String json) {
}
From here I simply took the json passed in and used the Jackson ObjectMapper to convert the json string to my POJO like this.
mapping json string to pojo
#RequestMapping(value="/add", method=RequestMethod.POST, consumes="application/json")
public void addOrder(#RequestBody String json) {
ObjectMapper mapper = new ObjectMapper();
try {
CustomerOrder order = mapper.readValue(json, CustomerOrder.class);
System.out.println(order.getCustomer().getFirstName() + " " + order.getCustomer().getLastName());
} catch (JsonGenerationException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
After doing this and running my code, I would get an UnrecognizedPropertyException on a field in my Items class when trying to bind the items json to the List in my Order class. It was just a simple mispelling on the json side and I completely missed it. After correcting this, jackson mapped everything correctly and I no longer get this HTTP 400 Error The request was syntactically incorrect.
Another thing to note is that if you pass your object as a string in angular using the JSON.stringify you may encounter this same exception on hashKey field in the JSON object. The hashKeys are used by angular to monitor changes. I believe you can use a jackson annotation to ignore unknown fields or you can simply use angular.toJson instead which will remove all the hasKey/values for you which is what I did.

Just formatted the Json in a better way. Try this if it helps. Also, post the java classes if possible:
{
"customer": {
"firstName": "John",
"lastName": "Doe",
"street": "1234 South Dr",
"city": "Detroit",
"state": "MI",
"zip": "12345",
"phone": "123-321-1234",
"email": "EMAIL#GMAIL.COM"
},
"order": {
"orderDate": "06-16-2015",
"registerNum": "1",
"transactionNum": "7820",
"deliveryStatusID": 1,
"notes": "Hold order until July",
"items": [
{
"skuID": "1234568",
"skuDescription": "Order item 1",
"qty": "4",
"itemStatusID": 1,
"itemStatusDescription": "Backorder"
},
{
"skuID": "7387491",
"skuDescription": "Order item 2",
"qty": "1",
"itemStatusID": 1,
"itemStatusDescription": "Flagged"
}
]
}
}

Parse json string for specific value using JSONObject

In java, I am trying to parse values from this json..
[
{
"2012-01-02": {
"age": 3,
"dob": "2010-01-03",
"name": "jack"
},
"2012-01-03": {
"age": 3,
"dob": "2010-01-04",
"name": "jill"
},
"2012-01-04": {
"age": 3,
"dob": "2010-01-05",
"name": "john"
},
"2012-01-05": {
"age": 3,
"dob": "2010-01-06",
"name": "miran"
}
}
]
Using JSONObject, I was trying to get the value of just "age" and then add them up to do some data manipulation.
I created a JSONObject
Created an iterator and then stored them to a map
This gets me the inner element like:
{
"age": 3,
"dob": "2010-01-06",
"name": "miran"
}
After this, not sure how to extract just age from each element. Do i create another jsonobject and pass this new string, extract age out of it or is there a better way to do this? (I am sure there is one)
UPDATE:
This is what I currently have that gives me {"age":3,"dob":"2012-01-06","name":"miran"}
JSONObject jsonobj = new JSONObject();
try {
jsonobj = new JSONObject(pastweekVol);
Iterator iter = jsonobj.keys();
Map<String, String> map = new HashMap<String, String>();
while(iter.hasNext()){
String jsonkey = (String)iter.next();
String value = jsonobj.getString(jsonkey);
logger.debug("first pass value is: {}", value);
} catch (JSONException je) {
logger.debug("exception is: {}",je);
}
I was thinking that since I am getting {"age":3,"dob":"2012-01-06","name":"miran"}, I would create another json object and pass in this string, which will give me value of "age". The problem here is that I get repetitive values. Of course, something very basic is missing here but I can't seem to figure that out.

If you have the inner element as a JSONObject instance - say person - then you can directly access the age:
int age = person.getInt("age");
and do something with it:
sum += age;

You might consider a library like Google's GSON (http://code.google.com/p/google-gson/) if you want to be able to easily parse arbitrarily complex JSON strnigs into generic objects.

Using org.json is probably not your best bet -- this API has many flaws. Using Jackson, you can easily extract age from each member value:
ObjectMapper mapper = new ObjectMapper();
JsonNode fullDocument = mapper.readTree(xxx); // xxx can be many things
// Not an object? Bail out
if (!fullDocument.isObject())
throw new IllegalArgumentException("not an object");
// This will iterate through object values
for (JsonNode value: fullDocument)
// do something with value.get("age")
// in particular, you can test for .isIntegralNumber()