Java; Jackson; Parsing the array of array json string

» java » Java; Jackson; Parsing the array of array json string

By : ctrinh

Date : November 28 2020, 04:01 AM

I think the issue was by ths following , You don't need to Result class, it is redundant. You need to parse it as List> because your json structure starts as array and contains another arrays.
Here is how you can parse your :

code :

ObjectMapper mapper = new ObjectMapper();
try {
    List<Result> responseList = mapper.readValue(
            Files.readAllBytes(Paths.get("test.json")),
            new TypeReference<List<List<Student>>>() {});

} catch (IOException e) {
    e.printStackTrace();
}

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Jackson parsing JSON containing an array of objects and array of maps w/ dynamic keys

By : Ricardo Ricarte

Date : March 29 2020, 07:55 AM

Hope this helps I have json like this: , Solution:

code :

public class MyCustomClass {
    @JsonProperty("users")
    public LinkedHashMap<String, User> users;

    @JsonProperty("jobs")
    public ArrayList<Job> jobs;
}

java json array parsing with Jackson

By : user3422684

Date : March 29 2020, 07:55 AM

around this issue I have the following json file , I want to share how I get that, maybe someone will use ...

code :

ObjectMapper mapper = new ObjectMapper();
JsonParser parser = mapper.getJsonFactory().createJsonParser(new File(ConfigurationManager.jsonfile));

JsonToken token = parser.nextToken();

if (token == null) {
    System.out.println("no json file");
}

if (!JsonToken.START_ARRAY.equals(token)) {
    System.out.println("Expected an array");
}   

while (!JsonToken.END_ARRAY.equals(parser.nextToken())) {   
    System.out.println(parser.readValueAsTree().toString()));

    // parse json object here
}       

parser.close();

JAVA Jackson Parsing JSON Response that Contains List/Array

By : y2w1y2

Date : March 29 2020, 07:55 AM

wish help you to fix your issue I'm trying to deserialize a JSON string but I keep running into JSON Mapping Exception. I've been scouring the internet but have had little luck. , Your JSON is malformed. As you can see from the error message:

code :

[Source: [{"user":{"userId":"fa6491aeb", ..........];

parsing JSON array of JSON objects using Jackson throws JSON Mapping Exception, how to fix?

By : Netho Goncalves

Date : March 29 2020, 07:55 AM

it fixes the issue This is my JSON : , Try below code.

code :

 try {

       JSONArray  jsonArray = new JSONArray(res);
       List<ShreyPojo> pojoList = new ArrayList<>();

       for(int i = 0; i < jsonArray.length(); i++)
       {
          //JSONObject jsonObject = jsonArray.getJSONObject(i);
            String jsonObject = jsonArray.getString(i);

          ShreyPojo obj = mapper.readValue(jsonObject,ShreyPojo.class); 

           pojoList.add(obj);
       }

   // Use ShreyPojo objects as per requirement

 } catch (Exception e)
 {
    Log.w("Exception = ","" + e.toString());
 }

Convert json array string to java object using jackson API

By : Yogesh

Date : March 29 2020, 07:55 AM

it should still fix some issue I have JSON string like below, and want to convert into Java object using jackson API. , This is the solution, works like charm:

code :

try {
                TypeFactory typeFactory = mapper.getTypeFactory();
                CollectionType collectionType = typeFactory.constructCollectionType(
                                                    List.class, Users.class);
                List<Users> usersList =  mapper.readValue(new File("list.json"), collectionType);     

            } catch (IOException e) {
                e.printStackTrace();
            }