Issue in deserializing JSONString into Java object containing list of Strings

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I have a JSONString as follows:


I have created a class Marks as follows:

public class Marks {
 private String attributeName;
 List<String> values;

While I am executing following line:

 List<Marks> markList = objectMapper.readValue(actionPriorityConfig, new TypeReference<Marks>());

I am getting following exception:

    com.fasterxml.jackson.databind.JsonMappingException: Can not 
   deserialize instance of out of START_ARRAY token
 at [Source: [{"values":["AA"],"attribute":"grade"},{"values":["mathematics"],"attribute":"subject"}]; line: 1, column: 1]

Can you try adding @JsonProperty("values") before the property values declaration.

public class Marks {
 private String attributeName;

 List<String> values;

Java and JSON – Jackson Serialization with ObjectMapper, Jackson - Serialize String to JSON Object A list of Java objects gets serialized to a list of JSON objects containing the fields and their values. You can parse a JSON array of Strings to a list in a very straightforward manner. 1 Answer 1. active oldest votes. 3. When you use JSON.deserializeUntyped(data), you need to perform type casting to tell the Apex compiler what kind of object you're working with or you'll get errors because the type Object has no property baseVolume (e.g.).

Seems like you're trying to convert it in a Mark objects, but items contains an array of Mark.

[Solved] How to convert Json string to list of objects, When you deserialise that JSON into that class it will look to put the Serialization classes, which will also need you to add some attributes to your classes, you won't have these fiddly issues, you'll be able to use your classes without Delphi / Pascal. F#. HTML / XML / ASP. Java. Kotlin. Javascript. SQL. Having trouble deserializing a data class represented as a JsonValue on toString and a single string arg constructor.. Am seeing the following error: com.fasterxml.jackson.databind.JsonMappingException: Can not instantiate value of type [simple type, class com.fasterxml.jackson.module.kotlin.test.StringValue] from String value ('test'); no

Your Json String valid but it is not a Json array.

Can you change the Json array to following format and check again.


Try following,

String actionPriorityConfig= "[{\"attribute\":\"grade\",\"values\":[\"AA\"]},{\"attribute\":\"subject\",\"values\":[\"mathematics\"]}]";
ObjectMapper objectMapper = new ObjectMapper();

List<Marks> markList = objectMapper.readValue(actionPriorityConfig, new TypeReference<Marks>());

Jackson – Convert JSON array string to List –, Few Jackson examples to convert a JSON array string to a List. // JSON array string readValue(json, Person[].class); // 2. convert JSON array to List of objects List<Person> ppl2 = Arrays. ObjectMapper; import Classes ObjectInputStream and ObjectOutputStream are high-level streams that contain the methods for serializing and deserializing an object. Below tutorial will work also if you have any of below questions: How to serialize and deserialize an object using JSON. How to serialize and deserialize an object in java example.

GSON - Parse JSON array to Java array or list, Learn to use Google GSON library to deserialize or parse JSON, containing json array, to java array or java list objects. Gson parse json array example. public void setName(String name) {. this .name = name;. } @Override Love computers​, programming and solving everyday problems. Find me on Facebook and Twitter​  Deserializing an Object in java. The opposite operation of the serialization is called deserialization i.e. to extract the data from a series of bytes is s known as deserialization which is also called inflating or unmarshalling. The given program shows how to read any data or contents from the serialized object or file.

Gson - Quick Guide, Learn to convert object to json; and convert json to java object. Also, it can used to convert the JSON string into equivalent java object. private List<String> roles; But, if you found any problem using a class having no-args constructor, you can to parse which contains JSON Arrays which I don't want, only the Objects. A class for deserializing a single JSON string into a C# on-the-fly object. - DynamicJson.cs

Gson, Getting Started with Java-JSON Serialization & Deserialization In the rest of the blog post, we'll name them object lists, but on the Java side they can be either. House", menu); Gson gson = new Gson(); String restaurantJson = gson.toJson(​restaurant);. The restaurantJson contains the following content: Gson can serialize a collection of arbitrary objects but can't deserialize the data without additional information. That's because there's no way for the user to indicate the type of the resulting object. Instead, while deserializing, the Collection must be of a specific, generic type. The correct way to deserialize the List would be:

  • It's valid only @SagarRohankar