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Java get specific data from dynamic JSONObject

I have a JSON String and convert it to JSONObject.
I want to get specific data from the JSONObject, and every time the JSONObject changes its structure, sometimes it's in an array inside the JSON and sometimes not.
example:
the first time the JSON arrives like this
{
"id": "1",
"Name": "Jack",
"Value": {
"data": [
{"time": "2023", "age": "22"}
]
}}
the second time
{
"age": "22",
"time": "2023",
"Value": {
"data": [
{"Name": "Jack", "id": "1" }
]
}}
if I want to get the name in the first JSON
jsonObject.getString("Name")
and for the second one, I would use
jsonObject.getJSONArray("data").getJSONObject(0).getString("Name")
is there a way I can get the value dynamically regardless of where the keys are?

If your API come from an another team or an external provider, the first thing I would suggest to you, is to clearly define a contract. Otherwise, you can use the isNull(String key) method of JSONObject to check if the key exists or not.
An example here:
JSONObject jsonObject = new JSONObject(YOUR_JSON_STRING);
String nameValue;
if(jsonObject.isNull("Name")) {
nameValue = jsonObject.getJSONObject("Value")
.getJSONArray("data")
.getJSONObject(0)
.getString("Name");
} else {
nameValue = jsonObject.getString("Name");
}
System.out.println(nameValue);

If the JSON strings are always in a similar fashion then you can try a little parser method as provided below. It returns a Key/Value (String/Object) Map:
public static java.util.Map<String, Object> mapJsonObject(String jsonString) {
String json = jsonString
.replaceAll("(?i)[\\[\\]\\{\\}\"]|\"?value\"?:|\"?data\"?:|\n?", "")
.replaceAll("\\s+", " ");
String[] keyValueParts = json.split("\\s*,\\s*");
java.util.Map<String, Object> map = new java.util.HashMap<>();
for (String str : keyValueParts) {
String[] pts = str.split("\\s*:\\s*");
map.put(pts[0].trim(), pts[1]);
}
return map;
}
To use:
String jsonString = "{\n"
+ " \"id\": \"1\",\n"
+ " \"Name\": \"Jack\",\n"
+ " \"Value\": {\n"
+ " \"data\": [\n"
+ " {\"time\": \"2023\", \"age\": \"22\"}\n"
+ " ]\n"
+ "}}";
java.util.Map<String, Object> map = mapJsonObject(jsonString);
System.out.println(map);
The console window will display:
{id=1, time=2023, age=22 , Name=Jack}

You may consider library Josson.
https://github.com/octomix/josson
Deserialization
Josson josson1 = Josson.fromJsonString(
"{" +
" \"id\": \"1\"," +
" \"Name\": \"Jack\"," +
" \"Value\": {" +
" \"data\": [" +
" {\"time\": \"2023\", \"age\": \"22\"}" +
" ]" +
" }" +
"}");
Josson josson2 = Josson.fromJsonString(
"{ " +
" \"age\": \"22\"," +
" \"time\": \"2023\"," +
" \"Value\": {" +
" \"data\": [" +
" {\"Name\": \"Jack\", \"id\": \"1\" }" +
" ]" +
" }" +
"}");
Query
*() is a multi-level wildcard search. It returns the first resolvable element.
System.out.println(josson1.getString("coalesce(Name, *().Name)"));
// Output: Jack
System.out.println(josson2.getString("coalesce(Name, *().Name)"));
// Output: ["Jack"]
// It is because "Name" is inside array "data".
System.out.println(josson1.getString("coalesce(Name, *().Name).first()"));
// Output: Jack
System.out.println(josson2.getString("coalesce(Name, *().Name).first()"));
// Output: Jack
// Added function first() to extract the value.

How to compare two JSON responses in java irrespective of JSON array sequence?

As per business need I have to compare JSON response of API URL , which suppose to be a generic solution.
JSON compare needs to be include value mismatch as well as schema mismatch too.
As per the requirement is to be a generic solution.
I can not create a java object as per the response and compare as response JSON can be anything with any schema ,so JSON to object convention is not possible as object structure can not be defined before hand and will change with each sets of API.
What I tried :
Try to implement
Approach 1) flipkart-incubator/zjsonpatch: This is an implementation of RFC 6902 JSON Patch written in Java (github.com)
Approach 2) https://github.com/wnameless/json-flattener
But with this implementation problem is that
but Main issue is that , all is doing case to case matching and able to handle mismatch in sequence in response.
Suppose API response of two API as follows for which I want to compare….
Response of API 1
{
"name": "name1",
"address": "",
"skillset": [
{
"lang": "java",
"projectName": "project1"
},
{
"lang": "c++",
"projectName": "project2"
}
]
}
Response of API 2 :
{
"name": "name1",
"address": "",
"skillset": [
{
"lang": "c++",
"projectName": "project2"
},
{
"lang": "java",
"projectName": "project1"
}
]
}
In this two JSON response , array element are same but they not matching index wise in skillset array.
My requirement is like this as for name "name1", as skillset is same (just the response order is different), I have to consider this as "no mismatch" in JSON response.
But the above two implementation showing it as mismatch in JSON response and in skill set array , sequence is different in both the response.
May be this can be easily done by json to java object conversion and then do the object compare. But as this is a generic solution and JSON response schema is not known beforehand so its not possible to create any object structure.
Any one can suggest any approach , tool or process through which this can be achieve? Mainly I need to do a json comparation irrespective of JSON array sequence.

https://github.com/octomix/josson
https://mvnrepository.com/artifact/com.octomix.josson/josson
This new library can do the job.
implementation 'com.octomix.josson:josson:1.3.20'
------------------------------------------------
ObjectMapper mapper=new ObjectMapper();
JsonNode api1 = mapper.readTree("{\n" +
"\"name\": \"name12\",\n" +
"\"address\": \"\",\n" +
"\"skillset\": [\n" +
" {\n" +
" \"lang\": \"java\",\n" +
" \"projectName\": \"project1\"\n" +
" },\n" +
" {\n" +
" \"lang\": \"c++\",\n" +
" \"projectName\": \"project2\"\n" +
" }\n" +
"]\n" +
"}");
JsonNode api2 = mapper.readTree("{\n" +
"\"name\": \"name12\",\n" +
"\"address\": \"\",\n" +
"\"skillset\": [\n" +
" \n" +
" {\n" +
" \"lang\": \"c++\",\n" +
" \"projectName\": \"project2\"\n" +
" },\n" +
" {\n" +
" \"lang\": \"java\",\n" +
" \"projectName\": \"project1\"\n" +
" }\n" +
"]\n" +
"}");
System.out.println(api1.equals(api2)); // -> false
Jossons jossons = new Jossons();
jossons.putDataset("api1", Josson.create(api1));
jossons.putDataset("api2", Josson.create(api2));
System.out.println(jossons.evaluateQuery("api1 = api2")); // -> true

I found something similar to your requirement
Not 100% sure but maybe this could help
You need your mapper to read the tree
Assuming you are using Jackson
You can have
ObjectMapper mapper=new ObjectMapper();
JsonNode object1=mapper.readTree(response1):
JsonNode object2=mapper.readTree(response2);
assertEquals(object1, object2);
Even though the order is not the same, it should give you true.
Click here for more

Removing fields from json string

I am writing api tests. I am using rest assured to make the requests the following way:
public void POSTNewRequest(String endpoint, String requestBody){
response = given().auth().none()
.header("Content-Type", "application/json")
.contentType(ContentType.JSON)
.when()
.body(requestBody).log().all()
.post(endpoint);
}
The requestBody I'm passing in the request is constructed by converting custom java objects to a string using ObjectMapper.writeValueAsString(requestBody).
This method has been working great for me, but now I need to make a bunch of requests where there is a certain field missing. eg:
{
"foo": [
{
"description": "dflt desc",
"ref": "abcd",
"FIELDTOREMOVE": 0,
"customArray": {
"number": 22,
"letter": "B"
}
}
],
"moreInfo": {
"email": "test#test.be",
"name": "Jhon Doe"
}
}
Now I would like to remove the field "FIELDTOREMOVE" inside this request just before the post method. I tried to convert the requestBody string to a JsonNode and then removing the field but it doesn't remove the field.
private void removeNullFields(String requestBody) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
JsonNode jsonNode = objectMapper.readTree(requestBody);
System.out.println(jsonNode.get("FIELDTOREMOVE"));
((ObjectNode)jsonNode).remove("FIELDTOREMOVE");
}
And when I try to print the value the field its returning "null" so I'm obviously doing something wrong...
I also tried achieving the same by using the gson library with similar results so I guess there is a misunderstanding on my end but can't figure out where to look to fix my problem.
In short: I'm making api requests using the rest assured library by passing a string as the body but in this string I sometimes have to remove certain fields the check what response I'm getting.

The "foo" in your JSON is an array. You should do:
ObjectMapper mapper = new ObjectMapper();
JsonNode jsonNode = mapper.readTree(requestBody);
jsonNode.get("foo").forEach(e -> ((ObjectNode) e).remove("FIELDTOREMOVE"));
System.out.println(jsonNode.toPrettyString());
Output:
{
"foo" : [ {
"description" : "dflt desc",
"ref" : "abcd",
"customArray" : {
"number" : 22,
"letter" : "B"
}
} ],
"moreInfo" : {
"email" : "test#test.be",
"name" : "Jhon Doe"
}
}

You can use this library:
<!-- https://mvnrepository.com/artifact/org.json/json -->
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20210307</version>
</dependency>
So that the code would look like:
import org.json.JSONObject;
public class JSONManipulation {
static final String JSON = "{\n" +
" \"foo\": [\n" +
" {\n" +
" \"description\": \"dflt desc\",\n" +
" \"ref\": \"abcd\", \n" +
" \"FIELDTOREMOVE\": 0,\n" +
" \"customArray\": {\n" +
" \"number\": 22,\n" +
" \"letter\": \"B\"\n" +
" }\n" +
" }\n" +
" ],\n" +
" \"moreInfo\": {\n" +
" \"email\": \"test#test.be\",\n" +
" \"name\": \"Jhon Doe\"\n" +
" }\n" +
"}";
public static void main(String[] args) {
JSONObject jsonObject = new JSONObject(JSON);
System.out.println("Value before edit: " + jsonObject.toString());
jsonObject.getJSONArray("foo").getJSONObject(0).remove("FIELDTOREMOVE");
System.out.println("Value after edit: " + jsonObject.toString());
}
}
The output would be:
Value before edit: {"foo":[{"FIELDTOREMOVE":0,"ref":"abcd","description":"dflt desc","customArray":{"number":22,"letter":"B"}}],"moreInfo":{"name":"Jhon Doe","email":"test#test.be"}}
Value after edit: {"foo":[{"ref":"abcd","description":"dflt desc","customArray":{"number":22,"letter":"B"}}],"moreInfo":{"name":"Jhon Doe","email":"test#test.be"}}
So you can manipulate with your JSON content and then post is as a String.

How to catch a string in JSON file in java?

I have a JSON file and need to get the parameter ' fulltext ' , but I'm new to JSON and do not know how to retrieve it in Java . Could someone explain to me how caught this value fulltext ?
Here a piece of the file in JSON.
{
"head": {
"vars": [ "author" , "title" , "paper" , "fulltext" ]
} ,
"results": {
"bindings": [
{
"author": { "type": "uri" , "value": "http://data.linkededucation.org/resource/lak/person/richard-scheines" } ,
"title": { "type": "literal" , "value": "Discovering Prerequisite Relationships among Knowledge Components" } ,
"paper": { "type": "uri" , "value": "http://data.linkededucation.org/resource/lak/conference/edm2014/paper/492" } ,
"fulltext": { "type": "literal" , "value": "GET TEXT" }
} ,

Json library download from here jar dowonload form here
Add this code in JSonParsing.java
import org.json.*;
public class JSonParsing {
public static void main(String[] args){
String source = "{\n" +
" \"head\": {\n" +
" \"vars\": [ \"author\" , \"title\" , \"paper\" , \"fulltext\" ]\n" +
" } ,\n" +
" \"results\": {\n" +
" \"bindings\": [\n" +
" {\n" +
" \"author\": { \"type\": \"uri\" , \"value\": \"http://data.linkededucation.org/resource/lak/person/richard-scheines\" } ,\n" +
" \"title\": { \"type\": \"literal\" , \"value\": \"Discovering Prerequisite Relationships among Knowledge Components\" } ,\n" +
" \"paper\": { \"type\": \"uri\" , \"value\": \"http://data.linkededucation.org/resource/lak/conference/edm2014/paper/492\" } ,\n" +
" \"fulltext\": { \"type\": \"literal\" , \"value\": \"GET TEXT\" }\n" +
" }\n" +
" ]\n" +
" }\n" +
"}\n" +
"";
JSONObject main = new JSONObject(source);
JSONObject results = main.getJSONObject("results");
JSONArray bindings = results.getJSONArray("bindings");
JSONObject firstObject = bindings.getJSONObject(0);
JSONObject fulltextOfFirstObject = firstObject.getJSONObject("fulltext");
String type = fulltextOfFirstObject.getString("type");
String value = fulltextOfFirstObject.getString("value");
System.out.println("Type :"+ type+"\nValue :"+value);
}
}
NOTE: In JSON {} represents jsonObject and [] represents jsonArray.

You can use org.json/Jackson to convert this string to JSONObject.
If it is a JSONObject called val;
then val.get("results").get("bindings").get(0).get("fulltext")
will give you the full text of first element of bindings.

There are many good JSON parsing libraries for Java. Try out Org.JSON (Maven) or Jackson Library (Maven) or my personal favorite Google's GSON Library (Maven) that can convert Java Objects into JSON and back.

I recommend you using https://github.com/alibaba/fastjson , It's easy to use.

Decoding url from json on Android

From a Rest API, I get json data in the following format:
[
{
"id": "1",
"item": "tea",
"price": "7.5",
"image": "http:\/\/192.168.1.3\/CI\/images\/tea.jpg",
"veg": "0",
"category": "drinks"
},
{
"id": "2",
"item": "coffee",
"price": "10",
"image": "http:\/\/192.168.1.3\/CI\/images\/coffee.jpg",
"veg": "0",
"category": "drinks"
}
]
From the API I get Json as a string and it contains backslashes in front of url's forward slashes, which is according to the json encoding specification. And I am correctly able to json_decode and get url from php. In android I store the json string in a variable named "menu_json".
Then I am trying to parse and get the image url from it using the following code:
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
try{
JSONObject menuApiObj = new JSONObject(menu_json);
JSONArray menuObj = menuApiObj.getJSONArray("menu");
for (int i = 0; i < menuObj.length(); i++){
JSONObject row = menuObj.getJSONObject(i);
rowString = row.getString("image");
imageUrl = row.toString();
Log.e("rowString", rowString);
Log.e("imageUrl", imageUrl);
}
The output I get is:
{
"id": "1",
"item": "tea",
"price": "7.5",
"image": "tea.jpg",
"veg": "0",
"category": "drinks"
}
The image field is supposed to be:
http://192.168.1.3/CI/images/tea.jpg
But instead I get just:
tea.jpg
When json_decode the API response in PHP, I get the correctly decoded url. But in Android, I am not getting the correctly decoded url in image field.
Please help!
Here is the complete API response:
{"menu":[{"id":"1","item":"tea","price":"7.5","image":"tea.jpg","veg":"0","category":"drinks"},{"id":"2","item":"cofee","price":"10","image":"coffee.jpg","veg":"0","category":"drinks"},{"id":"3","item":"crispy chicken","price":"160","image":"crispy-chicken.jpg","veg":"0","category":"curries"}],"cat_wise":[{"category":"drinks","items":[{"id":"1","item":"tea","price":"7.5","image":"http:\/\/192.168.1.3\/CI\/images\/tea.jpg","veg":"0","category":"drinks"},{"id":"2","item":"cofee","price":"10","image":"http:\/\/192.168.1.3\/CI\/images\/coffee.jpg","veg":"0","category":"drinks"}]},{"category":"curries","items":[{"id":"3","item":"crispy chicken","price":"160","image":"http:\/\/192.168.1.3\/CI\/images\/crispy-chicken.jpg","veg":"0","category":"curries"}]},{"category":"main","items":[]}]}

I'm not sure what Json library you're using, but it looks like org.json. I thought your code looked sane, so I implemented it and do not see the output that you are seeing. My guess is that your input data isn't what you expect it to be.
final JSONArray menuObj = new JSONArray("[\n" +
" {\n" +
" \"id\": \"1\",\n" +
" \"item\": \"tea\",\n" +
" \"price\": \"7.5\",\n" +
" \"image\": \"http://192.168.1.3/CI/images/tea.jpg\",\n" +
" \"veg\": \"0\",\n" +
" \"category\": \"drinks\"\n" +
" },\n" +
" {\n" +
" \"id\": \"2\",\n" +
" \"item\": \"coffee\",\n" +
" \"price\": \"10\",\n" +
" \"image\": \"http://192.168.1.3/CI/images/coffee.jpg\",\n" +
" \"veg\": \"0\",\n" +
" \"category\": \"drinks\"\n" +
" }\n" +
"]");
for (int i = 0; i < menuObj.length(); i++){
final JSONObject row = menuObj.getJSONObject(i);
System.out.println("imageUrl: " + row.getString("image"));
System.out.println("rowString: " + row);
}
Output:
imageUrl: http://192.168.1.3/CI/images/tea.jpg rowString:
{"image":"http://192.168.1.3/CI/images/tea.jpg","item":"tea","price":"7.5","veg":"0","id":"1","category":"drinks"}
imageUrl: http://192.168.1.3/CI/images/coffee.jpg rowString:
{"image":"http://192.168.1.3/CI/images/coffee.jpg","item":"coffee","price":"10","veg":"0","id":"2","category":"drinks"}

To parse JSON Array :
JSONArray jArray = jObject.getJSONArray("menu");
for (int i = 0; i < jArray.length(); i++) {
JSONObject innerjObject =jArray.getJSONObject(i);
String image =innerjObject.getString("image");
array_list.add(image);
}
output: http://192.168.1.3/CI/images/tea.jpg
And to display this image to imageview use library :
compile 'com.nostra13.universalimageloader:universal-image-loader:1.9.5'
using Loadimagview method of library load image in imageview