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get a key value pair from a String json (simple object)

Im trying to get a key:value pair from a simple jsonString to add it after into a memory tab. If facing an issue cause my input is a string. and it looks like my loop isnot able to read the key value pair.
I read many topics about it, and im still in trouble with it. As you can see below
{"nom":"BRUN","prenom":"Albert","date_naiss":"10-10-1960","adr_email":"abrun#gmail.com","titre":"Mr","sexe":"F"}
and my method, find only on object... the result is the same in my loop
public static ArrayHandler jsonSimpleObjectToTab(String data) throws ParseException {
if( data instanceof String) {
final var jsonParser = new JSONParser();
final var object = jsonParser.parse(data);
final var array = new JSONArray();
array.put(object);
final var handler = new ArrayHandler("BW_funct_Struct");
for( KeyValuePair element : array) {
handler.addCell(element);
Log.warn(handler);
}
return handler;
} else {
throw new IllegalArgumentException("jsonSimpleObjectToTab: do not support complex object" + data + "to Tab");
}
}
i also tryed before to type my array as a List, Object etc, without the keyValuePair object, i would appreciate some help.
Thanks again dear StackOverFlowers ;)

You can try this :
const json = '{"nom":"BRUN","prenom":"Albert","date_naiss":"10-10-1960","adr_email":"abrun#gmail.com","titre":"Mr","sexe":"F"}';
map = new Map();
const obj = JSON.parse(json,(key,value) => {
map.set(key,value)
});
and you'll have every pair stored in map

Simply split the whole line at the commas and then split the resulting parts at the colon. This should give you the individual parts for your names and values.
Try:
supposing
String input = "\"nom\":\"BRUN\",\"prenom\":\"Albert\"";
then
String[] nameValuePairs = input.split(",");
for(String pair : nameValuePairs)
{
String[] nameValue = pair.split(":");
String name = nameValue[0]; // use it as you need it ...
String value = nameValue[1]; // use it as you need it ...
}

You can use TypeReference to convert to Map<String,String> so that you have key value pair.
String json = "{\"nom\":\"BRUN\",\"prenom\":\"Albert\",\"date_naiss\":\"10-10-1960\",\"adr_email\":\"abrun#gmail.com\",\"titre\":\"Mr\",\"sexe\":\"F\"}";
ObjectMapper objectMapper = new ObjectMapper();
TypeReference<Map<String,String>> typeReference = new TypeReference<Map<String, String>>() {
};
Map<String,String> map = objectMapper.readValue(json, typeReference);

I just answered a very similar question. The gist of it is that you need to parse your Json String into some Object. In your case you can parse it to Map. Here is the link to the question with my answer. But here is a short version: you can use any Json library but the recommended ones would be Jackson Json (also known as faster XML) or Gson(by Google) Here is their user guide site. To parse your Json text to a class instance you can use ObjectMapper class which is part of Jackson-Json library. For example
public <T> T readValue(String content,
TypeReference valueTypeRef)
throws IOException,
JsonParseException,
JsonMappingException
See Javadoc. But also I may suggest a very simple JsonUtils class which is a thin wrapper over ObjectMapper class. Your code could be as simple as this:
Map<String, Object> map;
try {
map = JsonUtils.readObjectFromJsonString(input , Map.class);
} catch(IOException ioe) {
....
}
Here is a Javadoc for JsonUtils class. This class is a part of MgntUtils open source library written and maintained by me. You can get it as Maven artifacts or from the Github

Unable to retrieve data from POST request

I am working in JAVA 1.8 to write and using Apache Tomcat to run the server, I am unable to retrieve data from a POST request i.e in JSON.
I actually need it in an HashMap and I can even parse and convert it into HashMap even if it is readable in JSON. I have tried several links on the internet and I always get exception like Could not deserialize to type interface PACKAGE NAME.
#POST
#Produces("application/json")
#Consumes("application/json")
#Path("ClassifyCase")
public Rules Classify(HttpServletRequest request) {
StringBuffer jb = new StringBuffer();
String line = null;
try {
BufferedReader reader = request.getReader();
while ((line = reader.readLine()) != null)
jb.append(line);
} catch (Exception e) { System.out.println("Buffer Reader Error"); }
System.out.println("What I read: "+jb);
System.out.println("Here la la l ala ");
// System.out.println("Case: ++ "+Case.toString());
System.out.println("Here la la l ala ");
Rules foundRule = new Rules();
// List<Rules> objListRules = new ArrayList<Rules>();
try
{
DataAccessInterface objDAInterface = new RuleDataAdapter();
AbstractDataBridge objADBridge = new DatabaseStorage(objDAInterface);
// foundRule = objADBridge.Classify(Case);
logger.info("Classification done!");
}
catch(Exception ex)
{
logger.info("Error in classification");
System.out.println("Couldnt Classify Properly!");
// return
}
return foundRule;
}
Can someone please share a guide on how can I receive this data and convert it into a Map or either I can directly get a Map!

I strongly recommend you to use this library of JSON..
You can find it in Maven Repository and it's so easy to parse a JSON to a Map or to a JSONArray or JSONObject... depends of your necessity what you want to do..
Here is a example show how to parse a JSON to a HashMap
Map<String, Object> map = new JSONObject(--JSONString here--).toMap();
And that's all...
Now, if your JSON has a list of objects, i mean like a list of maps, what you just need to do is this...
JSONArray jsonArray = new JSONArray(--JSON string here--);
for(int i = 0; i < jsonArray.length(); i++){
Map<String, Object> map = jsonArray.getJSONObject(i).toMap();
}
Here is the explanation.
You take you JSON string and pass it as a parameter to the JSONArray,what JSONArray does is, take your json string a parse it to like a list
Then you make a for to get each Object of that list and parse it to a map.
Note: what the JSONObject does, is take the object of the JSONArray and parse it... you can parse it to a map or you can get each object of that map..

String jsonString = "{\n" +
"\t\"1\": \"1\",\n" +
"\t\"FPG\": \"50\",\n" +
"\t\"Symptoms\": \"Yes\"\n" +
"}";
Map<String, String> map = new Gson().fromJson(jsonString, Map.class);
for (String key: map.keySet()) {
System.out.println(map.get(key));
}

The request you send does not contain proper JSON in the body. You are missing the commas ",". It should be something like this:
{
"1":"1",
"FPG":"50",
"Symptoms":"yes"
}
Just change it and give proper JSON format to the message.
Even if the request was not in your control, I would strongly suggest that you contacted the service that creates the message and asked from them to fix it.
It would be the last resort for me to make my own deserializer to handle an "inproper" message.
An easy way to check if your JSON is properly formated is an online formatter, e.g. https://jsonformatter.org/

Getting simple Json string from url and converting it to String[] Android

I am trying to pull Json string from url and put it into String[] inside my android application.
String i am getting from my url is "[\"What is your name?\",\"How do you do?\"]"
I am trying to create Quizz class in my app where i want to call constructor and then it pull data from url and put it into private variables.
I have tried many things but getting multiple errors (with network and other stuff) and now i am somewhere with async tasks where i got lost and think i am going totally wrong way.
Class i want to have is like this:
public class Quizz {
private String[] Questions;
public Quizz() {
// Here i want to load data from url into variable Questions
}
public String getQuestion(int id) {
return "Not implemented!";
}
}
And when i create Quizz object in my main activity i want to have questions loaded.

you can use the following article to help you decode your json
Article Link
Also, You can use JSONArray in the Following Article

Use Retrofit to Connect to API, and Use its converter to deserialize the JSON Response.
https://www.journaldev.com/13639/retrofit-android-example-tutorial
it's very effective and has error handling built into it.

I know you are looking for a string[] array but in this case its best to use a arraylist as sizes can change when retrieving the response.
//create empty strings arraylist
List<String> strings = new Arraylist<>()
//try parse the response as a JSONarray object
try{
//get url string response as a json array
JSONArray jsonArray = (JSONArray) urlStringResponse;
//parse through json array and add to list
for(int i = 0; i < jsonArray.length(); i++){
String str = (String) jsonArray.getJSONObject(i);
strings.add(str);
}
} catch (JSONException e) {
Log.e("JSON", "Problem parsing the JSON results", e);
}

What about to use String.split() method?
val string = "[\"What is your name?\",\"How do you do?\"]"
val split: List<String> = string.subSequence(1, string.length - 1).split(',')
val array = split.toTypedArray()
array.forEach { println(it) }
And result will be
"What is your name?"
"How do you do?"

Find JSON object in JSON array

I have a goal to verify that certain JSON that I've got from RabbitMQ corresponds to one of expected JSONs in an array in a single file.
In other words, I need to verify that this JSON:
{
"networkCode":"network",
"programId":"92000"
}
is present in this JSON array:
[
{
"networkCode":"network",
"programId":"92000"
},
{
"networkCode":"network",
"programId":"92666"
}
]
Thank you very much for help!
Some part of my code
//GET DESIRABLE JSON
String message = new String(delivery.getBody(), StandardCharsets.UTF_8);
JSONObject myJSON= new JSONObject(message);
//GET THE JSON ARRAYS FROM FILE
JSONParser parser = new JSONParser();
Object expectedJSONs= parser.parse(new FileReader("C:\\amqpclient\\src\\test\\java\\tradeDoubler\\ExpectedDTO.json"));
JSONArray expectedArray = (JSONArray) expectedJSONs;
JSONAssert.assertEquals(
myJSON, expectedArray , JSONCompareMode.LENIENT);
Compilation says that cannot resolve this
Exception in thread "main" java.lang.AssertionError: Expecting a JSON array, but passing in a JSON object

Org.json library is quite easy to use.
Example code below:
import org.json.*;
JSONObject obj = new JSONObject(" yourJSONObjectHere ");
JSONArray arr = obj.getJSONArray("networkArray");
for (int i = 0; i < arr.length(); i++)
{
String networkCode = arr.getJSONObject(i).getString("networkCode");
......
}
By iterating on your JSONArray, you can check if each object is equal to your search.
You may find more examples from: Parse JSON in Java

May I suggest you to use the Gson Library?
You can use something like this. But It will throw an exception if the json doesn't match/contains the fields.
Type listType = new TypeToken<ArrayList<YourJavaClassJsonModel>>() {
}.getType();
List<YourJavaClassJsonModel> resultList = gson.fromJson(JsonString, listType);
Hope it may help

You could use a JSON parser to convert the JSON to a Java object (Jackson and GSON are good options), and then check that object.

Filter JSON for keys & values using other JSON objects

I'm currently having the following issue:
I wish to loop through a set of JSON files. I want to filter out certain JSON files that match a filter. This filter is another JSON object.
MongoDB is able to do this; you give a JSON object as parameter and it will list documents containing the given JSON elements.
I need a flatfile version of this, but I am not able to succeed. I'm using GSON as my JSON library.

Consumes an array of file paths that each contain a JSON string, and a JsonObject that represents the filter rules. Returns a list of file paths that match the filter rules.
public List<String> filter(String[] filePaths, JsonObject rules) throws FileNotFoundException {
final List<String> filtered = new ArrayList<String>();
final Set<Map.Entry<String, JsonElement>> rulesEntries = rules.entrySet();
for (String path : filePaths) {
final Reader reader = new BufferedReader(new InputStreamReader(new FileInputStream(new File(path))));
final JsonObject file = jsonParser.parse(reader).getAsJsonObject();
final Set<Map.Entry<String, JsonElement>> fileEntries = file.entrySet();
if (fileEntries.containsAll(rulesEntries)) filtered.add(path);
}
return filtered;
}