I've a problem trying to make my page printing out the JSONObject in the order i want. In my code, I entered this:
JSONObject myObject = new JSONObject();
myObject.put("userid", "User 1");
myObject.put("amount", "24.23");
myObject.put("success", "NO");
However, when I see the display on my page, it gives:
JSON formatted string: [{"success":"NO", "userid":"User 1", "bid":24.23}]
I need it in the order of userid, amount, then success. Already tried re-ordering in the code, but to no avail. I've also tried .append....need some help here thanks!!
You cannot and should not rely on the ordering of elements within a JSON object.
From the JSON specification at https://www.json.org/
An object is an unordered set of
name/value pairs
As a consequence,
JSON libraries are free to rearrange the order of the elements as they see fit.
This is not a bug.
I agree with the other answers. You cannot rely on the ordering of JSON elements.
However if we need to have an ordered JSON, one solution might be to prepare a LinkedHashMap object with elements and convert it to JSONObject.
#Test
def void testOrdered() {
Map obj = new LinkedHashMap()
obj.put("a", "foo1")
obj.put("b", new Integer(100))
obj.put("c", new Double(1000.21))
obj.put("d", new Boolean(true))
obj.put("e", "foo2")
obj.put("f", "foo3")
obj.put("g", "foo4")
obj.put("h", "foo5")
obj.put("x", null)
JSONObject json = (JSONObject) obj
logger.info("Ordered Json : %s", json.toString())
String expectedJsonString = """{"a":"foo1","b":100,"c":1000.21,"d":true,"e":"foo2","f":"foo3","g":"foo4","h":"foo5"}"""
assertEquals(expectedJsonString, json.toString())
JSONAssert.assertEquals(JSONSerializer.toJSON(expectedJsonString), json)
}
Normally the order is not preserved as below.
#Test
def void testUnordered() {
Map obj = new HashMap()
obj.put("a", "foo1")
obj.put("b", new Integer(100))
obj.put("c", new Double(1000.21))
obj.put("d", new Boolean(true))
obj.put("e", "foo2")
obj.put("f", "foo3")
obj.put("g", "foo4")
obj.put("h", "foo5")
obj.put("x", null)
JSONObject json = (JSONObject) obj
logger.info("Unordered Json : %s", json.toString(3, 3))
String unexpectedJsonString = """{"a":"foo1","b":100,"c":1000.21,"d":true,"e":"foo2","f":"foo3","g":"foo4","h":"foo5"}"""
// string representation of json objects are different
assertFalse(unexpectedJsonString.equals(json.toString()))
// json objects are equal
JSONAssert.assertEquals(JSONSerializer.toJSON(unexpectedJsonString), json)
}
You may check my post too: http://www.flyingtomoon.com/2011/04/preserving-order-in-json.html
u can retain the order, if u use JsonObject that belongs to com.google.gson :D
JsonObject responseObj = new JsonObject();
responseObj.addProperty("userid", "User 1");
responseObj.addProperty("amount", "24.23");
responseObj.addProperty("success", "NO");
Usage of this JsonObject doesn't even bother using Map<>
CHEERS!!!
Real answer can be found in specification, json is unordered.
However as a human reader I ordered my elements in order of importance. Not only is it a more logic way, it happened to be easier to read. Maybe the author of the specification never had to read JSON, I do.. So, Here comes a fix:
/**
* I got really tired of JSON rearranging added properties.
* Specification states:
* "An object is an unordered set of name/value pairs"
* StackOverflow states:
* As a consequence, JSON libraries are free to rearrange the order of the elements as they see fit.
* I state:
* My implementation will freely arrange added properties, IN SEQUENCE ORDER!
* Why did I do it? Cause of readability of created JSON document!
*/
private static class OrderedJSONObjectFactory {
private static Logger log = Logger.getLogger(OrderedJSONObjectFactory.class.getName());
private static boolean setupDone = false;
private static Field JSONObjectMapField = null;
private static void setupFieldAccessor() {
if( !setupDone ) {
setupDone = true;
try {
JSONObjectMapField = JSONObject.class.getDeclaredField("map");
JSONObjectMapField.setAccessible(true);
} catch (NoSuchFieldException ignored) {
log.warning("JSONObject implementation has changed, returning unmodified instance");
}
}
}
private static JSONObject create() {
setupFieldAccessor();
JSONObject result = new JSONObject();
try {
if (JSONObjectMapField != null) {
JSONObjectMapField.set(result, new LinkedHashMap<>());
}
}catch (IllegalAccessException ignored) {}
return result;
}
}
from lemiorhan example
i can solve with just change some line of lemiorhan's code
use:
JSONObject json = new JSONObject(obj);
instead of this:
JSONObject json = (JSONObject) obj
so in my test code is :
Map item_sub2 = new LinkedHashMap();
item_sub2.put("name", "flare");
item_sub2.put("val1", "val1");
item_sub2.put("val2", "val2");
item_sub2.put("size",102);
JSONArray itemarray2 = new JSONArray();
itemarray2.add(item_sub2);
itemarray2.add(item_sub2);//just for test
itemarray2.add(item_sub2);//just for test
Map item_sub1 = new LinkedHashMap();
item_sub1.put("name", "flare");
item_sub1.put("val1", "val1");
item_sub1.put("val2", "val2");
item_sub1.put("children",itemarray2);
JSONArray itemarray = new JSONArray();
itemarray.add(item_sub1);
itemarray.add(item_sub1);//just for test
itemarray.add(item_sub1);//just for test
Map item_root = new LinkedHashMap();
item_root.put("name", "flare");
item_root.put("children",itemarray);
JSONObject json = new JSONObject(item_root);
System.out.println(json.toJSONString());
JavaScript objects, and JSON, have no way to set the order for the keys. You might get it right in Java (I don't know how Java objects work, really) but if it's going to a web client or another consumer of the JSON, there is no guarantee as to the order of keys.
Download "json simple 1.1 jar" from this https://code.google.com/p/json-simple/downloads/detail?name=json_simple-1.1.jar&can=2&q=
And add the jar file to your lib folder
using JSONValue you can convert LinkedHashMap to json string
For those who're using maven, please try com.github.tsohr/json
<!-- https://mvnrepository.com/artifact/com.github.tsohr/json -->
<dependency>
<groupId>com.github.tsohr</groupId>
<artifactId>json</artifactId>
<version>0.0.1</version>
</dependency>
It's forked from JSON-java but switch its map implementation with LinkedHashMap which #lemiorhan noted above.
As all are telling you, JSON does not maintain "sequence" but array does, maybe this could convince you:
Ordered JSONObject
For Java code, Create a POJO class for your object instead of a JSONObject.
and use JSONEncapsulator for your POJO class.
that way order of elements depends on the order of getter setters in your POJO class.
for eg. POJO class will be like
Class myObj{
String userID;
String amount;
String success;
// getter setters in any order that you want
and where you need to send your json object in response
JSONContentEncapsulator<myObj> JSONObject = new JSONEncapsulator<myObj>("myObject");
JSONObject.setObject(myObj);
return Response.status(Status.OK).entity(JSONObject).build();
The response of this line will be
{myObject : {//attributes order same as getter setter order.}}
The main intention here is to send an ordered JSON object as response. We don't need javax.json.JsonObject to achieve that. We could create the ordered json as a string.
First create a LinkedHashMap with all key value pairs in required order. Then generate the json in string as shown below.
Its much easier with Java 8.
public Response getJSONResponse() {
Map<String, String> linkedHashMap = new LinkedHashMap<>();
linkedHashMap.put("A", "1");
linkedHashMap.put("B", "2");
linkedHashMap.put("C", "3");
String jsonStr = linkedHashMap.entrySet().stream()
.map(x -> "\"" + x.getKey() + "\":\"" + x.getValue() + "\"")
.collect(Collectors.joining(",", "{", "}"));
return Response.ok(jsonStr).build();
}
The response return by this function would be following:
{"A":"1","B":"2","C":"3"}
Underscore-java uses linkedhashmap to store key/value for json. I am the maintainer of the project.
Map<String, Object> myObject = new LinkedHashMap<>();
myObject.put("userid", "User 1");
myObject.put("amount", "24.23");
myObject.put("success", "NO");
System.out.println(U.toJson(myObject));
I found a "neat" reflection tweak on "the interwebs" that I like to share.
(origin: https://towardsdatascience.com/create-an-ordered-jsonobject-in-java-fb9629247d76)
It is about to change underlying collection in org.json.JSONObject to an un-ordering one (LinkedHashMap) by reflection API.
I tested succesfully:
import java.lang.reflect.Field;
import java.util.LinkedHashMap;
import org.json.JSONObject;
private static void makeJSONObjLinear(JSONObject jsonObject) {
try {
Field changeMap = jsonObject.getClass().getDeclaredField("map");
changeMap.setAccessible(true);
changeMap.set(jsonObject, new LinkedHashMap<>());
changeMap.setAccessible(false);
} catch (IllegalAccessException | NoSuchFieldException e) {
e.printStackTrace();
}
}
[...]
JSONObject requestBody = new JSONObject();
makeJSONObjLinear(requestBody);
requestBody.put("username", login);
requestBody.put("password", password);
[...]
// returned '{"username": "billy_778", "password": "********"}' == unordered
// instead of '{"password": "********", "username": "billy_778"}' == ordered (by key)
Just add the order with this tag
#JsonPropertyOrder({ "property1", "property2"})
Not sure if I am late to the party but I found this nice example that overrides the JSONObject constructor and makes sure that the JSON data are output in the same way as they are added. Behind the scenes JSONObject uses the MAP and MAP does not guarantee the order hence we need to override it to make sure we are receiving our JSON as per our order.
If you add this to your JSONObject then the resulting JSON would be in the same order as you have created it.
import java.io.IOException;
import java.lang.reflect.Field;
import java.util.LinkedHashMap;
import org.json.JSONObject;
import lombok.extern.java.Log;
#Log
public class JSONOrder {
public static void main(String[] args) throws IOException {
JSONObject jsontest = new JSONObject();
try {
Field changeMap = jsonEvent.getClass().getDeclaredField("map");
changeMap.setAccessible(true);
changeMap.set(jsonEvent, new LinkedHashMap<>());
changeMap.setAccessible(false);
} catch (IllegalAccessException | NoSuchFieldException e) {
log.info(e.getMessage());
}
jsontest.put("one", "I should be first");
jsonEvent.put("two", "I should be second");
jsonEvent.put("third", "I should be third");
System.out.println(jsonEvent);
}
}
Just use LinkedHashMap to keep de order and transform it to json with jackson
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.LinkedHashMap;
LinkedHashMap<String, Object> obj = new LinkedHashMap<String, Object>();
stats.put("aaa", "aaa");
stats.put("bbb", "bbb");
stats.put("ccc", "ccc");
ObjectMapper mapper = new ObjectMapper();
String json = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(obj);
System.out.println(json);
maven dependency
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.9.10.7</version>
</dependency>
I just want the order for android unit tests that are somehow randomly changing overtime with this cool org.json.JSONObject, even thou it looks like it uses linked map but probably depends on api you compile it with or something, so it has different impl. with different android api probably.
I would suggest something like this:
object Json {
#SuppressLint("DiscouragedPrivateApi")
fun Object() = org.json.JSONObject().apply {
runCatching {
val nameValuePairs: Field = javaClass.getDeclaredField("nameValuePairs")
nameValuePairs.isAccessible = true
nameValuePairs.set(this, LinkedHashMap<String, Any?>())
}.onFailure { it.printStackTrace() }
}
}
Usage:
val jsonObject = Json.Object()
...
This is just some possibility I use it little differently so I modified it to post here. Sure gson or other lib is another option.
Suggestions that specification is bla bla are so shortsighted here, why you guys even post it, who cares about 15 years old json spec, everyone wants it ordered anyway.
Iterator searchGetResponseIterator = searchGetResponse.entrySet().iterator();
Object obj = null;
Object dataPicker = null;
while(searchGetResponseIterator.hasNext()) {
Map.Entry searchGetResponseElement = (Map.Entry)searchGetResponseIterator.next();
if(searchGetResponseElement.getKey().equals("seSearch")) {
obj = searchGetResponseElement.getValue();
}
}
want to store the "obj" in map. In obj i have this >>
{"columns":[{"exp":{"$ali":"t2acName"},"ali":"sourceacName"},"**id**":"4c99eedc836adbeefd0e10db76a","**table**":"public.4c99eedc836adbeefd0e10db76a","fieldIds":["0336e7c7-b236-41b7-8ae8-194dcfc49693","369bc4de-b220-41a2-a7be-090c6386aa2e","37926ca2-044f-44f2-a349-0f2e1b61f120","2310dcca-010f-4830-b300-01fb00d2d15e","306554be-92b3-41a3-bb24-b59f4adc8b79","21cdee98-e3b4-4da9-a502-587c0a221413","1f26c177-944f-4378-9e26-8ee0882221cc","13532fa7-8320-4cc1-90fb-aa8fcc3f5f6f","16d3a857-e8d5-4172-87f5-a149187ec409",],"executionQueue":[{"flow":0,"start":1574674632999,"count":0,"rEnd":1574676432999,"status":"done"},{"flow":0,"start":1574620200000,"count":0,"rEnd":1574674632999,"status":"done"}]}
and i want to get id and table from table again.
You know the format of obj
{"**id**":"4c99eedc836adbeefd0e10db76a","**table**":"public.
Looks like there is consistent pattern where id appears, and where table appears in that blob of string / json.
Look at RegEx java tutorial and create one to extract id and table
https://www.baeldung.com/regular-expressions-java
An easier way is to convert the Object string to a map and get your fields.
if(searchGetResponseElement.getKey().equals("seSearch")) {
obj = searchGetResponseElement.getValue();
ObjectMapper objectMapper = new ObjectMapper();
HashMap responseMap = objectMapper.readValue(obj.toString(), HashMap.class);
}
Once you have the responseMap, you can inspect that object and get the required hierarchy from it.
For example: ((Map) ((List) responseMap.get("columns")).get(0)).get("id")
Note: The above example may not accurately represent your response model.
We have a requirement to update the JSON data in middle and need to return the updated JSON data using java. Also it should support any type of JSON data.
ex:
Assume {object:{"color":"red","shape":"Triangle"}} is the JSON data and in this we need to update the shape value to Rectangle and we need to return the updated JSON data as below:
{object:{"color":"red","shape":"Rectangle"}}
For this we need to pass the element path ( which element we need to update) and updateText and JSON Data to the JAVA code.
here is the methodCall:
updateValue("object/shape", "Rectangle", "{object:{"color":"red","shape":"Triangle"}}")
We tried below code using Gson library. But with this code we are able to update the targeted Json element, but the requirement is to return the entire JSON data with the updated value.
So please suggest how do we re-build the JSON data with the updated text.
Below is the code we tried to update the Json Data.
public String updateValue(String keyPath, String updateText, String jsonText) {
String[] keys = keyPath.split("/");
JsonParser jsonParser = new JsonParser();
JsonObject jsonObject = (JsonObject) jsonParser.parse(jsonText);
String result = "";
for(String key : keys)
{
if (jsonObject.get(key) instanceof JsonObject)
{
jsonObject = (JsonObject)jsonObject.get(key);
}
else if(jsonObject.get(key) instanceof JsonArray)
{
JsonArray jsonArray = (JsonArray)jsonObject.get(key);
result = jsonArray.toString();
}
else
{
result = jsonObject.get(key).toString();
}
}
result = result.replace(result, updateText);
return result;
}
The problem lies in the way you do the replacements. When you translate the JsonObject to String, you lose the object, and after replacement, you just have the replaced String. To fix it, you need to operate directly on the object, instead of the String counterpart. Because JsonObject is mutable, holding a reference to the input will reflect the changes. One drawback is you can't replace a value in a JsonArray this way, partly because you don't know which element to replace. To accomplish that, you will need a little more in the input(either the value to replace or the element position).
public String updateValue(String keyPath, String updateText, String jsonText) {
String[] keys = keyPath.split("/");
JsonParser jsonParser = new JsonParser();
JsonObject jsonObject = (JsonObject) jsonParser.parse(jsonText);
JsonObject returnVal = jsonObject; // This holds the ref to target json object
JsonPrimitive jp = new JsonPrimitive(updateText);
String finalKey = keys[keys.length - 1];
for(String key : keys)
{
if (jsonObject.get(key).isJsonObject())
{
jsonObject = (JsonObject)jsonObject.get(key);
}
}
jsonObject.remove(finalKey);
jsonObject.add(finalKey, jp);
return returnVal.toString();
}
You can use JsonPath lib for that and try using the following code.
private static final Configuration configuration = Configuration.builder()
.jsonProvider(new JacksonJsonNodeJsonProvider())
.mappingProvider(new JacksonMappingProvider())
.build();
JsonNode updatedJson = JsonPath.using(configuration).parse(originaljson)
.set("use the path to go for value", "new value").json();
json = updatedJson.toString();
I have a little problem with stringify.
I am passing variable from Java to JavaScript.
In Java after out.println(strin); it looks like this:
[{"date":"01-18-2015"},{"date":"01-19-2015"},{"date":"01-21-2015"},{"date":"01-19-2015"},{"date":"01-19-2015"},{"date":"01-19-2015"}]
So I am trying to pass it to JavaScript
var obj = new String(<%= strin %>);
var tekst = JSON.stringify(obj);
alert(tekst);
But this alert still gives me [object Objetc],[object Object] etc.
However if I am putting that dates straightly to JS variable like this:
var zmienna = '[{"date":"01-18-2015"},{"date":"01-19-2015"},{"date":"01-21-2015"},{"date":"01-19-2015"},{"date":"01-19-2015"},{"date":"01-19-2015"}]';
stringify works good.
Im really confused about this. Can anyone give me some tips?
My code for json in Java looks like this:
String next_date = "";
JSONArray json = new JSONArray();
while (daty.next()) {
next_date = formatter.format(daty.getDate("date"));
JSONObject obj = new JSONObject();
obj.put("date", next_date);
json.put(obj);
}
String strin = json.toString();
It is the JSON notation (JavaScript Object Notation) that you taking advantage of.
When you declare a variable this way:
var zmienna = '[{"date":"01-18-2015"},{"date":"01-19-2015"},..];
you basically declare an array[] with elements that are objects{}.
It is equivalent to below code.
var firstDate = new Date("01-18-2015");
var secondDate =new Date("01-19-2015");
var zmienna = [firstDate, secondDate];
This is ready to use array, while in the other code you declare a String variable with some characters in it.
var obj = new String(<%= string %>);
I hope it clarified you understanding.
In the client side, I have constructed a JSOnARRAY like this:
{"filterEntries":[{"dataName":"mainContact","filterValue":"BILLGATES"}]}.
On the server side (java), I can retireve the values using :
jfilter = JSONValue.parse(jsonFilterStr); //jsonFilterStr={"filterEntries":[{"dataName":"mainContact","filterValue":"BILLGATES"}]}.
JSONArray jFilterEntries = (JSONArray) jfilter.get("filterEntries");
for (int i=0;i<jFilterEntries.size();i++){
JSONObject jFilterEntry = (JSONObject) jFilterEntries.get(i);
String dataName = (String) jFilterEntry.get("dataName");
String filterValue = (String) jFilterEntry.get("filterValue");
}
But the existing app is using flex.json.deserializer and I am unable to achieve the same using flex.json.deserializer. How should I proceed?
I wish to do something like this:
JSONDeserializer jsonDeserializer = new JSONDeserializer();
jsonDeserializer.use(null, List.class);
List<Map<String,String>> lMap= (List<Map<String,String>>)jsonDeserializer.deserialize(params);
Remember the top object that wraps the array. You have to handle that as well. You have to tell it to expect a Map inside the List. To do that you have to specify the type contained in the list by using the path expression "values".
Map<String,List<Map<String,String>>> result = new JSONDeserializer<Map<String,List<Map<String,String>>>>()
.use("values",List.class)
.use("values.values", Map.class)
.deserialize( json);
List<Map<String,String>> filterEntries = result.get("filterEntries");
Updated: Add the new keyword, and made the generic types on the right match the left.