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Inserting String variable into JSON which is in a form of String

I have a JSON payload saved as a String
String jsonBody = “{\n”
+ ” \“example\“: {\n”
+ ” \“example\“: [\n”
+ ” {\n”
+ ” \“example\“: 100,\n”
+ ” \“this_is_example_json_key\“: \“this_is_example_json_value\“,\n”
I created that by copying body from i.e Postman into
String jsonBody = "here I pasted the body";
Unfortunately I cannot have everything hardcoded there, so I have to change some values to variables. The JSON in postman looks like:
"this_is_example_json_key":"x"
And so on. Let's assume that:
String x = “this_is_example_json_value“;
If I just replace it like
+ ” \“this_is_example_json_key\“: \“ + x + \“,\n”
or something like that, the value in the body will be just this_is_example_json_value, where I need "this_is_example_json_value" (the "" marks are part of the value).
So the question is, how to set up those + / " in the String, so in the end in the value of the JSON I will end up with the value inside " ".
I've tried to play with the " / + but nothing of those were working. Variable must be passed with those " " because otherwise, the API is sending back an error.

Since java 15, if you want only use the string, you can also do in this way:
int this_is_example_json_value= 100;
String json = """
{
"this_is_example_json_key": %d
}
""".formatted(this_is_example_json_value);
Here the official jep.

Don't try to build up JSON using strings. Use a proper JSON parser.
import org.json.JSONException;
import org.json.JSONObject;
public class Eg {
public static void main(String[] args) throws JSONException {
String x = "this_is_example_json_value";
JSONObject example = new JSONObject();
example.put("this_is_example_json_key", x);
System.out.println(example.toString());
}
}
Which outputs:
{"this_is_example_json_key":"this_is_example_json_value"}
With no messing around wondering what needs to be escaped.

you can use an extra " \ " "
String x = "this_is_example_json_value";
String jsonBody = "{\n"
+ "\"example\": {\n"
+ " \"example\": [\n"
+ " {\n"
+ " \"example\": 100,\n"
+ "\"this_is_example_json_key\":" + "\"" + x + "\"" + "\n }"
+"\n ]\n }\n }";
in this case you will get a json string
{
"example": {
"example": [
{
"example": 100,
"this_is_example_json_key": "this_is_example_json_value"
}
]
}
}

Using JSONAssert to check if an item exists in a JSON array

I have a JSONObject that is similar to something like this:
{
"category":"abc"
"staus":""open"
"external":[
{"name":"123", "type":"OTHER"},
{"name":"678", "type":"ALPHA"},
{"name":"890", "type":"DELTA"}
]
}
If I want to use JSONAssert to check if the item {"name":"678"} exists and I don't know the item's order and the number of items in the "external" array, how should I do in Java?
It seems the ArrayValueMatcher should be the way to go but I just cannot get it works.
Please help

You could use JsonPath for this usecase :
JSONArray array = JsonPath.read(json, "$.external[?(#.name == '678')]");
Assertions.assertThat(array).hasSize(1);

Here is a complete example using JsonAssert:
#Test
public void foo() throws Exception {
String jsonString = "{\n" +
" \"category\":\"abc\",\n" +
" \"staus\":\"open\",\n" +
" \"external\":[\n" +
" {\"name\":\"123\", \"type\":\"OTHER\"},\n" +
" {\"name\":\"678\", \"type\":\"ALPHA\"},\n" +
" {\"name\":\"890\", \"type\":\"DELTA\"}\n" +
" ]\n" +
"}";
JsonAssert.with(jsonString).assertThat("$.external[*].name", hasItem(equalTo("678")));
}

Parsing Merriam Webster JSON data attributes wrapped in a double array?

I am attempting to get the definition of a word using the documentation from Merriam Webster's API - https://dictionaryapi.com/products/json#sec-2.def
The documentation shows the structure of the JSON response from the server, and I have been able to successfully parse the raw data into a just an array containing the "sense" object.
Screenshot of code and parsed data
My issue is being able to access the "sense" JSONObject, since I am currently in an array, I can't access the sense object. I have tried adding .getJSONArray(0) and .getJSONObject(0) after my code and both of those solutions did not work.
How can I continue parsing this JSON I currently have to the "dt" string?
JSONArray merriamResults = data.getJSONArray("Merriam")
.getJSONObject(0)
.getJSONArray("def")
.getJSONObject(0)
.getJSONArray("sseq")
.getJSONArray(0)
.getJSONArray(0);

Here.
String json = "{\"def\":[\n" +
" {\n" +
" \"sseq\":[\n" +
" [\n" +
" [\n" +
" \"sense\",\n" +
" {\n" +
" \"dt\":[[\"text\",\"{bc}a {a_link|backward} somersault especially\n" +
" in the air\"]]\n" +
" }\n" +
" ]\n" +
" ]\n" +
" ]\n" +
" }\n" +
"]}";
try {
JSONObject jsonObject = new JSONObject(json);
String dt = jsonObject.getJSONArray("def")
.getJSONObject(0)
.getJSONArray("sseq")
.getJSONArray(0)
.getJSONArray(0)
.getJSONObject(1)
.getJSONArray("dt")
.getJSONArray(0)
.getString(1);
Log.i("jsondata", dt);
} catch (JSONException e) {
e.printStackTrace();
}
my log:
12-02 21:38:12.316 14174-14174/com.example.pemba.sample I/jsondata: {bc}a {a_link|backward} somersault especially
in the air

How to parse custom objects from a list within a jsonstring?

I got the following json:
{
"ID": "1234567",
"dangereousCargo": true,
"numberOfPassangers": 164,
"cargo": [
{
"type": "Oil",
"amount": 8556
},
{
"type": "Chemicals",
"amount": 5593
}
]
}
From this question, I understood that it is possible to get the cargoList out of the jsonObject (if that list contains a certain type of object). But how do I get the seperate cargoObjects out of that list?
+Do the variable names of the jsonstring have to correspond with the variable names in my CargoClass? What if the jsonObject only contains type and amount and my CargoClass has more attributes?

You can iterate throws the JSONArray which represents your cargo list doing (not tested)
JSONObject json = new JSONObject(jsonString);
JSONArray cargoList = json.getJSONArray("cargo");
for(int i=0; i< cargoList.length(); i++) {
JSONObject cargo = cargoList.getJSONObject(i);
//Do something with cargo
}

But how do I get the seperate cargoObjects out of that list?
String jsonString = "{ ... }";
JSONObject json = new JSONObject(jsonString);
JSONArray cargoList = json.getJSONArray("cargo");
for(JSONObject cargo : cargoList)
{
//do something with your cargo element
}
Do the variable names of the jsonstring have to correspond with the
variable names in my CargoClass?
If you use the the get method from the JSONObject, you have to specify the exact name of the attribute in your jsonString. Following the example above:
String cargoType = cargo.getString("type");
By the way, if you want to use your already defined CargoClass, you need a Deserializer and all the attributes on your JSON must be the all present and all the same on your CargoClass: I suggest you to take a look at other SOs questions like this one.
What if the jsonObject only contains type and amount and my CargoClass
has more attributes?
The other attributes will be initialize in base of your class declaration

Using JSON Simple it is very easy to parse and read your data from your JSON. As other users have said there are a plethora of libraries out there that can accomplish this. Below is a tested example of your code.
public static void main(String[] args) throws JSONException {
String json = "{\n"
+ " ID: 1234567,\n"
+ " dangereousCargo: true,\n"
+ " numberOfPassangers: 164,\n"
+ " cargo: [\n"
+ " {\n"
+ " type: Oil,\n"
+ " amount: 8556\n"
+ " },\n"
+ " {\n"
+ " type: Chemicals,\n"
+ " amount: 5593\n"
+ " }\n"
+ " ]\n"
+ "}";
JSONObject data = new JSONObject(json);
int id = data.getInt("ID");
boolean danger = data.getBoolean("dangereousCargo");
int numOfPassengers = data.getInt("numberOfPassangers");
System.out.println("Current ID: " + id + "\n"
+ "Is Dangerous: " + danger + "\n"
+ "Number of Passengers: " + numOfPassengers + "\n");
JSONArray cargo = data.getJSONArray("cargo");
NumberFormat currency = NumberFormat.getCurrencyInstance();
for (int i = 0; i < cargo.length(); i++) {
JSONObject cargoObject = cargo.getJSONObject(i);
String type = cargoObject.getString("type");
double amount = cargoObject.getDouble("amount");
System.out.println("Current Type: " + type);
System.out.println("Current Amount: " + currency.format(amount));
}
}
}
The above code gives us the following output:
Once you have your data you can really do whatever you want with it.
Libraries
JSONSimple-https://code.google.com/p/json-simple/
GSON-https://github.com/google/gson

URL in JSON object as POST request Android

Please help me to send a JSON object in POST HTTP request through HttpClient, in Android.
The problem I am facing is that the JSON object having the URL is replaced by forward slash ,i.e
originally it should have the following value in JSON object
{"product":
{"featured_src":"https:\/\/example.com\/wp-content\/uploads\/2015\/06\/sidney-compressed.jpg,
"short_description":"this is a test","title":"Raiders from the North"}
}
i tried many options to keep it in the above format. But it always comes as {"featured_src":

We assume this is your input
private final static String JSON_DATA = "{"
+ " \"product\": ["
+ " {"
+ " \"featured_src\": \"https:\\/\\/example.com\\/wp-content"
+ "\\/uploads\\/2015\\/06\\/sidney-compressed.jpg\","
+ " \"short_description\": \"this is a test\","
+ " \"title\" : \"Raiders from the North\""
+ " }"
+ " ]"
+ "}";
You could use replace to do the trick.
YOUR_STRING.replace("\\", "");
Finally your method would look like this, by passing your string as parameter
private static String jsonUrlCorrector(String json_data) {
json_data = json_data.replace("\\", "");
return json_data;
}
Here is the input:
{"product":[{"featured_src":"https:\/\/example.com\/wp-content\/uploads\/2015\/06\/sidney-compressed.jpg","short_description": "this is a test","title":"Raiders from the North"}]}
Here is the output
{"product":[{"featured_src":"https://example.com/wp-content/uploads/2015/06/sidney-compressed.jpg","short_description":"this is a test","title":"Raiders from the North"}]}