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Pretty print for JSON in Java works fine for the console, but in browser it does not work

I have a JSON file and I want to retrieve its content from a API call within a rest controller created in Java Spring Boot.
I get the content of the .json file into a String and use the below method ( one of them ) in order to pretty print.
If I system.out.println() the output, it gets pretty printed, but in the browser it is displayed roughly and with no indentation. I had more approaches :
String content = new String(Files.readAllBytes(resource.toPath()));
Gson gson = new GsonBuilder().setPrettyPrinting().create();
JsonParser jp = new JsonParser();
JsonElement je = jp.parse(content);
String prettyJsonString = gson.toJson(je);
System.out.println(prettyJsonString);
return prettyJsonString;
The other approach returns the same ugly output in browser, but it also adds "/r/n":
ObjectMapper mapper = new ObjectMapper();
mapper.enable(SerializationFeature.INDENT_OUTPUT);
String prettyJsonString = mapper.writeValueAsString(content);
return prettyJsonString;
Can anyone help me get the pretty output in browser as well?

Formatting String for console output and for HTML output are two VERY different tasks. Method setPrettyPrinting() is for console printing. HTML browser will ignore "\n" symbols and will not respect multiple spaces replacing them with a single space etc. In general, it is usually a client-side task to format the output. But I delt once with this problem and wrote a method that takes a console-formatted string and converts it to Html formatted String. For instance, it replaces all "\n" symbols with br Html tags. It does some other things as well. I had some success with it, but sometimes some unexpected problems occurred. You are welcome to use it. The method is available in MgntUtils Open source library. Here is its JavaDoc. The library itself is available as Maven artifact here and on Github (including source code and JavaDoc) here. An article about the library is here. Your code would look like this:
String htmlString = TextUtils.formatStringToPreserveIndentationForHtml(jsonPrettyString);

I had this same problem and stumbled upon how to get it to pretty print in the browser.
In your application.properties file, add these two lines:
# Preferred JSON mapper to use for HTTP message conversion.
spring.mvc.converters.preferred-json-mapper=gson
# Whether to output serialized JSON that fits in a page for pretty printing.
spring.gson.pretty-printing=true
Reference: https://www.callicoder.com/configuring-spring-boot-to-use-gson-instead-of-jackson/
Maybe related: https://stackoverflow.com/a/62044963

How to create new text file on the fly if one file overflow in java

I am writing json data into one file. It works fine for small data but for large data it is writing some amount of data and remaining data gets skipped. So Please guide me how to create new file if one gets fulled in java?
Currently i am using below code to write json object into a file.
Below is the sample which is quite similar to my working code.
String json=null;
for(int counter=0;counter<2;counter++){
JSONObject obj=new JSONObject();
JSONObject second=new JSONObject();
obj.put("ClassName", "sample.com");
obj.put("Query", "query");
obj.put("Message", "Successfylly");
second.put("Number"+sequence++, obj);
company.add(second);
//file.write(obj.toJSONString());
Gson gson = new GsonBuilder().setPrettyPrinting().create();
json = gson.toJson(company);
file.write(json);
file.close();
}
Please guide me how to create new file if existing file gets fulled while writing json object into a text file.

It's difficult to tell, as your code is not formatted well, but it looks like every iteration of your loop is overwriting the variable json. Only the value of json at the last iteration of the loop will be written to the file.
Move the call to file.write(json) inside the loop.

Adding elements to an JSON object in a external JSON file?

(After months of surfing the internet, talking to the school's computing department and try code out, I still don't get how to do it, but I do know more specific about what I trying to do)
Previously I said I want to "Add lines" to a existing JSON file.
What I want to do is simply add an element to an JSON object from a file, then save the file.
However I am still confused about how to do it.
The process I am guessing is to use ajax to load the content of the file (the JSON code in the file) into a variable then add the new element into the object then save the file.
I have seen a lot of code but are all just too confusing and looks like its for webpages. I am trying to edit a file on the computer as a program which I think webpage related code such as xmlhttp requests are irrelevant as the file is in a folder in appdata.
I have been confused and thought Java and Javascript were the same thing, I know now they're not.
What code or functions would I look for and how would it be used in the code?
(Please don't post pseudocode because I have no idea how to write the code for them since I have literally no idea how to code anything other than a html webpage and some php. Other coding language like Java, Javascript and Python I have little knowledge with but not enough to write a program alone.)

I think it would be best to use code that somebody else has already written to manipulate the JSON. There are plenty of libraries for that, and the best would be the officially specified one, JSON-P. What you would do is this:
Go to http://jsonp.java.net/ and download JSON-P. (You will have to examine the page carefully to find the link to "JSON Processing RI jar".) You will need to include this JAR in your class path while you write your program.
Add imports to your program for javax.json.*.
Write this code to do the job (you will have to catch JsonExceptions and IOExceptions):
JsonReader reader = Json.createReader(new FileReader("launcher_profiles.json"));
JsonObject file = reader.readObject();
reader.close();
JsonObject profiles = file.getJsonObject("profiles");
JsonObject newProfile = Json.createObjectBuilder()
.add("name", "New Lines")
.add("gameDir", "New Lines")
.add("lastVersionId", "New Lines")
.add("playerUUID", "")
.build();
JsonObjectBuilder objectBuilder = Json.createObjectBuilder()
.add("New Profile Name", newProfile);
for (java.util.Map.Entry<String, JsonValue> entry : profiles.entrySet())
objectBuilder.add(entry.getKey(), entry.getValue());
JsonObject newProfiles = objectBuilder.build();
// Now, figure out what I have done so far and write the rest of the code yourself! At the end, use this code to write out the new file:
JsonWriter writer = Json.createWriter(new FileWriter("launcher_profiles.json"));
writer.writeObject(newFile);
writer.close();

Parse serialized json payload in java

im struggling with json again :(
Here is the original response:
{"xml-fragment":{"workItem":{"#id":"251","#version":"74"},"presentation":{"#formIdenitifier":"1.0.0.201310151421/openspaceGWTPull_DefaultChannel/.default/Npda/NpdaProcess/UserReconcile/UserReconcile.gwt.json","#type":"GWT_FORM","#version":"1.0.0.201310151421","#activityName":"UserReconcile"},"workTypeDetail":{"#typePiled":"false","#pilingLimit":"0","#uid":"WT__RIoPEDWTEeOr4-yR8gXd7g","#version":"1.0.0.201310151421"},"payloadModel":{"serializedPayload":"{items:[{\"$param\":\"BankReconInput\",\"mode\":\"IN\",\"$value\":[{\"bankAccountTx_pk\":\"55213\",\"amount\":\"10099\",\"reference\":\"ImAmReference\",\"date\":\"2013-10-15\",\"reconType\":\"?\",\"amxcaseref\":\"pvm:0a12iq\",\"$type\":\"coza.npda.bom.BankTransaction\"}]}]}","#payloadMode":"JSON"}}}
i want to for example get value of amount from the serializedPayload. The problem is that it is not a json object. If i try:
obj = new JSONObject(jsonResp).getJSONObject("xml-fragment").getJSONObject("payloadModel");
this returns to me serializedPayload as a string and #payloadMode as a string.
i tried:
obj = new JSONObject(jsonResp).getJSONObject("xml-fragment").getJSONObject("payloadModel").getJSONObject("serializedPayload");
its confirms that serializedPayload is not a json object.
I looked at this example: http://developer.android.com/reference/org/json/JSONTokener.html
But its data is not as complex as mine and i am struggling to find java examples of how to do this.
Please can anyone help.

You don't need an example, you need to look at the JSON and think for a second.
serializedPayload is not a JSON object to begin with, it's really a string that has another piece of json encoded inside, sort of like the russian nesting dolls (frankly, it's an abomination).
You need to take the string, and then parse it again, using another JSONObject, sort of:
String payload = data..getJSONObject("xml-fragment").getJSONObject("payloadModel").getString("serializedPayload");
JSONObject theRealData = new JSONObject(payload);

Doing HTTP post of JSON object every second

I have to do a HTTP post in java every second after building a json object.
The json object is built from reading a CSV file which is huge (200Mbs+), so my problem is
how do I read x number of lines build x objects and post that every second(as it is not possible to parse the whole 200mb file in less than a second) and continue reading the next x lines.
Please let me know your thoughts..
Can I use Java timer class, and keep reading the CSV file and at the same time post the json object to the server every second with the formed json?

It is hardly possible to read, parse, convert and send a 200 MB file once per second.
So you need to change your design:
My suggestion would be to only send changed lines, something like this:
{
"1" : {"field1":"value1","field2":"value2"},
"17" : {"field1":"value1","field2":"value2"}
}
Which of course gives you new problems:
The client needs to figure out which lines have changed, and the server needs to integrate the changed lines with the existing data.

I would make it depending on the file size and not depending on time.
BufferedReader fin = null; //create it
Gson gson=new Gson(); //Google code open source library for JSON in Java
ArrayList<JSONObject> jsonList=new ArrayList<JSONObject>();
while (((line = fin.readLine()) != null)) {
if ( line.length()==0 ){
//"Blank line;
}else{
currJSON=loadJSON(line);//You have to load it in a Java Object
if ( jsonList.size()<MAX_JSON){
jsonList.add(currJSON);
}
if (JsonList.size()==MAX_JSON){ //Define the maximum size of the list you want to post
gson.toJson(jsonList); //Convert to JSON
//You should post your Json with some Http Connection to your server
jsonList.clear();