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How to remove html tags when getting reponse using HttpURLConnection and org.json library in Java?

I am using the following code to retreive information from API
HttpURLConnection connection;
..
reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
while ((line = reader.readLine()) != null) {
responseContent.append(line);
}
reader.close();
Then I convert the reponse to string
String responseBody = responseContent.toString();
After that I use org.json library to parse the information
JSONObject ob = new JSONObject(responseBody);
JSONArray Information = ob.getJSONArray("info");
for (int i = 0; i < Information.length(); i++) {
JSONObject data= Information.getJSONObject(i);
String dataName= data.getString("data_name");
}
As result I obtained some texts with html tags when I print dataName values, for example:
content name<sup></sup>

Solved
I used the Java Jsoup library to read the HTML tags.
Best regards.

How to access the nested field in json using Java?

I have a big JSON file(demo.json). Here is how it looks like:
{
"preview":false,
"result":{
"search_term":"rania",
"request_time":"Sat Apr 01 12:47:04 -0400 2017",
"request_ip":"127.0.0.1",
"stats_type":"stats",
"upi":"355658761",
"unit":"DR",
"job_title":"Communications Officer",
"vpu":"INP",
"organization":"73",
"city":"Wash",
"country":"DC",
"title":"Tom",
"url":"www.demo.com",
"tab_name":"People-Tab",
"page_name":"PEOPLE",
"result_number":"5",
"page_num":"0",
"session_id":"df234f468cb3fe8be",
"total_results":"5",
"filter":"qterm=rina",
"_time":"2017-04-01T12:47:04.000-0400"
}
}
{"preview"......}
{"preview"......}
....
I would like to access search term and page_name which is inside of the result and convert them into the string . Below is my java code which is not working:
BufferedReader br = new BufferedReader(new FileReader("demo.json"));
String line;
while ((line = br.readLine()) != null) {
JSONParser parser = new JSONParser();
Object obj = parser.parse(line);
JSONObject jsonObject = (JSONObject) obj;
String searchterm= (String) jsonObject.get("search_term");
String page_name = (String) jsonObject.get("page_name");
}
I am not familiar with how to access the nested fields and convert those into string. Any help is appreciated.

boolean preview = jsonObject.get("preview");
JSONObject result = jsonObject.getJSONObject("result");
String search_term = result.getString("search_term");
String page_name = result.getString("page_name");

You can use library like Gson .Convert the data into Map
BufferedReader br = new BufferedReader(new FileReader("demo.json"));
String line;
StringBuilder builder=new StringBuilder();
while ((line = br.readLine()) != null) {
builder.append(line);
}
Type type = new TypeToken<Map<String, String>>(){}.getType();
Map<String, String> myMap = gson.fromJson(builder.toString(), type);
You can use myMap to get Values for json Keys . For nested Key you can another convert it to Map again.

Use ObjectMapper to convert your JSON to PoJo and then use it.

Parsing JSON response(includes a list) in java

I did a http client and I'm getting a response. I am using a JSONObject to parse the data and when I execute the code below it prints out all of the JSON just fine
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
if(entity!=null){
try(InputStream instream = entity.getContent()) {
String responseString = readInputStream(instream);
JSONObject job = new JSONObject(responseString);
statusLabel.setText("Command Result: " + job.toString());
Here is the readInputSream function:
static private String readInputStream(InputStream inputStream) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(
inputStream, "UTF-8"));
String tmp;
StringBuilder sb = new StringBuilder();
while ((tmp = reader.readLine()) != null) {
sb.append(tmp).append("\n");
}
if (sb.length() > 0 && sb.charAt(sb.length() - 1) == '\n') {
sb.setLength(sb.length() - 1);
}
reader.close();
return sb.toString();
}
If I change it from job.toString() to:
statusLabel.setText("Command Result: " + job.get("result"));
it prints a 1 which is correct, it works all the way up to my_list. I'm not sure how to parse the list. I put a snippet of the response below. Ive tried "my_list", "my_list[]", my_list[0]" which none have worked. I get JSONObject "blank" not found
{"result":1, "ver":1,"total":2,"catch":true,"my_list":[{"id":3,"mid":0,"format":3,"user":4,"property":1,"type":0,"title":"hello","start":146,"end":1464,"hid":3,"bid":1,"reason":1,"time":0,"creator":"1","hello":0,"my":0,"year":"0","ggg":614,"name":"","ch":"0","attr":0,"type":1,"vtype":1,"tm_log": {"fr":4,"action":0,"vr":"82","started":1,"av_ended":2,"tr":1}}

The element you trying to retrieve is parsed into a JSONArray, not a JSONObject. Try:
JSONArray my_list = job.getJSONArray("my_list");

Assuming that you are using json parser project JSON-java to parse your JSON you need to retrieve a JSONArray instance - this is how arrays are storred in JSONObject. so do the following: JSONArray my_list = job.getJSONArray("my_list"); and then use methods of JSONArray class to access your array. The Javadoc to JSON-java package can be found here: http://stleary.github.io/JSON-java/index.html. Also note that JSON-java is very simple and easy to use JSON parser project but it is not very efficient for any serious project. Common recommendation for commercial use is Jackson JSON Processor which is one of the fastest and powerful JSON parsers. Here are some links to read about it: https://github.com/FasterXML/jackson, http://wiki.fasterxml.com/JacksonHome

AutoSuggest in Android from jsonencoded array of php

I want to use json encoded array which i am return from this link :
http://sids.roundone.asia/suggest.json?data=soft
as suggestions in android application.
(I have used json_encode($arr) function in php file and i am returning that as response for above link)
I have a problem in reading this response in java and storing it in an ArrayList.
My code is :
try {
String temp=sName.replace(" ", "%20");
URL js = new URL("https://sids.roundone.asia/suggest.json?data="+temp);
URLConnection jc = js.openConnection();
BufferedReader reader = new BufferedReader(new InputStreamReader(jc.getInputStream()));
String line = reader.readLine();
JSONObject jsonResponse = new JSONObject(line);
JSONArray jsonArray = jsonResponse.getJSONArray("results");
for(int i = 0; i < jsonResponse.length(); i++){
JSONObject r = jsonArray.getJSONObject(i);
ListData.add(new SuggestGetSet(jsonResponse.get(String.vlaueOf(iss)));
}
}

As I could see on your link, you're returning a JSON Array, instead of a JSON Object, ( "[ ]" instead of "{ }") and then in your java code you're trying to create a JSONObject here:
JSONObject jsonResponse = new JSONObject(line);
Try changing that to:
JSONArray jsonResponse = new JSONArray(line);

You return JSON array directly not a JSON Object have inner array so cast your incoming response to JSONArray directly.
JSONArray jsonResponse = new JSONArray(line);

Convert a .json file to a JSONArray

I used cURL to get some twitter feeds in the form of a json file ("twitter-feed.json"). I want to convert this json file to a JSONArray object. How do I do it?
I am new to Java and json. Your suggestions are most welcome.
FileInputStream infile = new FileInputStream("input/twitter-feed.json");
// parse JSON
JSONArray jsonArray = new JSONArray(string);
// use
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
System.out.println(jsonObject.getString("id"));
System.out.println(jsonObject.getString("text"));
System.out.println(jsonObject.getString("created_at"));
}
Thanks,
PD.

You need to read the file first, convert it to String then feed it to the JSONArray (I am assuming that you are using the JSON-Java Project. The code below illustrates how to read the file and set it to JSONArray
// read the source file, source comes from streaming API delimited by newline
// done by curl https://stream.twitter.com/1/statuses/sample.json?delimited=newline -utwitterUsername:twitterPasswd
// > /Projects/StackOverflow/src/so7655570/twitter.json
FileReader f = new FileReader("/Projects/StackOverflow/src/so7655570/twitter.json");
BufferedReader br = new BufferedReader(f);
ArrayList jsonObjectArray = new ArrayList();
String currentJSONString = "";
// read the file, since I ask for newline separation, it's easier for BufferedReader
// to separate each String
while( (currentJSONString = br.readLine()) != null ) {
// create new JSONObject
JSONObject currentObject = new JSONObject(currentJSONString);
// there are more than one way to do this, right now what I am doing is adding
// each JSONObject to an ArrayList
jsonObjectArray.add(currentObject);
}
for (int i = 0; i < jsonObjectArray.size(); i++) {
JSONObject jsonObject = jsonObjectArray.get(i);
// check if it has valid ID as delete won't have one
// sample of JSON for delete :
// {"delete":{"status":{"user_id_str":"50269460","id_str":"121202089660661760","id":121202089660661760,"user_id":50269460}}}
if(jsonObject.has("id")) {
System.out.println(jsonObject.getInt("id"));
System.out.println(jsonObject.getString("text"));
System.out.println(jsonObject.getString("created_at") + "\n");
}
}
Steps explanation :
Stream API does not provide valid JSON as a whole but rather a valid one specified by the delimited field. Which is why, you can't just parse the entire result as is.
In order to parse the JSON, I use the delimited to use newline since BufferedReader has a method readLine that we could directly use to get each JSONObject
Once I get each valid JSON from each line, I create JSONObject and add it to the ArrayList
I then iterate each JSONObject in the ArrayList and print out the result. Note that if you want to use the result immediately and don't have the need to use it later, you can do the processing itself in while loop without storing them in the ArrayList which change the code to:
// read the source file, source comes from streaming API
// done by curl https://stream.twitter.com/1/statuses/sample.json?delimited=newline -utwitterUsername:twitterPasswd
// > /Projects/StackOverflow/src/so7655570/twitter.json
FileReader f = new FileReader("/Projects/StackOverflow/src/so7655570/twitter.json");
BufferedReader br = new BufferedReader(f);
String currentJSONString = "";
// read the file, since I ask for newline separation, it's easier for BufferedReader
// to separate each String
while( (currentJSONString = br.readLine()) != null ) {
// create new JSONObject
JSONObject currentObject = new JSONObject(currentJSONString);
// check if it has valid ID as delete status won't have one
if(currentObject.has("id")) {
System.out.println(currentObject.getInt("id"));
System.out.println(currentObject.getString("text"));
System.out.println(currentObject.getString("created_at") + "\n");
}
}

You may try Gson:
For just arrays you can use:
Gson gson = new Gson();
//(Deserialization)
int[] ints2 = gson.fromJson("[1,2,3,4,5]", int[].class);
To deserialize an array of objects, you can just do:
Container container = new Gson().fromJson(json, Container.class);
As shown here

Use ObjectMapper Class from jackson library like this :
//JSON from file to Object
Staff obj = mapper.readValue(new File("c:\\file.json"), Staff.class);
//JSON from URL to Object
Staff obj = mapper.readValue(new URL("http://mkyong.com/api/staff.json"), Staff.class);
//JSON from String to Object
Staff obj = mapper.readValue(jsonInString, Staff.class);