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JSONObject shows escape characters

I have a manual json object that i created and I use escape characters for one of the fields. I see escape strings whenever i print my jsonobject, is there a way to remove them? I'm just worried that the client will get the json object with the escaped strings when i send this over through the server.
String car_parameters = "{\"property_name\":\"car_id\",\"traceKey\":\"account_id,accountName,car_id\"}";
System.out.println("car params"+car_parameters);
JSONObject jsonObject = new JSONObject();
jsonObject.put("message", car_parameters);
System.out.println("one"+jsonObject);
System.out.println("two"+payload);
These are the outputs respectively, i tried converting json object to string but that did not make a difference.I'd expect to see json object's fields without escape characters like when i print out just the string.
car params{"property_name":"car_id","traceKey":"account_id,accountName,car_id"}
one{"message":"{\"property_name\":\"car_id\",\"traceKey\":\"account_id,accountName,car_id\"}"}
two{"message":"{\"property_name\":\"car_id\",\"traceKey\":\"account_id,accountName,car_id\"}"}

The escape character is caused by Java syntax. Java does not allow
String car_parameters = "{"property_name":"car_id","traceKey":"account_id,accountName,car_id"}"
is converted automatically.
You can turn it into an object, as shown below
System.out.println("toString"+JSONObject.parse(car_parameters));
output：
Object:{"traceKey":"account_id,accountName,car_id","property_name":"car_id"}
in addition：
If you send it to the client, it will also be {"message": "{property_ name":"car_ id","traceKey":"account_ id,accountName,car_ id"}"}
\It will become a part of the string, so the front end needs to handle it, but the transfer in Java does not affect the use.

You can do this. please consider what artifact you need.(My favorite is ObjectMapper.)
If you need generate from string, it is simple.
Maybe there is a lot of harsh way but I think it is not necessary now.
Remember that A first sample need new artifact as below in your pom.xml
<!-- for the JSONParser -->
<dependency>
<groupId>com.googlecode.json-simple</groupId>
<artifactId>json-simple</artifactId>
<version>1.1</version>
</dependency>
public void JSonTest() throws JSONException, ParseException {
String car_parameters = "{\"property_name\":\"car_id\",\"traceKey\":\"account_id,accountName,car_id\"}";
System.out.println("car params"+car_parameters);
JSONParser jsonParser = new JSONParser();
Object myObject = jsonParser.parse(car_parameters);
System.out.println("One" + myObject);
// Put it separate.
JSONObject jsonObject = new JSONObject();
jsonObject.put("property_name", "car_id");
jsonObject.put("traceKey", "account_id,accountName,car_id");
System.out.println("Two"+jsonObject);
jsonObject.remove("property_name");
jsonObject.remove("traceKey");
// Put it a map first.
HashMap<String, String> myMap = new HashMap<>();
myMap.put("property_name", "car_id");
myMap.put("traceKey", "account_id,accountName,car_id");
jsonObject.put("message", myMap);
System.out.println("Three"+jsonObject);
}
And Here is output,
car params{"property_name":"car_id","traceKey":"account_id,accountName,car_id"}
One{"traceKey":"account_id,accountName,car_id","property_name":"car_id"}
Two{"traceKey":"account_id,accountName,car_id","property_name":"car_id"}
Three{"message":"{traceKey=account_id,accountName,car_id, property_name=car_id}"}

Rest Assured code not allowing to use println

I am trying to automate twitter API. when tried to print "js.get("text") using
System.out.println(js.get("text")); I am getting error as
"The method println(boolean) is ambiguous for the type PrintStream"
I downloaded jars and passed in Build path as well "scribejava-apis-2.5.3" and "scribejava-core-4.2.0"
Below code is not allowing me use println for ------>js.get("text")
public class Basicfunc {
String Consumerkeys= "**************";
String Consumersecretkeys="*******************";
String Token="*******************";
String Tokensecret="***************************";
#Test
public void getLatestTweet(){
RestAssured.baseURI = "https://api.twitter.com/1.1/statuses";
Response res = given().auth().oauth(Consumerkeys, Consumersecretkeys, Token, Tokensecret).
queryParam("count","1").
when().get("/home_timeline.json").then().extract().response();
String response = res.asString();
System.out.println(response);
JsonPath js = new JsonPath(response);
System.out.println(js.get("text"));
}
}

Use System.out.println(js.getString("text")); instead of System.out.println(js.get("text"));, because get returns any primitive value.
I think your problem is that your twitter response is actually a list.
Try to use System.out.println(js.getList()[0].get("text")); and be aware that you are only using the first [0] entry and ignoring the rest.

how to manipulate HTTP json response data in Java

HttpGet getRequest=new HttpGet("/rest/auth/1/session/");
getRequest.setHeaders(headers);
httpResponse = httpclient.execute(target,getRequest);
entity = httpResponse.getEntity();
System.out.println(EntityUtils.toString(entity));
Output as follows in json format
----------------------------------------
{"session":{"name":"JSESSIONID","value":"5F736EF0A08ACFD7020E482B89910589"},"loginInfo":{"loginCount":50,"previousLoginTime":"2014-11-29T14:54:10.424+0530"}}
----------------------------------------
What I want to know is how to you can manipulate this data using Java without writing it to a file?
I want to print name, value in my code
Jackson library is preferred but any would do.
thanks in advance

You may use this JSON library to parse your json string into JSONObject and read value from that object as show below :
JSONObject json = new JSONObject(EntityUtils.toString(entity));
JSONObject sessionObj = json.getJSONObject("session");
System.out.println(sessionObj.getString("name"));
You need to read upto that object from where you want to read value. Here you want the value of name parameter which is inside that session object, so you first get the value of session as JSONObject using getJSONObject(KeyString) and read name value from that object using function getString(KeyString) as show above.
May this will help you.

Here's two ways to do it without a library.
NEW (better) Answer:
findInLine might work even better. (scannerName.findInLine(pattern);)
Maybe something like:
s.findInLine("{"session":{"name":"(\\w+)","value":"(\\w+)"},"loginInfo":{"loginCount":(\\d+),"previousLoginTime":"(\\w+)"}}");
w matches word characters (letters, digits, and underscore), d matches digits, and the + makes it match more than once (so it doesnt stop after just one character).
Read about patterns here https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html
OLD Answer:
I'm pretty sure you could use a scanner with a custom delimiter here.
Scanner s = new Scanner(input).useDelimiter("\"");
Should return something like:
{
session
:{
name
:
JSESSIONID
,
value
:
5F736EF0A08ACFD7020E482B89910589
And so on. Then just sort through that list/use a smarter delimiter/remove the unnecessary bits.
Getting rid of every other item is a pretty decent start.
https://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html has info on this.

I higly recomend http-request built on apache http api.
private static final HttpRequest<Map<String, Map<String, String>>> HTTP_REQUEST = HttpRequestBuilder.createGet(yourUri, new TypeReference<Map<String, Map<String, String>>>{})
.addDefaultHeaders(headers)
.build();
public void send(){
ResponseHandler<Map<String, Map<String, String>>> responseHandler = HTTP_REQUEST.execute();
Map<String, Map<String, String>> data = responseHandler.get();
}
If you want use jackson you can:
entity = httpResponse.getEntity();
ObjectMapper mapper = new ObjectMapper();
Map<String, Map<String, String>> data = mapper.readValue(entity.getContent(), new TypeReference<Map<String, Map<String, String>>>{});

Parsing JSON using GSON in java and populating a list view

I realize my questions have been asked a lot but I have spent a considerable amount of time scouring both SO and google trying to get a better understanding of this concept with no success. I've seen many different implementations, which is what leads me to get some advice about my specific situation.
MY OBJECTIVE
I need to perform a post request to a php file and the goal is to ultimately populate fields in a list activity with some of the json data.
HTTP POST RESPONSE
Here is the format of the response data I'm getting back from the server, which appears to be a JSON object of arrays(?).
{"expense":[{"cat_id_PK":237,"cat_name":"Name1","cat_amount":"100.00","is_recurring":0},
{"cat_id_PK":238,"cat_name":"Name2","cat_amount":"200.00","is_recurring":0},
{"cat_id_PK":239,"cat_name":"Name3","cat_amount":"300.00","is_recurring":0},
{"cat_id_PK":240,"cat_name":"Name4","cat_amount":"400.00","is_recurring":0}],
"expense_rec": [{"cat_id_PK":207,"cat_name":"Name5","cat_amount":"500.00","is_recurring":1}]}
FIRST QUESTION
The code below is what I'm using to read the response. Is this how I should be handling that? It seems weird to get a json encoded response and then change it to a string, only to try and access elements of a json object again. Am I on the wrong track here?
//This code is in the doInBackground method of my "sendPostRequest" async task.
HttpResponse httpResponse = httpClient.execute(httpPost);
InputStream inputStream = httpResponse.getEntity().getContent();
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
StringBuilder stringBuilder = new StringBuilder();
String bufferedStrChunk = null;
while ((bufferedStrChunk = bufferedReader.readLine()) != null) {
stringBuilder.append(bufferedStrChunk);
}
//Returns string to onPostExecute()
return stringBuilder.toString();
SECOND QUESTION
I have another file called "PostResponse.java" that holds the following code I modeled after a tutorial online. I'm unsure of how to interact with this class from the onPostExecute method. How can I access say, the first item in the first object (something like in PHP where you could do: expense[0]['cat_name']). I've tried to do this various ways with no success. Here is the PostResponse.java class:
public class PostResponse {
public Integer cat_id_PK;
public String cat_name;
public BigDecimal cat_amount;
public Integer is_recurring;
public int getID() {
return this.cat_id_PK;
}
public void setID(int cat_id_PK){
this.cat_id_PK = cat_id_PK;
}
public String getName() {
return this.cat_name;
}
public void setName(String cat_name) {
this.cat_name = cat_name;
}
public BigDecimal getAmount() {
return this.cat_amount;
}
public void setAmount(BigDecimal cat_amount) {
this.cat_amount = cat_amount;
}
public int getRecurring() {
return this.is_recurring;
}
public void setRecurring(int is_recurring) {
this.is_recurring = is_recurring;
}
#Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("*** Categories ***");
sb.append("cat_id_PK="+getID()+"\n");
sb.append("cat_name="+getName()+"\n");
sb.append("cat_amount="+getAmount()+"\n");
sb.append("is_recurring="+getRecurring()+"\n");
return sb.toString();
}
}
and here is the content of my onPostExecute method:
protected void onPostExecute(String result) {
super.onPostExecute(result);
Gson gson = new Gson();
PostResponse response = gson.fromJson(result, PostResponse.class);
System.out.println(result);
}
Like I said originally, my ultimate goal is to populate these items to a list activity, but at this point I'd settle for just knowing how to get at specific elements. However, if anyone would like to include how to populate a list activity in their response, it would save me a lot more headaches, as nothing with java is coming easy for me!

FIRST QUESTION
The code below is what I'm using to read the response. Is this how I should be handling that? It seems weird to get a json encoded response and then change it to a string, only to try and access elements of a json object again. Am I on the wrong track here?
It's one way of handling the http response. A "json encoded response" is little more than a text-based response, so converting it into a string on the receiving end would make sense. That is, the json you receive isn't an 'object' as far as Java is concerned: it's just textual representation of an object (or a bunch of objects in your case), received as a stream of bytes.
That being said, you can potentially shorten your code by skipping the string(builder) part. Gson provides an alternative constructor that takes a Reader instance, for which you can suppy the BufferedReader in your code snippet.
As a side note: the conversion of textual json into Java objects is a potentially 'heavy' operation. As such, you'd best avoid doing it on the main/ui thread, so just move it into the doInBackground() method of your AsyncTask (and change types appropriately).
SECOND QUESTION
I have another file called "PostResponse.java" that holds the following code I modeled after a tutorial online. I'm unsure of how to interact with this class from the onPostExecute method. How can I access say, the first item in the first object (something like in PHP where you could do: expense[0]['cat_name']). I've tried to do this various ways with no success.
You're close, but if you look more closely to the json sample, you'll see that your PostResponse class is not a good match for it:
{
"expense": [
{
"cat_id_PK": 237,
"cat_name": "Name1",
"cat_amount": "100.00",
"is_recurring": 0
},
{
"cat_id_PK": 238,
"cat_name": "Name2",
"cat_amount": "200.00",
"is_recurring": 0
},
{
"cat_id_PK": 239,
"cat_name": "Name3",
"cat_amount": "300.00",
"is_recurring": 0
},
{
"cat_id_PK": 240,
"cat_name": "Name4",
"cat_amount": "400.00",
"is_recurring": 0
}
],
"expense_rec": [
{
"cat_id_PK": 207,
"cat_name": "Name5",
"cat_amount": "500.00",
"is_recurring": 1
}
]
}
Consider the more hierarchical formatting above. On the first level there are two (json) objects: expense and expense_rec (both contain 0...* elements, as the square brackets indicate). That means that whatever class you're going to be trying to map the json onto, should define these fields too. If you now look at your PostResponse class, it should become obvious that in its current form it in fact models one of the child objects of the aforementioned fields.
Basically, the classes to map the json onto, should look somewhat like this:
PostResponse:
public class PostResponse {
public ExpenseItem[] expense;
public ExpenseItem[] expense_rec;
// List<ExpenseItem> is also supported
// getters & setters
}
ExpenseItem:
public class ExpenseItem {
public Integer cat_id_PK;
public String cat_name;
public BigDecimal cat_amount;
public Integer is_recurring;
// getters & setters
}
With the model classes defined, try to let Gson work its magic again. If all goes well, you should be able to access the data in a way similar to what you're used to in PHP:
// map json to POJOs
PostResponse response = new Gson().fromJson(bufferedReader, PostResponse.class);
// retrieve the cat_name for the first item (assuming there is one)
String catName = response.getExpense()[0].getName();
... or any of the other fields through the getters defined in ExpenseItem.
Once you have this part working, it's going to be fairly straightforward to supply the array or list of expenses to an adapter (have a look at ArrayAdapter in the Android framenwork) and bind that adapter to a ListView.

The answer is yes, you will get the response in InputStream
For your second question check this out - jsonschema2pojo this can be helpful while creating models for your JSON data.
Then to use GSON
Gson gson = new Gson();
YourObj yourObj = (YourObj) gson.fromJson(result, YourObj.class);

The answer is yes.Response is received as InputSteam
protected void onPostExecute(String result)
{
super.onPostExecute(result);
Gson gson = new Gson();
PostResponse response = gson.fromJson(result, PostResponse.class);
System.out.println(result);
}
This code section mostly means that after an AsyncTask that get web Response and get the String format json response,this onPostExecute will be called with that Stringfied json.
Gson gson = new Gson();
Gson is a library supported by Google for android to deserialization into your class OBject.
gson.fromJson(result, PostResponse.class);
This method is the real process of deserialization. result is Stringfied json and the second is the Target class you want to deserialize into.
This will return a PostResponse Object and you can use it now.

For the json data (
{"expense":[{"cat_id_PK":237,"cat_name":"Name1","cat_amount":"100.00","is_recurring":0},
{"cat_id_PK":238,"cat_name":"Name2","cat_amount":"200.00","is_recurring":0},
{"cat_id_PK":239,"cat_name":"Name3","cat_amount":"300.00","is_recurring":0},
{"cat_id_PK":240,"cat_name":"Name4","cat_amount":"400.00","is_recurring":0}],
"expense_rec": [{"cat_id_PK":207,"cat_name":"Name5","cat_amount":"500.00","is_recurring":1}]}),
it contains two different arrays here, one is "expense" and another is "expense_rec". So if you want to populate these items to a list activity, you can try the follow methods.
protected void onPostExecute(String result) {
super.onPostExecute(result);
JSONObject jsonObject = new JSONObject(builder.toString());
Log.i(TAG, "jsonObject is : " + jsonObject.toString());
//this is the first array data
JSONArray jsonArray = jsonObject.getJSONArray("expense");
Log.i(TAG, "Array length is: " + jsonArray.length());
for(int i = 0; i < jsonArray.length(); i++){
JSONObject jsoObj = jsonArray.getJSONObject(i);
String name = jsoObj.getString("cat_name");
Log.i(TAG, "file name is: " + name);
}
//this is the second array data
jsonArray = jsonObject.getJSONArray("expense_rec");
for(int i = 0; i < jsonArray.length(); i++){
JSONObject jsoObj = jsonArray.getJSONObject(i);
String name = jsoObj.getString("cat_name");
Log.i(TAG, "file name is: " + name);
}
}

Creating JSON objects directly from model classes in Java

I have some model classes like Customer, Product, etc. in my project which have several fields and their setter-getter methods, I need to exchange objects of these classes as a JSONObject via Sockets to and from client and server.
Is there any way I can create JSONObject directly from the object of model class such that fields of the object become keys and values of that model class object become values for this JSONObject.
Example:
Customer c = new Customer();
c.setName("Foo Bar");
c.setCity("Atlantis");
.....
/* More such setters and corresponding getters when I need the values */
.....
And I create JSON Object as:
JSONObject jsonc = new JSONObject(c); //I'll use this only once I'm done setting all values.
Which gets me something like:
{"name":"Foo Bar","city":"Atlantis"...}
Please note that, in some of my model classes, certain properties are itself an object of other model class. Such as:
Product p = new Product();
p.setName("FooBar Cookies");
p.setProductType("Food");
c.setBoughtProduct(p);
In a case like above, as I'd expect, the yielded JSON object would be:
{"name":"Foo Bar","city":"Atlantis","bought":{"productname":"FooBar Cookies","producttype":"food"}}
I know I could create something like toJSONString() in each model class and have the JSON-friendly string created and manipulate it then, but in my previous experiences of creating RESTful service in Java (which is totally out of context for this question), I could return JSON string from the service method by using #Produces(MediaType.APPLICATION_JSON) and have the method returning object of model class. So it produced JSON string, which I could consume at the client end.
I was wondering if it's possible to get similar behavior in current scenario.

Google GSON does this; I've used it on several projects and it's simple and works well. It can do the translation for simple objects with no intervention, but there's a mechanism for customizing the translation (in both directions,) as well.
Gson g = ...;
String jsonString = g.toJson(new Customer());

You can use Gson for that:
Maven dependency:
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.0</version>
</dependency>
Java code:
Customer customer = new Customer();
Product product = new Product();
// Set your values ...
Gson gson = new Gson();
String json = gson.toJson(customer);
Customer deserialized = gson.fromJson(json, Customer.class);

User = new User();
Gson gson = new Gson();
String jsonString = gson.toJson(user);
try {
JSONObject request = new JSONObject(jsonString);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

Use gson to achieve this. You can use following code to get the json then
Gson gson = new Gson();
String json = gson.toJson(yourObject);

I have used XStream Parser to
Product p = new Product();
p.setName("FooBar Cookies");
p.setProductType("Food");
c.setBoughtProduct(p);
XStream xstream = new XStream(new JettisonMappedXmlDriver());
xstream.setMode(XStream.NO_REFERENCES);
xstream.alias("p", Product.class);
String jSONMsg=xstream.toXML(product);
System.out.println(xstream.toXML(product));
Which will give you JSON string array.