Escaping Special Character Java JSON

Question

Hi I am trying to send a JSON object to the server. The JSON object is :

JSONObject j = new JSONObject("{'Hobbies':" + h + "}");

{"Hobbies" : "Programming & Gaming"}

But as I SEND this object via HTTP it gives me an error Unterminated Object at character 22. After a lot of research I found out the '&' splits the object. Is there anyway I can escape '&'. I tried '\&' but it doesn't work as there is no escape sequence like that.

`After a lot of research I found out the '&' splits the object.` Show us your sources. What does _splits the object_ mean? — Sotirios Delimanolis, Aug 02 '14 at 21:19
@Sotirios Well apparently it does have some purpose if it breaks the JSON. — PurkkaKoodari, Aug 02 '14 at 21:22
@SotiriosDelimanolis The programme works just fine if there is no '&' present. Eg {"Hobbies" : "Programming"} this will work just fine but gives an error if I use '&' — Ishan Garg, Aug 02 '14 at 21:25
Just thought of something. If you send that JSON string value through HTTP, it'll break like this: `json={"foo":"bar & baz"}` to `json={"foo":"bar `and baz"}, effectively making `json` contain an unterminated JSON string. Pardon my formatting, the backticks seem to hate me. — PurkkaKoodari, Aug 02 '14 at 21:29
@Pietu Brings up a good point. Describe _as I send this object_. — Sotirios Delimanolis, Aug 02 '14 at 21:33
@Sotirios Actually figured out using [this question](http://stackoverflow.com/questions/11294107/how-can-i-send-the-ampersand-character-via-ajax) found via googling. The problem may be somewhere else, so not flagging a dupe. (not that it would be too much of one anyway.) — PurkkaKoodari, Aug 02 '14 at 21:36
Can you please be more detailed? How do you send it? In the body? As part of the query string? What gives you the error? What is the exact error? — Sotirios Delimanolis, Aug 02 '14 at 21:37
@SotiriosDelimanolis The exact error is : System.err org.json.JSONException : Unterminated Object at character 22 of {'Hobbies' : Programming & Gaming} — Ishan Garg, Aug 02 '14 at 21:44
Please edit your question and add it there with the full stacktrace. — Sotirios Delimanolis, Aug 02 '14 at 21:45
And that error is because the string value is not enclosed in quotes. Character 22 is at the end of "Programming". — Hot Licks, Aug 02 '14 at 21:50

Hot Licks · Accepted Answer · 2014-08-02T21:32:29.917

1

Go to json.org and study the syntax carefully. A key or string value in JSON must be enclosed in double quotes. Your code is generating

{'Hobbies' : Programming & Gaming}

To do it the way you're doing it you need to escape the double quotes:

new JSONObject("{\"Hobbies\":\"" + h + "\"}");

However, it would be far better to construct a JSONObject out of separate key and value. I'm not sure which specific Java JSON package you're using, but for most this would be simply:

new JSONObject("Hobbies", h);

edited Aug 02 '14 at 21:32

answered Aug 02 '14 at 21:24

Hot Licks

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This library is pretty bad and allows you to use the `String` literal `"{\"Hobbies\" : Programming & Gaming}"` as a JSON string. – Sotirios Delimanolis Aug 02 '14 at 21:26
@SotiriosDelimanolis - Yes, that's a valid string in JSON, but not valid JSON. It's just a string -- could just as well be "How now brown cow". – Hot Licks Aug 02 '14 at 21:29
I'm saying the parsing is very loose. It will not complain or fail given that value as its single constructor argument, although it is invalid JSON. – Sotirios Delimanolis Aug 02 '14 at 21:31
@SotiriosDelimanolis -- There are at least two different Java JSON packages that have the JSONObject class, so we don't know which is being used here. I would not trust one that treated `{"Hobbies" : Programming & Gaming}` as valid JSON, though. – Hot Licks Aug 02 '14 at 21:34
In any case, the parsing wouldn't fail at `&`. – Sotirios Delimanolis Aug 02 '14 at 21:36
@SotiriosDelimanolis so what do you use as a json library? I use `org.json` but I hear a lot about `GSON` and `Jackson` but Im not sure which one to use – meda Aug 02 '14 at 21:36
I've tried all `org.json` versions on [maven](http://mvnrepository.com/artifact/org.json/json) and they all pass at parsing the `String` value previously mentioned. – Sotirios Delimanolis Aug 02 '14 at 21:55
@HotLicks Yeah you were right I missed the quotes, the reason the '&' didn't work was without the quotes '&' was acting as a special character. – Ishan Garg Aug 02 '14 at 22:46

Escaping Special Character Java JSON

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