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How to read json with backslashes with Jackson

I'm calling 3rd party API and receiving as a response json:
{\"name\":\"name \\"A\\" and other\",\"id\":1}
If I try to map it like that I'm getting sure that:
Unexpected character ('\' (code 92)): was expecting double-quote to start field name
How could I map it with jackson? Should I remove backslashes with regex? Like every \" -> " and \\" -> \"

That is not well formed. What are you planning to do looks fine

File a bug against whoever is producing this broken output; it is not valid JSON.

{\"name\":\"name A and other\",\"id\":1}, this is the valid form of JSON or
{"name":"name A and other","id":1} it is also valid.
If this is not possible to do it, ask your vendor to validate the JSON structure

How to convert Json string with escape characters to json in Android

I am getting the following json as a reponse of a rest call. I am unable to parse it. Replacing "\" with "" doesn't work as the string contains many escape characters like "\n".
"[{\"message_id\":50870,\"message\":\"4d074d54-6e08-a140-fb7a-ee1300b01fbf.png\"},
{\"message_id\":50823,\"message\":\"1\\n2\\n3\\n4\\n5\\n6\"},{\"message_id\":50341,\"message\":\"I am getting a \\\"Server Error\\\" }]"
I have tried JsonTokener, UrlDecoder, but nothing seems to work.
I have also tried using
JsonString.replace ("\\"", "\"");
This works but is there a better way for conversion

JSONSerialiser serialiser = new JSONSerialiser();
String jsonOutput= serialiser.include("id","message").exclude("*").serialize(javaobject);
JSONObject jObject = JSONFactoryUtil.createJSONObject(jsonOutput);

Write correctly an URL in JSON with Java

I need to write an attribute on a JSON document, and this attribute is an URL
This is my code:
String url = "http://localhost:1028/accumulate";
JSONObject cabecera = new JSONObject();
cabecera.put("reference", url);
But when I create the JSON,this attibute is writted in this way:
"reference":"http:\/\/localhost:1028\/accumulate",
So, the service that receives the JSON String, it's sending me an error:
<subscribeContextResponse>
<subscribeError>
<errorCode>
<code>400</code>
<reasonPhrase>Bad Request</reasonPhrase>
<details>JSON Parse Error: <unspecified file>(1): invalid escape sequence</details>
</errorCode>
</subscribeError>
</subscribeContextResponse>
What is the correct way to write the URL??
Thanks in advance

But when I create the JSON,this attibute is writted in this way:
"reference":"http:\/\/localhost:1028\/accumulate",
That's fine, the backslashes are harmless, whatever you're using to serialize to JSON is just being a bit hyper with its escapes. The string represented by the above contains no backslashes at all, just slashes. \/ inside a JSON string is exactly the same as /, as we can see from the highlighted rule from http://json.org:
("solidus" is a fancy term for slash)

Jackson not escaping quotes in JSON

I'm trying to put a json in a javascript file in java, but when I write the json to a string, the string doesn't appear to be a valid json for javascript; it is missing some escapes. (This is happening in a string in the json which I formatted as a faux json.)
For example, this would be a valid json in my javascript file:
{
"message":
"the following books failed: [{\"book\": \"The Horse and his Boy\",\"author\": \"C.S. Lewis\"}, {\"book\": \"The Left Hand of Darkness\",\"author\": \"Ursula K. le Guin\"}, ]"
}
Here's what I get, though, where the double quotes aren't escaped:
{
"message":
"The following books failed: [{"book": "The Horse and his Boy","author": "C.S. Lewis"}, {"book": "The Left Hand of Darkness","author": "Ursula K. le Guin"}, ]"
}
I get the second result when I do this:
new ObjectMapper().writer().writeValueAsString(booksMessage);
But when I write it directly to a file with jackson, I get the first, good result:
new ObjectMapper().writer().writeValue(fileToWriteTo, booksMessage);
So why does jackson escape differently when writing to a file, and how do I get it to escape like that for me when writing to a string?

The writeValue() methods of the ObjectWriter class encode the input text.
You don't need to write to a file. An alternative approach for getting the same string could be:
StringWriter sw = new StringWriter();
new ObjectMapper().writer().writeValue(sw, booksMessage);
String result = sw.toString();

I added
booksJson = Pattern.compile("\\\\").matcher(booksJson).replaceAll("\\\\\\\\");
which escapes all the escape characters. That way when I write it to file and it removes the escapes, I still have the escapes I need. So turns out my real question was how to write to file without Java escapes being removed.

I'm very late to the party but I faced a similar problem and I realized it was not a problem with Jackson or my data. It was Java. I was reading from a JSON file and then trying to write it into a template HTML file.
I had a line my original JSON like yours, something like:
{"field" : "This field contains what looks like another JSON field: {\"abc\": \"value\"}"}
And when I wrote the above to a string, the backslash before the quotes in abc and value disappeared. I noticed that the contextual help for String.replaceAll mentioned something about Matcher.quoteReplacement. I went from this:
template = template.replaceAll("%template%", jsonDataString);
to this:
Pattern pattern = Pattern.compile("%template%");
Matcher matcher = Pattern.matcher(template);
matcher.replaceAll(matcher.quoteReplacement(jsonDataString));
Problem solved.
Matcher.quoteReplacement

Java : How to assign Json formated String to Java String?

I have a big json string which i will be getting as a request from the UI , which will be converted to a String and parsed .
I want to simulate the similar environment for testing locally , so for this purpose i captured the JSon format.
Currently i am manually adding "/" to this big json string .
Is there any other way to achieve this ??
For example i got this json
{"age":29,"messages":["msg 1","msg 2","msg 3"],"name":"Preethi"}
and converted that into
String str = "{\"age\":\"29\",\"messages\":[\"msg 1\",\"msg 2\",\"msg 3\"],\"name\":\"mkyong\"}";
Is there any other way to achieve this ??

On the client-side, do a search and regex "replace all" of double-quotes into single quotes on the desired form field before actually sending the request.

Actually, Java doesn't have verbatim string literals.
If you want a Java-like (and Java-VM-based) language that does, however, you might want to look at Groovy which has various forms of string literal.

we have in build method to convert jsonObject to string. Why don't you use that.
JSONObject json = new JSONObject();
json.toString();