my Json Strin is
{"result":[[{"Name":"Mos","Family":"Hos"},{"Name":"Mos","Family":"Hos"}]]}
i connect to rest server and get this string in java but i cant pars this string to a class in java with gson .
what class i need in Java for read this string.
JSon is a format that doesn't depend on the language. You can create it in Delphi/C/even code by yourself and read in any other language.
In Java its easy because there are a lot of thirdparties that handle this.
To name a few:
Jackson
JSON
JavaJSon
FlexJson
I'm sure there are others. I think the most widespread are gson and jackson
Hope this helps
you can use jackson api for this. may this link will help to achieve this.
Related
I would like to extract only the data present in a Json to JsonForm using Java.
Which framework can I use to this operation?
I've found the answer. Don't let the ugly aspect of JsonForm deceive you. I don't know if this apply for all cases, but I just had to extract the Json object that contains only the data. This can be done using any common Json parser, as like as Gson.
What is the easiest to use JSON Java library to parse a JSON (It's structure may vary so I can't mapp it to a Java class as I seen multiple libraries do it) update some elements in an array in this JSON and then save it back to disk?
There are so many libraries for JSON in Java (Gson, Jackson, etc.) and so complex that seem like a total overkill for what i need as opposed to other programming languages.
What's the most straightforward one to use? (that maybe also has a few examples on how to do this)
I have had great success with Json-Simple.
You can check it out here.
I used it to parse 1.5 Million Twitter Streaming data (which is in JSON).
You may find some sample code here on my blog.
You can use java-json jar. The docs for this jar can be found here
I use net.sf.json to do this.
here is an example :
String fromFile="{\"he\",\"hello\"}" //read from file instead
JSONObject object=(JSONObject)JSONSerializer.toJSON( fromFile );
object.put("he", "hello2");
System.out.println(object);
output:
{"he":"hello2"}
I would like to validate incoming json object for correctness at the server side. Is there a standard / optimal way to do that? What is your approach of validation?
My advice - deserialize the JSON and see if it breaks. For example, if you're using C# on the server side, you can use the newfangled DataContractJsonSerializer, or do it the old way with the JavaScriptSerializer which is arguably much simpler.
var serializer = new JavaScriptSerializer();
var result = serializer.Deserialize<Dictionary<string, object>>(jsonString);
EDIT: And now that it's come out that you're using Java, of course my C# example is not going to work for you, but the concept is the same. Stackoverflow already has some answers here: Convert a JSON string to object in Java ME?
Decode it with a JSON library. If it successfully decodes using a library that follows the specifications then it's valid.
Hello Im trying to pass an array of objects from javascript to java , but how can this be done..??
I've found in some posts that they do this using a hidden input. Is this the only way?
I'm a bit confused. Please tell me what do I need to do to pass my array to the server? and which javascript files and jars do I need to add?
Thanks in advance.
You seem to want a completely baked-in solution. Not sure I can provide that, but here's what I'd do.
Indeed use a hidden input field in a form, where the value of the field is a valid JSON string. Send the form to your server, and in your servlet use a JSON Java library to parse the JSON string.
Here json-lib, gson or Jackson would do. In your case, I'd say json-lib would seem the easiest to use.
To generate the JSON string on the client-side, either use a framework or custom solution. For instance, jQuery has a serialize() function to serialize a form's fields to a JSON object directly, which you can then convert to string. Other frameworks provide similar functions.
To learn more about JSON, be sure to read the JSON Wikipedia entry and to visit the official JSON page (which also gives you a Java implementation of the JSON data-interchange format, though maybe not the most efficient one for processing a lot of data). To make sure your generated JSON is valid, you can use JSONLint.
If the objects are simple enough, you can encode your array as a JSON string. Java has libraries to encode and decode JSON.
I want to read data from the database, convert it to docs (JSON) using Java.
Thanks
GSON is a Java library from Google to convert Java objects to JSON. You can simply pass a Java object to the library function and it will return a JSON string.
Download: http://code.google.com/p/google-gson/
Example: http://www.mkyong.com/java/how-do-convert-java-object-to-from-json-format-gson-api/
I have used the library from http://www.json.org, but the whole thing seems to be tedious to me. GSON is simple to use IMHO.
I would use JSONObject class:
http://www.json.org/javadoc/org/json/JSONObject.html
or you can build the string.