JSONObject and JSONArray are the two common classes usually available in most of the JSON processing libraries. A JSONObject stores unordered key-value pairs, much like a Java Map implementation. A JSONArray, on the other hand, is an ordered sequence of values much like a List or a Vector in Java.
A JSONArray is an ordered sequence of values. Its external text form is a string wrapped in square brackets with commas separating the values. The internal form is an object having get and opt methods for accessing the values by index, and put methods for adding or replacing values.
You can check the character at the first position of the String (after trimming away whitespace, as it is allowed in valid JSON). If it is a { , you are dealing with a JSONObject , if it is a [ , you are dealing with a JSONArray .
Here is some code using java 6 to get you started:
JSONObject jo = new JSONObject();
jo.put("firstName", "John");
jo.put("lastName", "Doe");
JSONArray ja = new JSONArray();
ja.put(jo);
JSONObject mainObj = new JSONObject();
mainObj.put("employees", ja);
Edit: Since there has been a lot of confusion about put
vs add
here I will attempt to explain the difference. In java 6 org.json.JSONArray contains the put
method and in java 7 javax.json contains the add
method.
An example of this using the builder pattern in java 7 looks something like this:
JsonObject jo = Json.createObjectBuilder()
.add("employees", Json.createArrayBuilder()
.add(Json.createObjectBuilder()
.add("firstName", "John")
.add("lastName", "Doe")))
.build();
I suppose you're getting this JSON from a server or a file, and you want to create a JSONArray object out of it.
String strJSON = ""; // your string goes here
JSONArray jArray = (JSONArray) new JSONTokener(strJSON).nextValue();
// once you get the array, you may check items like
JSONOBject jObject = jArray.getJSONObject(0);
Hope this helps :)
Small reusable method can be written for creating person json object to avoid duplicate code
JSONObject getPerson(String firstName, String lastName){
JSONObject person = new JSONObject();
person .put("firstName", firstName);
person .put("lastName", lastName);
return person ;
}
public JSONObject getJsonResponse(){
JSONArray employees = new JSONArray();
employees.put(getPerson("John","Doe"));
employees.put(getPerson("Anna","Smith"));
employees.put(getPerson("Peter","Jones"));
JSONArray managers = new JSONArray();
managers.put(getPerson("John","Doe"));
managers.put(getPerson("Anna","Smith"));
managers.put(getPerson("Peter","Jones"));
JSONObject response= new JSONObject();
response.put("employees", employees );
response.put("manager", managers );
return response;
}
Please try this ... hope it helps
JSONObject jsonObj1=null;
JSONObject jsonObj2=null;
JSONArray array=new JSONArray();
JSONArray array2=new JSONArray();
jsonObj1=new JSONObject();
jsonObj2=new JSONObject();
array.put(new JSONObject().put("firstName", "John").put("lastName","Doe"))
.put(new JSONObject().put("firstName", "Anna").put("v", "Smith"))
.put(new JSONObject().put("firstName", "Peter").put("v", "Jones"));
array2.put(new JSONObject().put("firstName", "John").put("lastName","Doe"))
.put(new JSONObject().put("firstName", "Anna").put("v", "Smith"))
.put(new JSONObject().put("firstName", "Peter").put("v", "Jones"));
jsonObj1.put("employees", array);
jsonObj1.put("manager", array2);
Response response = null;
response = Response.status(Status.OK).entity(jsonObj1.toString()).build();
return response;
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