Convert string to json object using java

Question

I have a string data and i want to add it to json and retrive it to add it to excel. But its not happening Please kindly help this is my code....

String table = "[{"id":1,"name":"xxx","location":"xx"}{"id":2,"name":"yyy","location":"yy"}{"id":3,"name":"zzz","location":"zz"}]";

 JSONObject jObject = new JSONObject(table); // json String
 projectname = jObject.getString("name"); // get the name from data.
 System.out.println(projectname);

• Dennis Traub: That is not a valid String.
• Sneh: This question is already answered on this link. stackoverflow.com/questions/5245840/… Also this is not a valid string as Dennis suggested.
• subash: use POJO with ObjectMapper. that is quite simple and understandable..
• user2894607: sorry i have made a mistake adding question.. but in my code its proper

Answer 1

You can use JSONObject and JsonArray for this as shown below

JSONObject mainObj = new JSONObject();
 JSONArray somearr = new JSONArray();
 while (iter.hasnext()) {
 ClassName someObject=iter.next();
 JSONObject jsonobj = new JSONObject();
 jsonobj.put("id", id_from_someObject);;
 jsonobj.put("name", name_from_someObject);
 jsonobj.put("name", location_from_someObject);;
 somearr.put(seatObj);
 }
mainObj.put("response",somearr);
return mainObj.toString();

Answer 2

Simple and effective way i will tell you using json.org and jackson-mapper-asl first create a class suppose its name is Person

public class Person {
 private int id;
 private String name;
 private String location;
 //getters and setters
 @Override
 public String toString() {
 return "Person{" +
 "id=" + id +
 ", name='" + name + '\'' +
 ", location='" + location + '\'' +
 '}';
 }
}

create another class suppose mainclass

public static void main(String[] args) throws IOException, JSONException {
 String jsonString ="[{\"id\":1,\"name\":\"xxx\",\"location\":\"xx\"},
 {\"id\":2,\"name\":\"yyy\",\"location\":\"yy\"},
 {\"id\":3,\"name\":\"zzz\",\"location\":\"zz\"}]";
 ObjectMapper mapper = new ObjectMapper();
 JSONArray jsonArray = new JSONArray(jsonString);
 List<Person> listFromJsonArray = new ArrayList<Person>();
 for(int i =0 ;i<jsonArray.length();i++){
 String firstObjectAsString = jsonArray.get(i).toString();
 Person person = mapper.readValue(mapper.readTree(firstObjectAsString), 
 Person.class);
 listFromJsonArray.add(person);
 }
 System.out.println(listFromJsonArray);
}

Now using the list get the individual Person objects get the individual values using getters and do whatever you want

Answer 3

Well, you do have an error at defining your table string. I'm guessing you need

String table = "[{'id':1,'name':'xxx','location':'xx'}{'id':2,'name':'yyy','location':'yy'}{'id':3,'name':'zzz','location':'zz'}]";
JSONObject jObject = new JSONObject(table);

instead of

String table = [{"id":1,"name":"xxx","location":"xx"}{"id":2,"name":"yyy","location":"yy"}{"id":3,"name":"zzz","location":"zz"}];
JSONObject jObject = new JSONObject(table); 

• user2894607: i did same thing but its giving an error saying org.json.JSONException: A JSONObject text must begin with '{' at 1 [character 2 line 1]
• user2894607: yes i got, i add string table to JSONArray and then retrieved and added to JSONObject

Answer 4

You can try following code for parsing json object

String table = "{"keyElement" : {"id":1,"name":"xxx","location":"xx"}{"id":2,"name":"yyy","location":"yy"}{"id":3,"name":"zzz","location":"zz"}}";
JSONObject jObject = new JSONObject(table);
JSONArray array = jObject.getJSONArray("keyElement"); 
for(int i = 0 ; i < array.length() ; i++)
{
 System.out.println(array.getJSONObject(i).getString("id"));
 System.out.println(array.getJSONObject(i).getString("name"));
 System.out.println(array.getJSONObject(i).getString("location"));
}

Now You can get idea...