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Convert string of valid JSON to JSON object in Java, so I can index into it

I have this string:
[{"row 0":[{},{},{},{},{},{},{},{}]},{"row 1":[{},{},{},{},{},{},{},{}]},{"row 2":[{},{},{},{},{},{},{},{}]},{"row 3":[{},{},{},{},{},{},{},{}]},{"row 4":[{"column 0":"WhitePawn"},{},{},{},{},{},{},{}]},{"row 5":[{},{},{},{},{},{},{},{}]},{"row 6":[{},{},{},{},{},{},{},{}]},{"row 7":[{},{},{},{},{},{},{},{}]}]
^ it's currently a String, let's call it string.
I'm trying to convert it into JSON like so:
new JSONObject(string);
but it isn't working. How to do this in Java?
Code looks like so:
private void parseMessageRedrawBoard(String message) {
Log.d("0000: ", message);
String trimmed = message.substring(message.indexOf("["));
Log.d("1111: ", trimmed);
JSONObject jsonObject = null;
try {
jsonObject = new JSONObject(trimmed);
Log.d("maybe worked...", "~");
} catch (Exception e) {
Log.d("dammit: ", e.getMessage());
}
}

You are trimming the string and turning it into an invalid JSON.
Your JSON starts with a "[" that indicates it is an array. If it starts with "{" you can assume that is an object.
So, as your JSON is an array, you can parse this exact content you mentioned with:
JSONArray jsonArray = new JSONArray(string);
And access the elements like in a List:
jsonArray.get(0);

Java: Loop through JSON string (cant convert to JsonArray (gson)

i get a json object via an api:
Gson gson = new Gson();
JsonObject users = gson.fromJson(reader, JsonObject.class)
this is my json object:
{"users":"[{\"user_id\": \"100011\", \"name\": \"Tim Clark\"}, {\"user_id\": \"100083\", \"name\": \"Timmy Kent\"}]"}
and i try to loop through all users
JsonArray usersArray = users.getAsJsonArray();
for (JsonElement ua : usersArray) {
JsonObject ua = ua.getAsJsonObject();
String name = ua.get("name").getAsString();
System.out.println(name);
}
also tried this
JsonArray usersArray = users.get("users").getAsJsonArray();
for (JsonElement ua : usersArray) {
JsonObject ua = ua.getAsJsonObject();
String name = ua.get("name").getAsString();
System.out.println(name);
}
But I get always exceptions like this
java.lang.IllegalStateException: Not a JSON Array: "[{\"user_id\": \"100011\", \" ....
In my opinion it is a valid json array, what to I miss?

Your JsonArray is between quotes: it's evaluated as a String
{"users":[{\"user_id\": \"100011\", \"name\": \"Tim Clark\"}, {\"user_id\":
\"100083\", \"name\": \"Timmy Kent\"}]}
should work (quotes inside the array don't need to be escapted as well, like "users")

extract from JSON

"biodata": {
"Ruby": {
"Expertise": "web development",
"EXperience": "5 years"
},
"Dylon": {
"Expertise": "Java",
"EXperience": "2 years"
}
}
I have the above JSONObject . I am trying to fetch some keys here .
I am looking to fetch the name key i.e Ruby , Dylon etc .
I am then trying to fetch the "Experience " key value .
Desired output :
name= Ruby
Experience = 5 years
My code :
JSONParser parser = new JSONParser();
Object obj = parser.parse(new FileReader("path to JSON file"));
JSONObject jsonobj = (JSONObject) obj;
String statistics = jsonobj.getString("biodata"); //The method getString(String) is undefined for the type JSONObject
for (Iterator key = jsonobj.keys(); itr.hasNext();) {//The method keys() is undefined for the type JSONObject //itr cannot be resolved
JSONObject name = jsonobj.get(key.next()); //Type mismatch: cannot convert from Object to JSONObject
String key = key.next();//The method next() is undefined for the type String
JSONObject name = jsonobj.get(key); //Type mismatch: cannot convert from Object to JSONObject
Log.d("data", "key="+key+ " and value="+jsonobj.toString()); //Log cannot be resolved
}
I have mentioned the errors in the comment of my code .

You json is not valid .
You should change to this .
{
"biodata": {
"Ruby": {
"Expertise": "web development",
"EXperience": "5 years"
},
"Dylon": {
"Expertise": "Java",
"EXperience": "2 years"
}
}
}
Try this .
private void jsonParse() {
try {
// use jsonobject to parse json with
JSONParser parser = new JSONParser();
Object obj = parser.parse(new FileReader("path to JSON file"));
JSONObject jsonObject = (JSONObject) obj;
// get jsonobject by biodata tag
JSONObject biodata = jsonObject.getJSONObject("biodata");
// use Iterator to get name
Iterator<String> names = biodata.keys();
// use while loop
while (names.hasNext()) {
// get name
String name = names.next().toString();
Log.d("data", "name=" + name);
// get jsonobject by name tag
JSONObject nameJsonObject = biodata.getJSONObject(name);
// get string
String Expertise = nameJsonObject.getString("Expertise");
String EXperience = nameJsonObject.getString("EXperience");
Log.d("data", "Experience =" + EXperience);
}
} catch (JSONException e) {
e.printStackTrace();
}
}

You have many issues in your code.
First: Assuming you want to implement code based on your current JSON String
Issues:
JSONObject API do not facilitate the methods of Map used in your implementation.
Your JSON String is not a array so for loop is not going to help, instead you should fetch the inner JSONObjects using the getJSONObject () method of the JSONObject API.
Casting the parsed object from your parser API will not automatically make it a JSONObject, the right way of doing this as below:
JsonObject jsonObject = parser.parse(new FileReader("path to JSON file")).getAsJsonObject();
Second: Assuming you intent to implement the JSON string representation as array, you should correct your JSON string as below.
"biodata": [{ "Ruby": { "Expertise": "web development", "EXperience": "5 years" }}, {"Dylon": { "Expertise": "Java", "EXperience": "2 years" } }]
With the above JSON string you can implement the fetching of data logic using JSONArray API

Reading JSON from Java

I have this JSON structure:
{"metrics":[{
"type": "sum",
"column": ["rsales", "nsales"]
},
{
"type":"count",
"column":["ptype", "plan"]
}]
}
I am trying to read that JSON from Java and want to the output to be like:
str_sum="Sum"
str_sum_array[]= {"rsales" ,"nsales"}
str_count="count"
str_count_array[]= {"ptype" ,"plan"}
Here is my code so far:
JSONArray jsonArray_Metric = (JSONArray) queryType.get("metrics");
for (int i = 0; i < jsonArray_Metric.length(); i++) {
JSONObject json_Metric = jsonArray_Metric.getJSONObject(i);
Iterator<String> keys_Metrict = json_Metric.keys();
while (keys_Metrict.hasNext()) {
String key_Metric = keys_Metrict.next();
// plz help
}
}
How can I complete the code to produce the desired output?

Instead of using iterator you can use simple for-loop as below ..
JSONParser parser = new JSONParser();
JSONObject object = (JSONObject) parser.parse(queryType);
JSONArray jsonArray_Metric = (JSONArray) object.get("metrics");
for (int index = 0; index < jsonArray_Metric.size(); index++) {
JSONObject item = (JSONObject) jsonArray_Metric.get(index);
String type = (String) item.get("type");
JSONArray column = (JSONArray) item.get("column");
System.out.println("str_sum store=\"" + type + "\"");
System.out.println("str_count_array[] store=" + column);
}
Sample Run
str_sum store="sum"
str_count_array[] store=["rsales","nsales"]
str_sum store="count"
str_count_array[] store=["ptype","plan"]
If you want JSONArray to be displayed with curly braces instead of default (actual) braces i.e. square braces then you could so something like this while printing or you can even delete them by replacing them with empty string "".
System.out.println("str_count_array[] store " + column.toString().replace("[", "{").replace("]", "}"));
You can format your display code as you like by playing around with println statement.

Parse Json In Java How to read Inner Value

Very New with Java Development Parsing JSON in JAVA Here is my Code.
package com.zenga.control;
import java.io.BufferedReader;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.methods.GetMethod;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;
public class Start {
public String readUrl(String urlString) {
String jsonString = null;
try {
HttpClient client = new HttpClient();
GetMethod get = new GetMethod(urlString);
client.executeMethod(get);
jsonString = get.getResponseBodyAsString();
}catch(Exception e) {
}
return jsonString;
}
public void getAddAsBeanObject() {
try {
String jsonString = new Start().readUrl("http://myDomain/JsonZ.json");
JSONObject obj = (JSONObject) JSONSerializer.toJSON(jsonString);
System.out.println(obj);
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
new Start().getAddAsBeanObject();
}
}
As I successfully Read Value in JSONObject and it also showing all JSON String on console But How can i Get Value For ID and UID and DURATION ?
Here The JSONString the i read in System.out.println(obj);
{
"Demo": {
"CONTENT": [
{
"ID": " 283 ",
"UID": " 87897bc8-ae9b-11e1-bdcf-123141042154 ",
"DURATION": "Full"
},
{
"ID": " 283 ",
"UID": " 87897bc8-ae9b-11e1-bdcf-123141042154 ",
"DURATION": "Full"
}
]
}
}

Following code can be used to iterate the JSON objects inside the JSON array 'CONTENT', using .get(java.lang.String) as documented, to pull the value out of the JSONObject.
I have only demonstrated how to get the ID but the same logic applies to the other values.
JSONObject obj = (JSONObject) JSONSerializer.toJSON(jsonString);
JSONArray content = obj.getJSONObject("Demo").getJSONArray("CONTENT");
java.util.Iterator<?> iterator = content.iterator();
while (iterator.hasNext()) {
JSONObject o = (JSONObject) iterator.next();
System.out.println(o);
System.out.println(o.get("ID"));
// etc...
}

Following is a sample code to reach the array`s inner objects specific to pattern you have provided.
String str = "{"+
"\"Demo\": {"+
"\"CONTENT\": ["+
" {"+
"\"ID\": \" 283 \","+
"\"UID\": \" 87897bc8-ae9b-11e1-bdcf-123141042154 \","+
"\"DURATION\": \"Full\""+
" },"+
"{"+
"\"ID\": \" 283 \","+
"\"UID\": \" 87897bc8-ae9b-11e1-bdcf-123141042154 \","+
"\"DURATION\": \"Full\""+
" }"+
"]"+
"}"+
"}";
try {
JSONObject jsr = new JSONObject(str); // JSON object with above data
JSONObject demo = jsr.getJSONObject("Demo"); // get Demo which is a JSON object inside jsr.
JSONArray content = demo.getJSONArray("CONTENT");// get CONTENT which is Json array inside Demo
for (int i = 0; i < content.length(); i++) { // iterate over array to get inner JSON objects and extract values inside
JSONObject record = content.getJSONObject(i); // each item of Array is a JSON object
String ID = record.getString("ID");
String UID = record.getString("UID");
String DURATION = record.getString("DURATION");
}
}
catch (JSONException e) {
e.printStackTrace();
}
Note: Above code is specifc to org.Json API. Find appropriate methods in library you are using for Json handling

Use a loop that iterates through the Json Object and access each of the element
for(/**loop until the counter reaches the size of the json object**/) {
//Access each element based on the ID as below.
System.out.println(Demo.CONTENT[CurrentCounter].ID); //here CurrentCounter is index
System.out.println(Demo.CONTENT[CurrentCounter].UID); ..... //read through all ids
}

I guess you could use the 'get' Method on the JSONObject. If you don't know which key to look for, I suggest using a Method that returns all available keys, like the one called 'keys'. With these values, you could then traverse down in you structure. See here:
http://json-lib.sourceforge.net/apidocs/net/sf/json/JSONObject.html

I guess GSON will be a big help for you.
See here Parsing json object into a string
There is a samplecode as well

Create a class which have variables you want to read from json string.And Gson will handle the rest.
https://code.google.com/p/google-gson/
Example usage:
//convert the json string back to object
DataObject obj = gson.fromJson(br, DataObject.class);