Something like this:
ArrayList<String> jsonStringToArray(String jsonString) throws JSONException {
ArrayList<String> stringArray = new ArrayList<String>();
JSONArray jsonArray = new JSONArray(jsonString);
for (int i = 0; i < jsonArray.length(); i++) {
stringArray.add(jsonArray.getString(i));
}
return stringArray;
}
Answer from Prizoff on Stack OverflowSomething like this:
ArrayList<String> jsonStringToArray(String jsonString) throws JSONException {
ArrayList<String> stringArray = new ArrayList<String>();
JSONArray jsonArray = new JSONArray(jsonString);
for (int i = 0; i < jsonArray.length(); i++) {
stringArray.add(jsonArray.getString(i));
}
return stringArray;
}
You could try something like:
new JSONArray(jsonString)
or if it is a property:
jsonObject.getJSONArray(propertyName)
Here you get JSONObject so change this line:
JSONArray jsonArray = new JSONArray(readlocationFeed);
with following:
JSONObject jsnobject = new JSONObject(readlocationFeed);
and after
JSONArray jsonArray = jsnobject.getJSONArray("locations");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject explrObject = jsonArray.getJSONObject(i);
}
Input String
[
{
"userName": "sandeep",
"age": 30
},
{
"userName": "vivan",
"age": 5
}
]
Simple Way to Convert String to JSON
public class Test
{
public static void main(String[] args) throws JSONException
{
String data = "[{\"userName\": \"sandeep\",\"age\":30},{\"userName\": \"vivan\",\"age\":5}] ";
JSONArray jsonArr = new JSONArray(data);
for (int i = 0; i < jsonArr.length(); i++)
{
JSONObject jsonObj = jsonArr.getJSONObject(i);
System.out.println(jsonObj);
}
}
}
Output
{"userName":"sandeep","age":30}
{"userName":"vivan","age":5}
The problem is not the JSONArray.toString(), as @Selvin mentioned.
From JSONArray source:
/**
* Encodes this array as a compact JSON string, such as:
* <pre>[94043,90210]</pre>
*/
@Override public String toString() {
try {
JSONStringer stringer = new JSONStringer();
writeTo(stringer);
return stringer.toString();
} catch (JSONException e) {
return null;
}
}
/**
* Encodes this array as a human readable JSON string for debugging, such
* as:
* <pre>
* [
* 94043,
* 90210
* ]</pre>
*
* @param indentSpaces the number of spaces to indent for each level of
* nesting.
*/
public String toString(int indentSpaces) throws JSONException {
JSONStringer stringer = new JSONStringer(indentSpaces);
writeTo(stringer);
return stringer.toString();
}
The problem is that you need to convert your ChecklistAnswer to JSON object first for your JSONArray to work properly.
Again from Javadoc:
/**
* A dense indexed sequence of values. Values may be any mix of
* {@link JSONObject JSONObjects}, other {@link JSONArray JSONArrays}, Strings,
* Booleans, Integers, Longs, Doubles, {@code null} or {@link JSONObject#NULL}.
* Values may not be {@link Double#isNaN() NaNs}, {@link Double#isInfinite()
* infinities}, or of any type not listed here.
...
In my ChecklistAnwer class i added:
public JSONObject toJsonObject(){
JSONObject json = new JSONObject();
try {
json.put("questionId", questionId);
json.put("checklistId", checklistId);
json.put("answer", answer);
json.put("remark", remark);
} catch (JSONException e) {
e.printStackTrace();
}
return json;
}
and in my other class:
JSONArray answers = new JSONArray();
ChecklistAnswer answer = new ChecklistAnswer(questions.get(id).id, 2, cb.isChecked(), text.getText().toString());
answers.put(answer.toJsonObject());
if i filled the array:
String js = answers.toString(1);
and that returns:
[
{
"answer": true,
"questionId": 1,
"remark": "",
"checklistId": 2
},
{
"answer": false,
"questionId": 4,
"remark": "teesxfgtfghyfj",
"checklistId": 2
},
{
"answer": true,
"questionId": 4,
"remark": "",
"checklistId": 2
},
{
"answer": true,
"questionId": 4,
"remark": "",
"checklistId": 2
},
{
"answer": true,
"questionId": 4,
"remark": "",
"checklistId": 2
},
{
"answer": true,
"questionId": 4,
"remark": "",
"checklistId": 2
},
{
"answer": true,
"questionId": 4,
"remark": "",
"checklistId": 2
}
]
thanks to @Selvin
Take a look at this tutorial. Also you can parse above json like :
JSONArray arr = new JSONArray(yourJSONresponse);
List<String> list = new ArrayList<String>();
for(int i = 0; i < arr.length(); i++){
list.add(arr.getJSONObject(i).getString("name"));
}
Simplest and correct code is:
public static String[] toStringArray(JSONArray array) {
if(array==null)
return new String[0];
String[] arr=new String[array.length()];
for(int i=0; i<arr.length; i++) {
arr[i]=array.optString(i);
}
return arr;
}
Using List<String> is not a good idea, as you know the length of the array.
Observe that it uses arr.length in for condition to avoid calling a method, i.e. array.length(), on each loop.
for your example:
{'profiles': [{'name':'john', 'age': 44}, {'name':'Alex','age':11}]}
you will have to do something of this effect:
JSONObject myjson = new JSONObject(the_json);
JSONArray the_json_array = myjson.getJSONArray("profiles");
this returns the array object.
Then iterating will be as follows:
int size = the_json_array.length();
ArrayList<JSONObject> arrays = new ArrayList<JSONObject>();
for (int i = 0; i < size; i++) {
JSONObject another_json_object = the_json_array.getJSONObject(i);
//Blah blah blah...
arrays.add(another_json_object);
}
//Finally
JSONObject[] jsons = new JSONObject[arrays.size()];
arrays.toArray(jsons);
//The end...
You will have to determine if the data is an array (simply checking that charAt(0) starts with [ character).
Hope this helps.
You can prefer quick-json parser to meet your requirement...
quick-json parser is very straight forward, flexible, very fast and customizable. Try this out
[quick-json parser] (https://code.google.com/p/quick-json/) - quick-json features -
Compliant with JSON specification (RFC4627)
High-Performance JSON parser
Supports Flexible/Configurable parsing approach
Configurable validation of key/value pairs of any JSON Heirarchy
Easy to use # Very Less foot print
Raises developer friendly and easy to trace exceptions
Pluggable Custom Validation support - Keys/Values can be validated by configuring custom validators as and when encountered
Validating and Non-Validating parser support
Support for two types of configuration (JSON/XML) for using quick-json validating parser
Require JDK 1.5 # No dependency on external libraries
Support for Json Generation through object serialization
Support for collection type selection during parsing process
For e.g.
JsonParserFactory factory=JsonParserFactory.getInstance();
JSONParser parser=factory.newJsonParser();
Map jsonMap=parser.parseJson(jsonString);
I finally got it:
ObjectMapper objectMapper = new ObjectMapper();
TypeFactory typeFactory = objectMapper.getTypeFactory();
List<SomeClass> someClassList = objectMapper.readValue(jsonString, typeFactory.constructCollectionType(List.class, SomeClass.class));
The other answer is correct, but for completeness, here are other ways:
List<SomeClass> list = mapper.readValue(jsonString, new TypeReference<List<SomeClass>>() { });
SomeClass[] array = mapper.readValue(jsonString, SomeClass[].class);
Issue is here:
JSONArray myjsonarray = myjson.toJSONArray(temparray);
Solution:
JSONArray myjsonarray = new JSONArray(myJSON);
// myJSON is String
Now here you are having JSONArray, iterate over it and prepare ArrayList of whatever types of you want.
here you get JSONArray so change
JSONArray myjsonarray = myjson.toJSONArray(temparray);
line as shown below
JSONArray jsonArray = new JSONArray(readlocationFeed);
and after
JSONArray jsonArray = new JSONArray(readlocationFeed);
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject explrObject = jsonArray.getJSONObject(i);
explrObject.getString("caption");
}
Using a stream you could convert it like so:
String s = "[\"A\",\"B\",\"C\",\"D\",\"E\"]";
String[] arr = Arrays.stream(s.substring(1, s.length()-1).split(","))
.map(e -> e.replaceAll("\"", ""))
.toArray(String[]::new);
You could also use a JSON library (which might be the prefered way). For example using Jackson:
String s = "[\"A\",\"B\",\"C\",\"D\",\"E\"]";
ObjectMapper mapper = new ObjectMapper();
String[] arr = mapper.readValue(s, String[].class);
ArrayList<String> jsonStringToArray(String jsonString) throws JSONException {
ArrayList<String> stringArray = new ArrayList<String>();
JSONArray jsonArray = new JSONArray(jsonString);
for (int i = 0; i < jsonArray.length(); i++) {
stringArray.add(jsonArray.getString(i));
}
return stringArray;
}