json - How to remove JSONArray element using Java

Question

My JsonArray is

[{
"Id": null,
"Name": "One New task",
"StartDate": "2010-02-03T05:30:00",
"EndDate": "2010-02-04T05:30:00",
"Duration": 1,
"DurationUnit": "d",
"PercentDone": 0,
"ManuallyScheduled": false,
"Priority": 1,
"parentId": 8,
"index": 0,
"depth": 3,
"checked": null },{
"Id": null,
"Name": "New task",
"StartDate": "2010-02-04T05:30:00",
"EndDate": "2010-02-04T05:30:00",
"Duration": 0,
"DurationUnit": "d",
"PercentDone": 0,
"ManuallyScheduled": false,
"Priority": 1,
"parentId": 8,
"index": 1,
"depth": 3,
"checked": null }]

Now from this JsonArray I want to remove Id, ManuallyScheduled, checked,

I tried using jsonArray.remove(1) and also jsonArray.discard("Id") in JAVA. but nothing happens. what am I doing wrong to remove array items?

I am using JAVA as my technology.

Answer 1

What you have there is an array of objects. Therefore you'll have to loop through the array and remove the necessary data from each object, e.g.

for (int i = 0, len = jsonArr.length(); i < len; i++) {
    JSONObject obj = jsonArr.getJSONObject(i);
    // Do your removals
    obj.remove("id");
    // etc.
}

I've assumed you're using org.json.JSONObject and org.json.JSONArray here, but the principal remains the same whatever JSON processing library you're using.

If you wanted to convert something like [{"id":215},{"id":216}] to [215,216] you could so something like:

JSONArray intArr = new JSONArray();
for (int i = 0, len = objArr.length(); i < len; i++) {
    intArr.put(objArr.getJSONObject(i).getInt("id"));
}