How to check if JSONArray Element is null

Question

I can\'t figure out how to determine is an element that lives inside a json array is null. To check if the jsonObject itself is null, you simply use:

jsonObj         


        

Answer 1

try JSONArray's method

public boolean isNull (int index)

In fact, it uses "null" string comparing to the content

JSONObject.NULL.equals(this.opt(index));

Answer 2

Try .isNull():

For your example:

if(!mapItem.isNull("date")) {
    //Value is not null
}

However, to answer the title of this question, "how to tell if a JSONArray element is null", use .equals()

So, to check if index 1 is null:

if (!jsonArray.get(1).equals(null)) {
    //jsonArray[1] is not null
}

Answer 3

I guess json passes null values as strings, so you can't check null as a java element. Instead treat the null value as a string as check this way:

if(!mapItem.getString("date").equals("null")) {
    //Value is not null
}

I have updated the code snippet in the original question to a working version.