How can I control a empty JsonArray, if string is " [ ] " [duplicate]

Question

my json string is

String RESPONSE = "  { "Table": [] }  ";

and I use

 JSONObject jsonObj = new JSONObject(RESPONSE);
 JSONArray contacts = jsonObj.getJSONArray("Table");

Therefore, contacts = [] I mean empty. How can I control that array is empty. After this controller I use this command

JSONObject c = contacts.getJSONObject(0);

Of course is not empty :)

What do you mean "Of course is not empty"? Did you put something in it after your previous code where you obtained a clearly empty array? — azurefrog
– azurefrog, Commented Mar 13, 2017 at 17:57

Veneet Reddy · Accepted Answer · 2017-03-13 17:58:39Z

1

You can use length function:

JSONObject jsonObj = new JSONObject(RESPONSE);
JSONArray contacts = jsonObj.getJSONArray("Table");
if(contacts.length() > 0 ) {
    JSONObject c = contacts.getJSONObject(0);
}

answered Mar 13, 2017 at 17:58

Veneet Reddy

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2 Comments

Sefa Taşcan Over a year ago

I've tried. Not working

Veneet Reddy Over a year ago

what was happening, were you getting some error?

Dec · Accepted Answer · 2017-03-13 18:07:23Z

1

You could use the isNull() function.

JSONObject jsonObj = new JSONObject(RESPONSE);
JSONArray contacts = jsonObj.getJSONArray("Table");
if(!contacts.isNull(0)) {
   JSONObject c = contacts.getJSONObject(0);
}

edited Mar 13, 2017 at 18:07

answered Mar 13, 2017 at 18:01

Dec

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10 Comments

Sefa Taşcan Over a year ago

No such function

Dec Over a year ago

Correct. Edited to show isNull.

Sefa Taşcan Over a year ago

No, Not working

Sefa Taşcan Over a year ago

contacts = " [ ] " ;

Dec Over a year ago

Have I miss understood the question? What do you mean by not working? are you saying contacts[0] is empty yet the if statement is still executing?

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