keys() is undefined for the type JSONObject

Question

Why do i get this error when i'm trying to get the keys of JSONObject ?
its clearly in the API

And I'm importing the correct library :

import org.json.simple.JSONArray;
import org.json.simple.JSONObject;

I saw an example of usage and it is working for them .
this is part of my code where i get the error :

JSONArray pObject = (JSONArray) srcClaims.get(i);
for (int j=0; j < pObject.size() ; j++) {
    JSONObject mainsnak = (JSONObject) pObject.get(j);
    mainsnak.keys();

And i forgot to mention the libray i'm using json-simple-1.1.1.jar.

Is the title of your question the *exact* error message? Are you sure you don't have another class called `JSONObject`? If you hover over `JSONObject` in the IDE, what fully-qualified name does it show? — Jon Skeet, Nov 21 '15 at 19:43
You're refering to a documentation of another library. It has defined JSONObject in the package `org.json.JSONObject`, you're importing from `org.json.simple`. — try-catch-finally, Nov 21 '15 at 19:45
yes the exact message, and when i hover the JSONObject i get org.json.simple.JSONObject — Epsilon, Nov 21 '15 at 19:45

score 6 · Accepted Answer · answered Nov 21 '15 at 19:46

6

You're looking at the documentation for the wrong library. In json-simple, JSONObject extends HashMap, so you should use keySet()... or change to use the json.org library instead.

answered Nov 21 '15 at 19:46

Jon Skeet

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thanks i downloaded the org.json-20120521.jar and it works – Epsilon Nov 21 '15 at 19:52

keys() is undefined for the type JSONObject

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