java - 如何从java中的JSONObject获取所有键/子键？

Question

这是我的 JSONObject :

{
    "per_page": 3,
    "total": 12,
    "data": [{
            "color": "#98B2D1",
            "year": 2000,
            "name": "cerulean",
            "id": 1,
            "pantone_value": "15-4020"
        }, {
            "color": "#C74375",
            "year": 2001,
            "name": "fuchsia rose",
            "id": 2,
            "pantone_value": "17-2031"
        }
    ],
    "page": 1,
    "total_pages": 4
}

从中我应该得到所有的键，包括per_page，total，data，color，年份、pantone_value、名称、页和total_pages

如果我使用 JSONObject.names() 或 JSONObject.keySet() 。我只得到最外面的键

Answer 1

package com.samples;

import java.util.Iterator;

import gvjava.org.json.JSONArray;
import gvjava.org.json.JSONException;
import gvjava.org.json.JSONObject;

public class JSONObjectSample {

    public static void main (String [] args) {
        String jsonString = new String("{\"per_page\": 3,\"total\": 12,\"data\": [{\"color\": \"#98B2D1\",\"year\": 2000,\"name\": \"cerulean\",\"id\": 1,\"pantone_value\": \"15-4020\" }, {\"color\": \"#C74375\",\"year\": 2001,\"name\": \"fuchsia rose\",\"id\": 2,\"pantone_value\": \"17-2031\" }], \"page\": 1,\"total_pages\": 4 }\r\n");
        try {
            JSONObject jsonObject = new JSONObject(jsonString);
            Iterator<String> keys = jsonObject.keys();
            while(keys.hasNext()) {
                String key = keys.next();
                System.out.println(key);
                if(jsonObject.get(key) instanceof JSONArray) {
                    JSONArray array = (JSONArray) jsonObject.get(key);
                    JSONObject object = (JSONObject) array.get(0);
                    Iterator<String> innerKeys = object.keys();
                    while(innerKeys.hasNext()) {
                        String innerKey = innerKeys.next();
                        System.out.println(innerKey);
                    }
                }
            }

        } catch (JSONException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}