JsonUtils.java

/*
 * Copyright (C) 2016 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.android.utils;

import android.content.Context;
import android.content.res.Resources;

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

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class JsonUtils {

    public static JSONObject readFromRawFile(Context context, int rawFileResId)
            throws IOException, JSONException {
        InputStream stream = context.getResources().openRawResource(rawFileResId);
        BufferedReader reader = null;
        try {
            reader = new BufferedReader(new InputStreamReader(stream, "UTF-8"));
            StringBuilder stringBuilder = new StringBuilder();
            String input;
            while ((input = reader.readLine()) != null) {
                stringBuilder.append(input);
            }
            return new JSONObject(stringBuilder.toString());
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                }
            }
        }

    }

    public static String getString(JSONObject jsonObject, String key) throws JSONException {
        if (jsonObject != null && jsonObject.has(key)) {
            return jsonObject.getString(key);
        }

        return null;
    }

    public static int getInt(JSONObject jsonObject, String key) throws JSONException {
        if (jsonObject != null && jsonObject.has(key)) {
            return jsonObject.getInt(key);
        }

        return -1;
    }

    public static JSONArray getJsonArray(JSONObject jsonObject, String key) throws JSONException {
        if (jsonObject != null && jsonObject.has(key)) {
            return jsonObject.getJSONArray(key);
        }

        return null;
    }

    public static JSONObject getJsonObject(JSONObject jsonObject, String key) throws JSONException {
        if (jsonObject != null && jsonObject.has(key)) {
            return jsonObject.getJSONObject(key);
        }

        return null;
    }

    public static String readStringByResourceIdFromString(Context context,
                                                          String resourceIdString) {
        int resourceId = getResourceIdFromString(context, resourceIdString);
        if (resourceId != 0) {
            return context.getString(resourceId);
        }

        return null;
    }

    public static int getResourceIdFromString(Context context, String resourceIdString) {
        if (resourceIdString == null) {
            return 0;
        }

        if (resourceIdString.startsWith("@")) {
            resourceIdString = resourceIdString.substring(1);
        }

        String[] pair = resourceIdString.split("/");
        if (pair == null || pair.length != 2) {
            throw new IllegalArgumentException("Resource parameter is malformed: " +
                    resourceIdString);
        }

        Resources res = context.getResources();
        return res.getIdentifier(pair[1], pair[0], context.getPackageName());
    }

}