Java tutorial
/* Copyright (c) 2011 Ivan Ivanenko <ivan.ivanenko@gmail.com> * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package com.foobnix.api.vkontakte; import java.util.ArrayList; import java.util.List; import com.foobnix.commons.string.StringUtils; import com.foobnix.exception.VkErrorException; import com.foobnix.util.LOG; import com.google.gson.Gson; import com.google.gson.JsonArray; import com.google.gson.JsonElement; import com.google.gson.JsonParser; public class VkGsonResponse { public static <T> List<T> toModels(String json, Class<T> clazz) throws VkErrorException { return toModels(json, clazz, 1); } public static <T> List<T> toModels(String json, Class<T> clazz, int startIndex) throws VkErrorException { List<T> result = new ArrayList<T>(); if (StringUtils.isEmpty(json) || json.trim().equalsIgnoreCase("{\"response\":{}}")) { LOG.d("Recive an empty json", json); return result; } if (json.trim().startsWith("{\"error\":")) { throw new VkErrorException(json); } Gson gson = new Gson(); JsonParser parser = new JsonParser(); JsonArray array = parser.parse(json).getAsJsonObject().getAsJsonArray("response"); for (int i = startIndex; i < array.size(); i++) { JsonElement next = array.get(i); T fromJson = gson.fromJson(next, clazz); result.add(fromJson); } return result; } }