Java tutorial
/******************************************************************************* * Copyright 2013-2014 alladin-IT GmbH * * 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 at.alladin.rmbt.controlServer; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.text.MessageFormat; import java.util.Arrays; import java.util.List; import java.util.Locale; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import org.restlet.resource.Get; import org.restlet.resource.Post; import at.alladin.rmbt.shared.ResourceManager; public class NewsResource extends ServerResource { @Post("json") public String request(final String entity) { addAllowOrigin(); JSONObject request = null; final ErrorList errorList = new ErrorList(); final JSONObject answer = new JSONObject(); String answerString; System.out.println(MessageFormat.format(labels.getString("NEW_NEWS"), getIP())); if (entity != null && !entity.isEmpty()) // try parse the string to a JSON object try { request = new JSONObject(entity); String lang = request.optString("language"); // Load Language Files for Client final List<String> langs = Arrays .asList(settings.getString("RMBT_SUPPORTED_LANGUAGES").split(",\\s*")); if (langs.contains(lang)) { errorList.setLanguage(lang); labels = ResourceManager.getSysMsgBundle(new Locale(lang)); } else lang = settings.getString("RMBT_DEFAULT_LANGUAGE"); String sqlLang = lang; if (!sqlLang.equals("de")) sqlLang = "en"; if (conn != null) { final long lastNewsUid = request.optLong("lastNewsUid"); final String plattform = request.optString("plattform"); final int softwareVersionCode = request.optInt("softwareVersionCode", -1); String uuid = request.optString("uuid"); final JSONArray newsList = new JSONArray(); try { final PreparedStatement st = conn.prepareStatement("SELECT uid,title_" + sqlLang + " AS title, text_" + sqlLang + " AS text FROM news " + " WHERE" + " (uid > ? OR force = true)" + " AND active = true" + " AND (plattform IS NULL OR plattform = ?)" + " AND (max_software_version_code IS NULL OR ? <= max_software_version_code)" + " AND (min_software_version_code IS NULL OR ? >= min_software_version_code)" + " AND (uuid IS NULL OR uuid::TEXT = ?)" + //convert to text so that empty uuid-strings are tolerated " ORDER BY time ASC"); st.setLong(1, lastNewsUid); st.setString(2, plattform); st.setInt(3, softwareVersionCode); st.setInt(4, softwareVersionCode); st.setString(5, uuid); final ResultSet rs = st.executeQuery(); while (rs.next()) { final JSONObject jsonItem = new JSONObject(); jsonItem.put("uid", rs.getInt("uid")); jsonItem.put("title", rs.getString("title")); jsonItem.put("text", rs.getString("text")); newsList.put(jsonItem); } rs.close(); st.close(); } catch (final SQLException e) { e.printStackTrace(); errorList.addError("ERROR_DB_GET_NEWS_SQL"); } // } answer.put("news", newsList); } else errorList.addError("ERROR_DB_CONNECTION"); } catch (final JSONException e) { errorList.addError("ERROR_REQUEST_JSON"); System.out.println("Error parsing JSON Data " + e.toString()); } else errorList.addErrorString("Expected request is missing."); try { answer.putOpt("error", errorList.getList()); } catch (final JSONException e) { System.out.println("Error saving ErrorList: " + e.toString()); } answerString = answer.toString(); return answerString; } @Get("json") public String retrieve(final String entity) { return request(entity); } }