Java tutorial
/** * UserServlet * Copyright 27.05.2015 by Michael Peter Christen, @0rb1t3r * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program in the file lgpl21.txt * If not, see <http://www.gnu.org/licenses/>. */ package org.loklak.api.server; import java.io.IOException; import java.io.PrintWriter; import java.util.ArrayList; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.loklak.harvester.TwitterAPI; import org.loklak.http.RemoteAccess; import twitter4j.TwitterException; import com.fasterxml.jackson.databind.ObjectMapper; public class UserServlet extends HttpServlet { private static final long serialVersionUID = 8578478303032749879L; @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { RemoteAccess.Post post = RemoteAccess.evaluate(request); // manage DoS if (post.isDoS_blackout()) { response.sendError(503, "your request frequency is too high"); return; } // parameters String callback = post.get("callback", ""); boolean jsonp = callback != null && callback.length() > 0; boolean minified = post.get("minified", false); String[] screen_names = post.get("screen_name", "").split(","); String followers = screen_names.length == 1 ? post.get("followers", "0") : "0"; String following = screen_names.length == 1 ? post.get("following", "0") : "0"; int maxFollowers = Integer.parseInt(followers); int maxFollowing = Integer.parseInt(following); List<Map<String, Object>> twitterUserEntries = new ArrayList<>(); for (String screen_name : screen_names) { try { Map<String, Object> twitterUserEntry = TwitterAPI.getUser(screen_name, false); if (twitterUserEntry != null) { TwitterAPI.enrichLocation(twitterUserEntry); twitterUserEntries.add(twitterUserEntry); } } catch (TwitterException e) { } } Map<String, Object> topology = null; try { topology = TwitterAPI.getNetwork(screen_names[0], maxFollowers, maxFollowing); } catch (TwitterException e) { } post.setResponse(response, "application/javascript"); // generate json Map<String, Object> m = new LinkedHashMap<>(); Map<String, Object> metadata = new LinkedHashMap<>(); metadata.put("client", post.getClientHost()); m.put("search_metadata", metadata); if (twitterUserEntries.size() == 1) m.put("user", twitterUserEntries.iterator().next()); if (twitterUserEntries.size() > 1) m.put("users", twitterUserEntries); if (topology != null) m.put("topology", topology); // write json response.setCharacterEncoding("UTF-8"); PrintWriter sos = response.getWriter(); if (jsonp) sos.print(callback + "("); sos.print((minified ? new ObjectMapper().writer() : new ObjectMapper().writerWithDefaultPrettyPrinter()) .writeValueAsString(m)); if (jsonp) sos.println(");"); sos.println(); sos.flush(); sos.close(); post.finalize(); } }