Java tutorial
/* * Copyright 2000-2016 Vaadin Ltd. * * 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.vaadin.tools; import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URL; import java.net.URLConnection; import java.util.concurrent.Callable; import java.util.concurrent.FutureTask; import java.util.logging.Logger; import java.util.prefs.Preferences; import org.apache.commons.io.IOUtils; import com.google.gwt.dev.shell.CheckForUpdates; import com.vaadin.shared.Version; public class ReportUsage { public static final String ANONYMOUS_ID = loadFirstLaunch(); // for compatibility with old checks private static final String USER_AGENT_BASE = "GWT Freshness Checker"; private static final String COMPILER = "Compiler"; //$NON-NLS-1$ private static final String E_QPARAM = "&e="; //$NON-NLS-1$ private static final String R_QPARAM = "&r=unknown"; //$NON-NLS-1$ private static final String ID_QPARAM = "&id="; //$NON-NLS-1$ private static final String V_QPARAM = "?v="; //$NON-NLS-1$ private static final String USER_AGENT = "User-Agent"; //$NON-NLS-1$ // Use the GWT Freshness checker URL to store usage reports. private static final String QUERY_URL = "https://tools.vaadin.com/version/currentversion.xml"; //$NON-NLS-1$ // Preferences keys private static final String FIRST_LAUNCH = "firstLaunch"; //$NON-NLS-1$ private static final String LAST_PING = "lastPing"; public static final long ONE_DAY = 24 * 60 * 60 * 1000; // for testing only public static void main(String[] args) { report(); } public static FutureTask<Void> checkForUpdatesInBackgroundThread() { FutureTask<Void> task = new FutureTask<>(new Callable<Void>() { @Override public Void call() throws Exception { ReportUsage.report(); return null; } }); Thread checkerThread = new Thread(task, "Vaadin Update Checker"); checkerThread.setDaemon(true); checkerThread.start(); return task; } public static void report() { long currentTimeMillis = System.currentTimeMillis(); Preferences prefs = Preferences.userNodeForPackage(ReportUsage.class); String lastPing = prefs.get(LAST_PING, "0"); if (lastPing != null) { try { long lastPingTime = Long.parseLong(lastPing); if (currentTimeMillis < lastPingTime + ONE_DAY) { return; } } catch (NumberFormatException e) { // error parsing last ping time, ignore and ping } } StringBuilder url = new StringBuilder(QUERY_URL); url.append(V_QPARAM); url.append(Version.getFullVersion()); url.append(ID_QPARAM); url.append(ANONYMOUS_ID).append(R_QPARAM); // TODO add more relevant entry point if feasible String entryPoint = COMPILER; if (entryPoint != null) { url.append(E_QPARAM).append(entryPoint); } doHttpGet(makeUserAgent(), url.toString()); prefs.put(LAST_PING, String.valueOf(currentTimeMillis)); } private static void doHttpGet(String userAgent, String url) { Throwable caught; InputStream is = null; try { URL urlToGet = new URL(url); URLConnection conn = urlToGet.openConnection(); conn.setRequestProperty(USER_AGENT, userAgent); is = conn.getInputStream(); // TODO use the results IOUtils.toByteArray(is); return; } catch (MalformedURLException e) { caught = e; } catch (IOException e) { caught = e; } finally { IOUtils.closeQuietly(is); } Logger.getLogger(ReportUsage.class.getName()) .fine("Caught an exception while executing HTTP query: " + caught.getMessage()); } private static String makeUserAgent() { String userAgent = USER_AGENT_BASE; StringBuilder extra = new StringBuilder(); appendUserAgentProperty(extra, "java.vendor"); appendUserAgentProperty(extra, "java.version"); appendUserAgentProperty(extra, "os.arch"); appendUserAgentProperty(extra, "os.name"); appendUserAgentProperty(extra, "os.version"); if (extra.length() > 0) { userAgent += " (" + extra.toString() + ")"; } return userAgent.toString(); } private static void appendUserAgentProperty(StringBuilder sb, String propName) { String propValue = System.getProperty(propName); if (propValue != null) { if (sb.length() > 0) { sb.append(';').append(' '); } sb.append(propName); sb.append('='); sb.append(propValue); } } private static String loadFirstLaunch() { Preferences prefs = Preferences.userNodeForPackage(CheckForUpdates.class); String firstLaunch = prefs.get(FIRST_LAUNCH, null); if (firstLaunch == null) { long currentTimeMillis = System.currentTimeMillis(); firstLaunch = Long.toHexString(currentTimeMillis); prefs.put(FIRST_LAUNCH, firstLaunch); } return firstLaunch; } }