Java tutorial
/* * Copyright 2000-2018 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.server; import java.io.Serializable; import java.util.Date; import java.util.Locale; import java.util.TimeZone; import com.vaadin.shared.VBrowserDetails; /** * Class that provides information about the web browser the user is using. * Provides information such as browser name and version, screen resolution and * IP address. * * @author Vaadin Ltd. */ public class WebBrowser implements Serializable { private int screenHeight = -1; private int screenWidth = -1; private String browserApplication = null; private Locale locale; private String address; private boolean secureConnection; private int timezoneOffset = 0; private int rawTimezoneOffset = 0; private int dstSavings; private boolean dstInEffect; private String timeZoneId; private boolean touchDevice; private VBrowserDetails browserDetails; private long clientServerTimeDelta; /** * Gets the height of the screen in pixels. This is the full screen * resolution and not the height available for the application. * * @return the height of the screen in pixels. */ public int getScreenHeight() { return screenHeight; } /** * Gets the width of the screen in pixels. This is the full screen * resolution and not the width available for the application. * * @return the width of the screen in pixels. */ public int getScreenWidth() { return screenWidth; } /** * Get the browser user-agent string. * * @return The raw browser userAgent string */ public String getBrowserApplication() { return browserApplication; } /** * Gets the IP-address of the web browser. If the application is running * inside a portlet, this method will return null. * * @return IP-address in 1.12.123.123 -format */ public String getAddress() { return address; } /** Get the default locate of the browser. */ public Locale getLocale() { return locale; } /** Is the connection made using HTTPS? */ public boolean isSecureConnection() { return secureConnection; } /** * Tests whether the user is using Firefox. * * @return true if the user is using Firefox, false if the user is not using * Firefox or if no information on the browser is present */ public boolean isFirefox() { if (browserDetails == null) { return false; } return browserDetails.isFirefox(); } /** * Tests whether the user is using Internet Explorer. * * @return true if the user is using Internet Explorer, false if the user is * not using Internet Explorer or if no information on the browser * is present */ public boolean isIE() { if (browserDetails == null) { return false; } return browserDetails.isIE(); } /** * Tests whether the user is using Edge. * * @since 7.5.3 * @return true if the user is using Edge, false if the user is not using * Edge or if no information on the browser is present */ public boolean isEdge() { if (browserDetails == null) { return false; } return browserDetails.isEdge(); } /** * Tests whether the user is using Safari. Note that Chrome on iOS is not * detected as Safari but as Chrome although the underlying browser engine * is the same. * * @return true if the user is using Safari, false if the user is not using * Safari or if no information on the browser is present */ public boolean isSafari() { if (browserDetails == null) { return false; } return browserDetails.isSafari(); } /** * Tests whether the user is using Opera. * * @return true if the user is using Opera, false if the user is not using * Opera or if no information on the browser is present */ public boolean isOpera() { if (browserDetails == null) { return false; } return browserDetails.isOpera(); } /** * Tests whether the user is using Chrome. * * @return true if the user is using Chrome, false if the user is not using * Chrome or if no information on the browser is present */ public boolean isChrome() { if (browserDetails == null) { return false; } return browserDetails.isChrome(); } /** * Tests whether the user is using Chrome Frame. * * @return true if the user is using Chrome Frame, false if the user is not * using Chrome or if no information on the browser is present */ public boolean isChromeFrame() { if (browserDetails == null) { return false; } return browserDetails.isChromeFrame(); } /** * Tests whether the user's browser is Chrome Frame capable. * * @return true if the user can use Chrome Frame, false if the user can not * or if no information on the browser is present */ public boolean isChromeFrameCapable() { if (browserDetails == null) { return false; } return browserDetails.isChromeFrameCapable(); } /** * Gets the major version of the browser the user is using. * * <p> * Note that Internet Explorer in IE7 compatibility mode might return 8 in * some cases even though it should return 7. * </p> * * @return The major version of the browser or -1 if not known. */ public int getBrowserMajorVersion() { if (browserDetails == null) { return -1; } return browserDetails.getBrowserMajorVersion(); } /** * Gets the minor version of the browser the user is using. * * @see #getBrowserMajorVersion() * * @return The minor version of the browser or -1 if not known. */ public int getBrowserMinorVersion() { if (browserDetails == null) { return -1; } return browserDetails.getBrowserMinorVersion(); } /** * Gets the complete browser version as string. The version is given by the * browser through the user agent string and usually consists of * dot-separated numbers. Note that the string may contain characters other * than dots and digits. * * @return the complete browser version or {@code null} if unknown * @since 8.4 */ public String getBrowserVersion() { return browserDetails != null ? browserDetails.getBrowserVersion() : null; } /** * Tests whether the user is using Linux. * * @return true if the user is using Linux, false if the user is not using * Linux or if no information on the browser is present */ public boolean isLinux() { return browserDetails.isLinux(); } /** * Tests whether the user is using Mac OS X. * * @return true if the user is using Mac OS X, false if the user is not * using Mac OS X or if no information on the browser is present */ public boolean isMacOSX() { return browserDetails.isMacOSX(); } /** * Tests whether the user is using Windows. * * @return true if the user is using Windows, false if the user is not using * Windows or if no information on the browser is present */ public boolean isWindows() { return browserDetails.isWindows(); } /** * Tests whether the user is using Windows Phone. * * @return true if the user is using Windows Phone, false if the user is not * using Windows Phone or if no information on the browser is * present * @since 7.3.2 */ public boolean isWindowsPhone() { return browserDetails.isWindowsPhone(); } /** * Tests if the browser is run on Android. * * @return true if run on Android false if the user is not using Android or * if no information on the browser is present */ public boolean isAndroid() { return browserDetails.isAndroid(); } /** * Tests if the browser is run in iOS. * * @return true if run in iOS false if the user is not using iOS or if no * information on the browser is present */ public boolean isIOS() { return browserDetails.isIOS(); } /** * Tests if the browser is run on IPhone. * * @return true if run on IPhone false if the user is not using IPhone or if * no information on the browser is present * @since 7.3.3 */ public boolean isIPhone() { return browserDetails.isIPhone(); } /** * Tests if the browser is run on IPad. * * @return true if run on IPad false if the user is not using IPad or if no * information on the browser is present * @since 7.3.3 */ public boolean isIPad() { return browserDetails.isIPad(); } /** * Tests if the browser is run on ChromeOS (e.g. a Chromebook). * * @return true if run on ChromeOS false if the user is not using ChromeOS * or if no information on the browser is present * @since 8.1.1 */ public boolean isChromeOS() { return browserDetails.isChromeOS(); } /** * Returns the browser-reported TimeZone offset in milliseconds from GMT. * This includes possible daylight saving adjustments, to figure out which * TimeZone the user actually might be in, see * {@link #getRawTimezoneOffset()}. * * @see WebBrowser#getRawTimezoneOffset() * @return timezone offset in milliseconds, 0 if not available */ public int getTimezoneOffset() { return timezoneOffset; } /** * Returns the TimeZone Id (like "Europe/Helsinki") provided by the browser * (if the browser supports this feature). * * @return the TimeZone Id if provided by the browser, null otherwise. * @see <a href= * "https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat/resolvedOptions">Intl.DateTimeFormat.prototype.resolvedOptions()</a> * @since 8.2 */ public String getTimeZoneId() { return timeZoneId; } /** * Returns the browser-reported TimeZone offset in milliseconds from GMT * ignoring possible daylight saving adjustments that may be in effect in * the browser. * <p> * You can use this to figure out which TimeZones the user could actually be * in by calling {@link TimeZone#getAvailableIDs(int)}. * </p> * <p> * If {@link #getRawTimezoneOffset()} and {@link #getTimezoneOffset()} * returns the same value, the browser is either in a zone that does not * currently have daylight saving time, or in a zone that never has daylight * saving time. * </p> * * @return timezone offset in milliseconds excluding DST, 0 if not available */ public int getRawTimezoneOffset() { return rawTimezoneOffset; } /** * Returns the offset in milliseconds between the browser's GMT TimeZone and * DST. * * @return the number of milliseconds that the TimeZone shifts when DST is * in effect */ public int getDSTSavings() { return dstSavings; } /** * Returns whether daylight saving time (DST) is currently in effect in the * region of the browser or not. * * @return true if the browser resides at a location that currently is in * DST */ public boolean isDSTInEffect() { return dstInEffect; } /** * Returns the current date and time of the browser. This will not be * entirely accurate due to varying network latencies, but should provide a * close-enough value for most cases. Also note that the returned Date * object uses servers default time zone, not the clients. * <p> * To get the actual date and time shown in the end users computer, you can * do something like: * * <pre> * WebBrowser browser = ...; * SimpleTimeZone timeZone = new SimpleTimeZone(browser.getTimezoneOffset(), "Fake client time zone"); * DateFormat format = DateFormat.getDateTimeInstance(); * format.setTimeZone(timeZone); * myLabel.setValue(format.format(browser.getCurrentDate())); * </pre> * * @return the current date and time of the browser. * @see #isDSTInEffect() * @see #getDSTSavings() * @see #getTimezoneOffset() */ public Date getCurrentDate() { return new Date(new Date().getTime() + clientServerTimeDelta); } /** * @return true if the browser is detected to support touch events */ public boolean isTouchDevice() { return touchDevice; } /** * For internal use by VaadinServlet/VaadinPortlet only. Updates all * properties in the class according to the given information. * * @param sw * Screen width * @param sh * Screen height * @param tzo * TimeZone offset in minutes from GMT * @param rtzo * raw TimeZone offset in minutes from GMT (w/o DST adjustment) * @param dstSavings * the difference between the raw TimeZone and DST in minutes * @param dstInEffect * is DST currently active in the region or not? * @param curDate * the current date in milliseconds since the epoch * @param touchDevice */ void updateClientSideDetails(String sw, String sh, String tzo, String rtzo, String dstSavings, String dstInEffect, String tzId, String curDate, boolean touchDevice) { if (sw != null) { try { screenHeight = Integer.parseInt(sh); screenWidth = Integer.parseInt(sw); } catch (final NumberFormatException e) { screenHeight = screenWidth = -1; } } if (tzo != null) { try { // browser->java conversion: min->ms, reverse sign timezoneOffset = -Integer.parseInt(tzo) * 60 * 1000; } catch (final NumberFormatException e) { timezoneOffset = 0; // default gmt+0 } } if (rtzo != null) { try { // browser->java conversion: min->ms, reverse sign rawTimezoneOffset = -Integer.parseInt(rtzo) * 60 * 1000; } catch (final NumberFormatException e) { rawTimezoneOffset = 0; // default gmt+0 } } if (dstSavings != null) { try { // browser->java conversion: min->ms this.dstSavings = Integer.parseInt(dstSavings) * 60 * 1000; } catch (final NumberFormatException e) { this.dstSavings = 0; // default no savings } } if (dstInEffect != null) { this.dstInEffect = Boolean.parseBoolean(dstInEffect); } if (tzId == null || "undefined".equals(tzId)) { timeZoneId = null; } else { timeZoneId = tzId; } if (curDate != null) { try { long curTime = Long.parseLong(curDate); clientServerTimeDelta = curTime - new Date().getTime(); } catch (final NumberFormatException e) { clientServerTimeDelta = 0; } } this.touchDevice = touchDevice; } /** * For internal use by VaadinServlet/VaadinPortlet only. Updates all * properties in the class according to the given information. * * @param request * the Vaadin request to read the information from */ public void updateRequestDetails(VaadinRequest request) { locale = request.getLocale(); address = request.getRemoteAddr(); secureConnection = request.isSecure(); // Headers are case insensitive according to the specification but are // case sensitive in Weblogic portal... String agent = request.getHeader("User-Agent"); if (agent != null) { browserApplication = agent; browserDetails = new VBrowserDetails(agent); } if (request.getParameter("v-sw") != null) { updateClientSideDetails(request.getParameter("v-sw"), request.getParameter("v-sh"), request.getParameter("v-tzo"), request.getParameter("v-rtzo"), request.getParameter("v-dstd"), request.getParameter("v-dston"), request.getParameter("v-tzid"), request.getParameter("v-curdate"), request.getParameter("v-td") != null); } } /** * Checks if the browser is so old that it simply won't work with a Vaadin * application. Can be used to redirect to an alternative page, show * alternative content or similar. * * When this method returns true chances are very high that the browser * won't work and it does not make sense to direct the user to the Vaadin * application. * * @return true if the browser won't work, false if not the browser is * supported or might work */ public boolean isTooOldToFunctionProperly() { if (browserDetails == null) { // Don't know, so assume it will work return false; } return browserDetails.isTooOldToFunctionProperly(); } /** * Checks if the browser supports ECMAScript 6, based on the user agent. * * @return <code>true</code> if the browser supports ES6, <code>false</code> * otherwise. * @since 8.1 */ public boolean isEs6Supported() { if (browserDetails == null) { // Don't know, so assume no return false; } return browserDetails.isEs6Supported(); } }