Java tutorial
/** This file is part of Meet-Hub-Hannover. Meet-Hub-Hannover is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. Meet-Hub-Hannover 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 General Public License for more details. You should have received a copy of the GNU General Public License along with Meet-Hub-Hannover. If not, see <http://www.gnu.org/licenses/>. */ package de.meethub.adapters.eventbrite; import java.io.IOException; import java.text.ParseException; import java.util.Date; import java.util.GregorianCalendar; import java.util.List; import java.util.TimeZone; import java.util.regex.Matcher; import java.util.regex.Pattern; import javax.servlet.ServletConfig; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import net.fortuna.ical4j.data.CalendarOutputter; import net.fortuna.ical4j.model.Calendar; import net.fortuna.ical4j.model.ValidationException; import net.fortuna.ical4j.model.component.VEvent; import net.fortuna.ical4j.model.property.CalScale; import net.fortuna.ical4j.model.property.ProdId; import net.fortuna.ical4j.model.property.Uid; import net.fortuna.ical4j.model.property.Version; import org.openqa.selenium.By; import org.openqa.selenium.WebDriver; import org.openqa.selenium.WebElement; import org.openqa.selenium.htmlunit.HtmlUnitDriver; import org.openqa.selenium.support.ui.ExpectedConditions; import org.openqa.selenium.support.ui.WebDriverWait; public class EventbriteAdapterServlet extends HttpServlet { private static final long serialVersionUID = -279955077272627865L; private String baseUrl; @Override public void init(final ServletConfig config) throws ServletException { super.init(config); this.baseUrl = config.getInitParameter("base-url"); } @Override protected void doGet(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException { final WebDriver d = new HtmlUnitDriver(); try { d.get(this.baseUrl); new WebDriverWait(d, 10) .until(ExpectedConditions.presenceOfElementLocated(By.className("js-event-list-container"))); final List<WebElement> eventElements = d.findElements(By.className("event-card__description")); final Calendar calendar = this.convertToCalendar(eventElements); final CalendarOutputter outputter = new CalendarOutputter(); response.setContentType("text/calendar;charset=UTF-8"); outputter.output(calendar, response.getWriter()); } catch (final ValidationException | ParseException e) { throw new ServletException(e); } finally { d.close(); } } private Calendar convertToCalendar(final List<WebElement> eventElements) throws ParseException { final Calendar ret = new Calendar(); ret.getProperties().add(new ProdId("-//Meet-Hub Hannover//hjs//DE")); ret.getProperties().add(Version.VERSION_2_0); ret.getProperties().add(CalScale.GREGORIAN); for (final WebElement eventElement : eventElements) { final VEvent event = this.convertEvent(eventElement); ret.getComponents().add(event); } return ret; } private VEvent convertEvent(final WebElement eventElement) throws ParseException { final String title = eventElement.findElement(By.className("event-card__header")).getText(); final String dateText = eventElement.findElement(By.className("event-card__details")).getText(); final Date parsedDate = parseDate(dateText); final VEvent event = new VEvent(new net.fortuna.ical4j.model.DateTime(parsedDate), title); event.getProperties() .add(new Uid("mhe" + Integer.toHexString(this.baseUrl.hashCode()) + parsedDate.getTime())); return event; } private static Date parseDate(final String dateElementContent) throws ParseException { final Pattern p1 = Pattern.compile("([A-Za-z]+) ([0-9]+), ([0-9]+) ([0-9]+):([0-9]+) (PM|AM).*"); Matcher m; m = p1.matcher(dateElementContent); if (m.matches()) { final int month = convertMonth(m.group(1).toLowerCase()); final int day = Integer.parseInt(m.group(2)); final int year = Integer.parseInt(m.group(3)); final int hour = Integer.parseInt(m.group(4)); final int minute = Integer.parseInt(m.group(5)); final boolean pm = m.group(6).equalsIgnoreCase("PM"); final GregorianCalendar currentDate = new GregorianCalendar(); currentDate.setTimeZone(TimeZone.getTimeZone("Europe/Berlin")); currentDate.set(year, month - 1, day, hour + (pm ? 12 : 0), minute, 0); return currentDate.getTime(); } final Pattern p2 = Pattern.compile("[A-Za-z]+, ([A-Za-z]+) ([0-9]+) ([0-9]+):([0-9]+) (PM|AM).*"); m = p2.matcher(dateElementContent); if (m.matches()) { final int month = convertMonth(m.group(1).toLowerCase()); final int day = Integer.parseInt(m.group(2)); final int year = new GregorianCalendar().get(GregorianCalendar.YEAR); final int hour = Integer.parseInt(m.group(3)); final int minute = Integer.parseInt(m.group(4)); final boolean pm = m.group(5).equalsIgnoreCase("PM"); final GregorianCalendar currentDate = new GregorianCalendar(); currentDate.setTimeZone(TimeZone.getTimeZone("Europe/Berlin")); currentDate.set(year, month - 1, day, hour + (pm ? 12 : 0), minute, 0); return currentDate.getTime(); } throw new ParseException("date not in expected format: " + dateElementContent, 0); } private static int convertMonth(final String monthName) throws ParseException { if (monthName.equals("jan")) { return 1; } else if (monthName.equals("feb")) { return 2; } else if (monthName.equals("mar")) { return 3; } else if (monthName.equals("apr")) { return 4; } else if (monthName.equals("may")) { return 5; } else if (monthName.equals("jun")) { return 6; } else if (monthName.equals("jul")) { return 7; } else if (monthName.equals("aug")) { return 8; } else if (monthName.equals("sep")) { return 9; } else if (monthName.equals("oct")) { return 10; } else if (monthName.equals("nov")) { return 11; } else if (monthName.equals("dec")) { return 12; } else { throw new ParseException("invalid month name: " + monthName, 0); } } }