Java tutorial
/* * Copyright 2013 2015 Ricki Hirner (bitfire web engineering). * All rights reserved. This program and the accompanying materials * are made available under the terms of the GNU Public License v3.0 * which accompanies this distribution, and is available at * http://www.gnu.org/licenses/gpl.html */ package at.bitfire.davdroid.syncadapter; import android.accounts.Account; import android.content.Context; import android.content.SyncResult; import android.os.Bundle; import org.apache.commons.codec.Charsets; import org.apache.commons.lang3.StringUtils; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.nio.charset.Charset; import java.util.Calendar; import java.util.Date; import java.util.HashMap; import java.util.LinkedList; import java.util.List; import java.util.logging.Level; import at.bitfire.dav4android.DavCalendar; import at.bitfire.dav4android.DavResource; import at.bitfire.dav4android.exception.DavException; import at.bitfire.dav4android.exception.HttpException; import at.bitfire.dav4android.property.CalendarData; import at.bitfire.dav4android.property.GetCTag; import at.bitfire.dav4android.property.GetContentType; import at.bitfire.dav4android.property.GetETag; import at.bitfire.davdroid.AccountSettings; import at.bitfire.davdroid.App; import at.bitfire.davdroid.ArrayUtils; import at.bitfire.davdroid.Constants; import at.bitfire.davdroid.InvalidAccountException; import at.bitfire.davdroid.R; import at.bitfire.davdroid.resource.LocalCalendar; import at.bitfire.davdroid.resource.LocalEvent; import at.bitfire.davdroid.resource.LocalResource; import at.bitfire.ical4android.CalendarStorageException; import at.bitfire.ical4android.Event; import at.bitfire.ical4android.InvalidCalendarException; import at.bitfire.vcard4android.ContactsStorageException; import lombok.Cleanup; import okhttp3.HttpUrl; import okhttp3.MediaType; import okhttp3.RequestBody; import okhttp3.ResponseBody; /** * Synchronization manager for CalDAV collections; handles events ({@code VEVENT}). */ public class CalendarSyncManager extends SyncManager { protected static final int MAX_MULTIGET = 20; public CalendarSyncManager(Context context, Account account, AccountSettings settings, Bundle extras, String authority, SyncResult result, LocalCalendar calendar) throws InvalidAccountException { super(context, account, settings, extras, authority, result, "calendar/" + calendar.getId()); localCollection = calendar; } @Override protected int notificationId() { return Constants.NOTIFICATION_CALENDAR_SYNC; } @Override protected String getSyncErrorTitle() { return context.getString(R.string.sync_error_calendar, account.name); } @Override protected void prepare() { collectionURL = HttpUrl.parse(localCalendar().getName()); davCollection = new DavCalendar(httpClient, collectionURL); } @Override protected void queryCapabilities() throws DavException, IOException, HttpException { davCollection.propfind(0, GetCTag.NAME); } @Override protected void prepareDirty() throws CalendarStorageException, ContactsStorageException { super.prepareDirty(); localCalendar().processDirtyExceptions(); } @Override protected RequestBody prepareUpload(LocalResource resource) throws IOException, CalendarStorageException { LocalEvent local = (LocalEvent) resource; App.log.log(Level.FINE, "Preparing upload of event " + local.getFileName(), local.getEvent()); ByteArrayOutputStream os = new ByteArrayOutputStream(); local.getEvent().write(os); return RequestBody.create(DavCalendar.MIME_ICALENDAR, os.toByteArray()); } @Override protected void listRemote() throws IOException, HttpException, DavException { // calculate time range limits Date limitStart = null; Integer pastDays = settings.getTimeRangePastDays(); if (pastDays != null) { Calendar calendar = Calendar.getInstance(); calendar.add(Calendar.DAY_OF_MONTH, -pastDays); limitStart = calendar.getTime(); } // fetch list of remote VEVENTs and build hash table to index file name davCalendar().calendarQuery("VEVENT", limitStart, null); remoteResources = new HashMap<>(davCollection.members.size()); for (DavResource iCal : davCollection.members) { String fileName = iCal.fileName(); App.log.fine("Found remote VEVENT: " + fileName); remoteResources.put(fileName, iCal); } } @Override protected void downloadRemote() throws IOException, HttpException, DavException, CalendarStorageException { App.log.info("Downloading " + toDownload.size() + " events (" + MAX_MULTIGET + " at once)"); // download new/updated iCalendars from server for (DavResource[] bunch : ArrayUtils.partition(toDownload.toArray(new DavResource[toDownload.size()]), MAX_MULTIGET)) { if (Thread.interrupted()) return; App.log.info("Downloading " + StringUtils.join(bunch, ", ")); if (bunch.length == 1) { // only one contact, use GET DavResource remote = bunch[0]; ResponseBody body = remote.get("text/calendar"); // CalDAV servers MUST return ETag on GET [https://tools.ietf.org/html/rfc4791#section-5.3.4] GetETag eTag = (GetETag) remote.properties.get(GetETag.NAME); if (eTag == null || StringUtils.isEmpty(eTag.eTag)) throw new DavException("Received CalDAV GET response without ETag for " + remote.location); Charset charset = Charsets.UTF_8; MediaType contentType = body.contentType(); if (contentType != null) charset = contentType.charset(Charsets.UTF_8); @Cleanup InputStream stream = body.byteStream(); processVEvent(remote.fileName(), eTag.eTag, stream, charset); } else { // multiple contacts, use multi-get List<HttpUrl> urls = new LinkedList<>(); for (DavResource remote : bunch) urls.add(remote.location); davCalendar().multiget(urls.toArray(new HttpUrl[urls.size()])); // process multiget results for (DavResource remote : davCollection.members) { String eTag; GetETag getETag = (GetETag) remote.properties.get(GetETag.NAME); if (getETag != null) eTag = getETag.eTag; else throw new DavException("Received multi-get response without ETag"); Charset charset = Charsets.UTF_8; GetContentType getContentType = (GetContentType) remote.properties.get(GetContentType.NAME); if (getContentType != null && getContentType.type != null) { MediaType type = MediaType.parse(getContentType.type); if (type != null) charset = type.charset(Charsets.UTF_8); } CalendarData calendarData = (CalendarData) remote.properties.get(CalendarData.NAME); if (calendarData == null || calendarData.iCalendar == null) throw new DavException("Received multi-get response without address data"); @Cleanup InputStream stream = new ByteArrayInputStream(calendarData.iCalendar.getBytes()); processVEvent(remote.fileName(), eTag, stream, charset); } } } } // helpers private LocalCalendar localCalendar() { return ((LocalCalendar) localCollection); } private DavCalendar davCalendar() { return (DavCalendar) davCollection; } private void processVEvent(String fileName, String eTag, InputStream stream, Charset charset) throws IOException, CalendarStorageException { Event[] events; try { events = Event.fromStream(stream, charset); } catch (InvalidCalendarException e) { App.log.log(Level.SEVERE, "Received invalid iCalendar, ignoring", e); return; } if (events.length == 1) { Event newData = events[0]; // delete local event, if it exists LocalEvent localEvent = (LocalEvent) localResources.get(fileName); if (localEvent != null) { App.log.info("Updating " + fileName + " in local calendar"); localEvent.setETag(eTag); localEvent.update(newData); syncResult.stats.numUpdates++; } else { App.log.info("Adding " + fileName + " to local calendar"); localEvent = new LocalEvent(localCalendar(), newData, fileName, eTag); localEvent.add(); syncResult.stats.numInserts++; } } else App.log.severe( "Received VCALENDAR with not exactly one VEVENT with UID, but without RECURRENCE-ID; ignoring " + fileName); } }