Caldavsync Sources: src/net/fortuna/ical4j/data/HCalendarParser.java@45d57ecba757 (annotated)

src/net/fortuna/ical4j/data/HCalendarParser.java@45d57ecba757 (annotated)

src/net/fortuna/ical4j/data/HCalendarParser.java

Tue, 10 Feb 2015 19:58:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 10 Feb 2015 19:58:00 +0100
changeset 4: 45d57ecba757
parent 0: fb9019fb1bf7
permissions: -rwxr-xr-x

Upgrade the upgraded ical4j component to use org.apache.commons.lang3.

 /**
  * Copyright (c) 2012, Ben Fortuna
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  *  o Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *
  *  o Redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution.
  *
  *  o Neither the name of Ben Fortuna nor the names of any other contributors
  * may be used to endorse or promote products derived from this software
  * without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 package net.fortuna.ical4j.data;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Reader;
 import java.net.URISyntaxException;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
 import javax.xml.XMLConstants;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.xpath.XPath;
 import javax.xml.xpath.XPathConstants;
 import javax.xml.xpath.XPathException;
 import javax.xml.xpath.XPathExpression;
 import javax.xml.xpath.XPathFactory;
 import net.fortuna.ical4j.model.CalendarException;
 import net.fortuna.ical4j.model.Component;
 import net.fortuna.ical4j.model.Date;
 import net.fortuna.ical4j.model.DateTime;
 import net.fortuna.ical4j.model.Parameter;
 import net.fortuna.ical4j.model.Property;
 import net.fortuna.ical4j.model.parameter.Value;
 import net.fortuna.ical4j.model.property.Version;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.w3c.dom.DOMException;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.xml.sax.InputSource;
 import org.xml.sax.SAXException;
 import org.xml.sax.SAXParseException;
 /**
  * A {@link CalendarParser} that parses XHTML documents that include calendar data marked up with the hCalendar
  * microformat.
  * <p>
  * The parser treats the entire document as a single "vcalendar" context, ignoring any <code>vcalendar</code> elements
  * and adding all components in the document to a single generated calendar.
  * </p>
  * <p>
  * Since hCalendar does not include product information, the <code>PRODID</code> property is omitted from the generated
  * calendar. The hCalendar profile is supposed to define the iCalendar version that it represents, but it does not, so
  * version 2.0 is assumed.
  * </p>
  * <h3>Supported Components</h3>
  * <p>
  * This parser recognizes only "vevent" components.
  * </p>
  * <h3>Supported Properties</h3>
  * <p>
  * This parser recognizes the following properties:
  * </p>
  * <ul>
  * <li>"dtstart"</li>
  * <li>"dtend"</li>
  * <li>"duration"</li>
  * <li>"summary"</li>
  * <li>"uid"</li>
  * <li>"dtstamp"</li>
  * <li>"category"</li>
  * <li>"location"</li>
  * <li>"url"</li>
  * <li>"description"</li>
  * <li>"last-modified"</li>
  * <li>"status"</li>
  * <li>"class"</li>
  * <li>"attendee"</li>
  * <li>"contact"</li>
  * <li>"organizer"</li>
  * </ul>
  * <p>
  * hCalendar allows for some properties to be represented by nested microformat records, including hCard, adr and geo.
  * This parser does not recognize these records. It simply accumulates the text content of any child elements of the
  * property element and uses the resulting string as the property value.
  * </p>
  * <h4>Date and Date-Time Properties</h4>
  * <p>
  * hCalendar date-time values are formatted according to RFC 3339. There is no representation in this specification for
  * time zone ids. All date-times are specified either in UTC or with an offset that can be used to convert the local
  * time into UTC. Neither does hCal provide a reprsentation for floating date-times. Therefore, all date-time values
  * produced by this parser are in UTC.
  * </p>
  * <p>
  * Some examples in the wild provide date and date-time values in iCalendar format rather than RFC 3339 format. Although
  * not technically legal according to spec, these values are accepted. In this case, floating date-times are produced by
  * the parser.
  * </p>
  * <h3>Supported Parameters</h3>
  * <p>
  * hCalendar does not define attributes, nested elements or other information elements representing parameter data.
  * Therefore, this parser does not set any property parameters except as implied by property value data (e.g.
  * VALUE=DATE-TIME or VALUE=DATE for date-time properties).
  * </p>
  */
 public class HCalendarParser implements CalendarParser {
     private static final Log LOG = LogFactory.getLog(HCalendarParser.class);
     private static final DocumentBuilderFactory BUILDER_FACTORY = DocumentBuilderFactory.newInstance();
     private static final XPath XPATH = XPathFactory.newInstance().newXPath();
     private static final XPathExpression XPATH_METHOD;
     private static final XPathExpression XPATH_VEVENTS;
     private static final XPathExpression XPATH_DTSTART;
     private static final XPathExpression XPATH_DTEND;
     private static final XPathExpression XPATH_DURATION;
     private static final XPathExpression XPATH_SUMMARY;
     private static final XPathExpression XPATH_UID;
     private static final XPathExpression XPATH_DTSTAMP;
     private static final XPathExpression XPATH_CATEGORY;
     private static final XPathExpression XPATH_LOCATION;
     private static final XPathExpression XPATH_URL;
     private static final XPathExpression XPATH_DESCRIPTION;
     private static final XPathExpression XPATH_LAST_MODIFIED;
     private static final XPathExpression XPATH_STATUS;
     private static final XPathExpression XPATH_CLASS;
     private static final XPathExpression XPATH_ATTENDEE;
     private static final XPathExpression XPATH_CONTACT;
     private static final XPathExpression XPATH_ORGANIZER;
     private static final XPathExpression XPATH_SEQUENCE;
     private static final XPathExpression XPATH_ATTACH;
     private static final String HCAL_DATE_PATTERN = "yyyy-MM-dd";
     private static final SimpleDateFormat HCAL_DATE_FORMAT = new SimpleDateFormat(HCAL_DATE_PATTERN);
     private static final String HCAL_DATE_TIME_PATTERN = "yyyy-MM-dd'T'HH:mm:ssz";
     private static final SimpleDateFormat HCAL_DATE_TIME_FORMAT = new SimpleDateFormat(HCAL_DATE_TIME_PATTERN);
     static {
         BUILDER_FACTORY.setNamespaceAware(true);
         BUILDER_FACTORY.setIgnoringComments(true);
         XPATH_METHOD = compileExpression("//*[contains(@class, 'method')]");
         XPATH_VEVENTS = compileExpression("//*[contains(@class, 'vevent')]");
         XPATH_DTSTART = compileExpression(".//*[contains(@class, 'dtstart')]");
         XPATH_DTEND = compileExpression(".//*[contains(@class, 'dtend')]");
         XPATH_DURATION = compileExpression(".//*[contains(@class, 'duration')]");
         XPATH_SUMMARY = compileExpression(".//*[contains(@class, 'summary')]");
         XPATH_UID = compileExpression(".//*[contains(@class, 'uid')]");
         XPATH_DTSTAMP = compileExpression(".//*[contains(@class, 'dtstamp')]");
         XPATH_CATEGORY = compileExpression(".//*[contains(@class, 'category')]");
         XPATH_LOCATION = compileExpression(".//*[contains(@class, 'location')]");
         XPATH_URL = compileExpression(".//*[contains(@class, 'url')]");
         XPATH_DESCRIPTION = compileExpression(".//*[contains(@class, 'description')]");
         XPATH_LAST_MODIFIED = compileExpression(".//*[contains(@class, 'last-modified')]");
         XPATH_STATUS = compileExpression(".//*[contains(@class, 'status')]");
         XPATH_CLASS = compileExpression(".//*[contains(@class, 'class')]");
         XPATH_ATTENDEE = compileExpression(".//*[contains(@class, 'attendee')]");
         XPATH_CONTACT = compileExpression(".//*[contains(@class, 'contact')]");
         XPATH_ORGANIZER = compileExpression(".//*[contains(@class, 'organizer')]");
         XPATH_SEQUENCE = compileExpression(".//*[contains(@class, 'sequence')]");
         XPATH_ATTACH = compileExpression(".//*[contains(@class, 'attach')]");
     }
     private static XPathExpression compileExpression(String expr) {
         try {
             return XPATH.compile(expr);
         } catch (XPathException e) {
             throw new CalendarException(e);
         }
     }
     /**
      * {@inheritDoc}
      */
     public void parse(InputStream in, ContentHandler handler) throws IOException, ParserException {
         parse(new InputSource(in), handler);
     }
     /**
      * {@inheritDoc}
      */
     public void parse(Reader in, ContentHandler handler) throws IOException, ParserException {
         parse(new InputSource(in), handler);
     }
     private void parse(InputSource in, ContentHandler handler) throws IOException, ParserException {
         try {
             Document d = BUILDER_FACTORY.newDocumentBuilder().parse(in);
             buildCalendar(d, handler);
         } catch (ParserConfigurationException e) {
             throw new CalendarException(e);
         } catch (SAXException e) {
             if (e instanceof SAXParseException) {
                 SAXParseException pe = (SAXParseException) e;
                 throw new ParserException("Could not parse XML", pe.getLineNumber(), e);
             }
             throw new ParserException(e.getMessage(), -1, e);
         }
     }
     private static NodeList findNodes(XPathExpression expr, Object context) throws ParserException {
         try {
             return (NodeList) expr.evaluate(context, XPathConstants.NODESET);
         } catch (XPathException e) {
             throw new ParserException("Unable to find nodes", -1, e);
         }
     }
     private static Node findNode(XPathExpression expr, Object context) throws ParserException {
         try {
             return (Node) expr.evaluate(context, XPathConstants.NODE);
         } catch (XPathException e) {
             throw new ParserException("Unable to find node", -1, e);
         }
     }
     private static List findElements(XPathExpression expr, Object context) throws ParserException {
         NodeList nodes = findNodes(expr, context);
         ArrayList elements = new ArrayList();
         for (int i = 0; i < nodes.getLength(); i++) {
             Node n = nodes.item(i);
             if (n instanceof Element)
                 elements.add((Element) n);
         }
         return elements;
     }
     private static Element findElement(XPathExpression expr, Object context) throws ParserException {
         Node n = findNode(expr, context);
         if (n == null || (!(n instanceof Element)))
             return null;
         return (Element) n;
     }
     private static String getTextContent(Element element) throws ParserException {
         try {
             String content = element.getFirstChild().getNodeValue();
             if (content != null) {
                 return content.trim().replaceAll("\\s+", " ");
             }
             return content;
         } catch (DOMException e) {
             throw new ParserException("Unable to get text content for element " + element.getNodeName(), -1, e);
         }
     }
     private void buildCalendar(Document d, ContentHandler handler) throws ParserException {
         // "The root class name for hCalendar is "vcalendar". An element with a
         // class name of "vcalendar" is itself called an hCalendar.
         //
         // The root class name for events is "vevent". An element with a class
         // name of "vevent" is itself called an hCalender event.
         //
         // For authoring convenience, both "vevent" and "vcalendar" are
         // treated as root class names for parsing purposes. If a document
         // contains elements with class name "vevent" but not "vcalendar", the
         // entire document has an implied "vcalendar" context."
         // XXX: We assume that the entire document has a single vcalendar
         // context. It is possible that the document contains more than one
         // vcalendar element. In this case, we should probably only process
         // that element and log a warning about skipping the others.
         if (LOG.isDebugEnabled())
             LOG.debug("Building calendar");
         handler.startCalendar();
         // no PRODID, as the using application should set that itself
         handler.startProperty(Property.VERSION);
         try {
             handler.propertyValue(Version.VERSION_2_0.getValue());
         } catch (Exception e) {
         }
         ;
         handler.endProperty(Property.VERSION);
         Element method = findElement(XPATH_METHOD, d);
         if (method != null) {
             buildProperty(method, Property.METHOD, handler);
         }
         List vevents = findElements(XPATH_VEVENTS, d);
         for (Iterator i = vevents.iterator(); i.hasNext();) {
             Element vevent = (Element) i.next();
             buildEvent(vevent, handler);
         }
         // XXX: support other "first class components": vjournal, vtodo,
         // vfreebusy, vavailability, vvenue
         handler.endCalendar();
     }
     private void buildEvent(Element element, ContentHandler handler) throws ParserException {
         if (LOG.isDebugEnabled())
             LOG.debug("Building event");
         handler.startComponent(Component.VEVENT);
         buildProperty(findElement(XPATH_DTSTART, element), Property.DTSTART, handler);
         buildProperty(findElement(XPATH_DTEND, element), Property.DTEND, handler);
         buildProperty(findElement(XPATH_DURATION, element), Property.DURATION, handler);
         buildProperty(findElement(XPATH_SUMMARY, element), Property.SUMMARY, handler);
         buildProperty(findElement(XPATH_UID, element), Property.UID, handler);
         buildProperty(findElement(XPATH_DTSTAMP, element), Property.DTSTAMP, handler);
         List categories = findElements(XPATH_CATEGORY, element);
         for (Iterator i = categories.iterator(); i.hasNext();) {
             Element category = (Element) i.next();
             buildProperty(category, Property.CATEGORIES, handler);
         }
         buildProperty(findElement(XPATH_LOCATION, element), Property.LOCATION, handler);
         buildProperty(findElement(XPATH_URL, element), Property.URL, handler);
         buildProperty(findElement(XPATH_DESCRIPTION, element), Property.DESCRIPTION, handler);
         buildProperty(findElement(XPATH_LAST_MODIFIED, element), Property.LAST_MODIFIED, handler);
         buildProperty(findElement(XPATH_STATUS, element), Property.STATUS, handler);
         buildProperty(findElement(XPATH_CLASS, element), Property.CLASS, handler);
         List attendees = findElements(XPATH_ATTENDEE, element);
         for (Iterator i = attendees.iterator(); i.hasNext();) {
             Element attendee = (Element) i.next();
             buildProperty(attendee, Property.ATTENDEE, handler);
         }
         buildProperty(findElement(XPATH_CONTACT, element), Property.CONTACT, handler);
         buildProperty(findElement(XPATH_ORGANIZER, element), Property.ORGANIZER, handler);
         buildProperty(findElement(XPATH_SEQUENCE, element), Property.SEQUENCE, handler);
         buildProperty(findElement(XPATH_ATTACH, element), Property.ATTACH, handler);
         handler.endComponent(Component.VEVENT);
     }
     private void buildProperty(Element element, String propName, ContentHandler handler) throws ParserException {
         if (element == null)
             return;
         if (LOG.isDebugEnabled())
             LOG.debug("Building property " + propName);
         String className = className(propName);
         String elementName = element.getLocalName().toLowerCase();
         String value = null;
         if (elementName.equals("abbr")) {
             // "If an <abbr> element is used for a property, then the 'title'
             // attribute of the <abbr> element is the value of the property,
             // instead of the contents of the element, which instead provide a
             // human presentable version of the value."
             value = element.getAttribute("title");
             if (StringUtils.isBlank(value))
                 throw new ParserException("Abbr element '" + className + "' requires a non-empty title", -1);
             if (LOG.isDebugEnabled())
                 LOG.debug("Setting value '" + value + "' from title attribute");
         } else if (isHeaderElement(elementName)) {
             // try title first. if that's not set, fall back to text content.
             value = element.getAttribute("title");
             if (!StringUtils.isBlank(value)) {
                 if (LOG.isDebugEnabled())
                     LOG.debug("Setting value '" + value + "' from title attribute");
             } else {
                 value = getTextContent(element);
                 if (LOG.isDebugEnabled())
                     LOG.debug("Setting value '" + value + "' from text content");
             }
         } else if (elementName.equals("a") && isUrlProperty(propName)) {
             value = element.getAttribute("href");
             if (StringUtils.isBlank(value))
                 throw new ParserException("A element '" + className + "' requires a non-empty href", -1);
             if (LOG.isDebugEnabled())
                 LOG.debug("Setting value '" + value + "' from href attribute");
         } else if (elementName.equals("img")) {
             if (isUrlProperty(propName)) {
                 value = element.getAttribute("src");
                 if (StringUtils.isBlank(value))
                     throw new ParserException("Img element '" + className + "' requires a non-empty src", -1);
                 if (LOG.isDebugEnabled())
                     LOG.debug("Setting value '" + value + "' from src attribute");
             } else {
                 value = element.getAttribute("alt");
                 if (StringUtils.isBlank(value))
                     throw new ParserException("Img element '" + className + "' requires a non-empty alt", -1);
                 if (LOG.isDebugEnabled())
                     LOG.debug("Setting value '" + value + "' from alt attribute");
             }
         } else {
             value = getTextContent(element);
             if (!StringUtils.isBlank(value)) {
                 if (LOG.isDebugEnabled())
                     LOG.debug("Setting value '" + value + "' from text content");
             }
         }
         if (StringUtils.isBlank(value)) {
             if (LOG.isDebugEnabled())
                 LOG.debug("Skipping property with empty value");
             return;
         }
         handler.startProperty(propName);
         // if it's a date property, we have to convert from the
         // hCalendar-formatted date (RFC 3339) to an iCalendar-formatted date
         if (isDateProperty(propName)) {
             try {
                 Date date = icalDate(value);
                 value = date.toString();
                 if (!(date instanceof DateTime))
                     try {
                         handler.parameter(Parameter.VALUE, Value.DATE.getValue());
                     } catch (Exception e) {
                     }
             } catch (ParseException e) {
                 throw new ParserException("Malformed date value for element '" + className + "'", -1, e);
             }
         }
         if (isTextProperty(propName)) {
             String lang = element.getAttributeNS(XMLConstants.XML_NS_URI, "lang");
             if (!StringUtils.isBlank(lang))
                 try {
                     handler.parameter(Parameter.LANGUAGE, lang);
                 } catch (Exception e) {
                 }
         }
         // XXX: other parameters?
         try {
             handler.propertyValue(value);
         } catch (URISyntaxException e) {
             throw new ParserException("Malformed URI value for element '" + className + "'", -1, e);
         } catch (ParseException e) {
             throw new ParserException("Malformed value for element '" + className + "'", -1, e);
         } catch (IOException e) {
             throw new CalendarException(e);
         }
         handler.endProperty(propName);
     }
     // "The basic format of hCalendar is to use iCalendar object/property
     // names in lower-case for class names ..."
     /*
      * private static String _icalName(Element element) { return element.getAttribute("class").toUpperCase(); }
      */
     private static String className(String propName) {
         return propName.toLowerCase();
     }
     private static boolean isHeaderElement(String name) {
         return (name.equals("h1") || name.equals("h2") || name.equals("h3")
                 || name.equals("h4") || name.equals("h5") || name
                 .equals("h6"));
     }
     private static boolean isDateProperty(String name) {
         return (name.equals(Property.DTSTART) || name.equals(Property.DTEND) || name.equals(Property.DTSTAMP) || name
                 .equals(Property.LAST_MODIFIED));
     }
     private static boolean isUrlProperty(String name) {
         return (name.equals(Property.URL));
     }
     private static boolean isTextProperty(String name) {
         return (name.equals(Property.SUMMARY) || name.equals(Property.LOCATION) || name.equals(Property.CATEGORIES)
                 || name.equals(Property.DESCRIPTION) || name.equals(Property.ATTENDEE)
                 || name.equals(Property.CONTACT) || name
                 .equals(Property.ORGANIZER));
     }
     private static Date icalDate(String original) throws ParseException {
         // in the real world, some generators use iCalendar formatted
         // dates and date-times, so try parsing those formats first before
         // going to RFC 3339 formats
         if (original.indexOf('T') == -1) {
             // date-only
             try {
                 // for some reason Date's pattern matches yyyy-MM-dd, so
                 // don't check it if we find -
                 if (original.indexOf('-') == -1)
                     return new Date(original);
             } catch (Exception e) {
             }
             return new Date(HCAL_DATE_FORMAT.parse(original));
         }
         try {
             return new DateTime(original);
         } catch (Exception e) {
         }
         // the date-time value can represent its time zone in a few different
         // ways. we have to normalize those to match our pattern.
         String normalized = null;
         if (LOG.isDebugEnabled())
             LOG.debug("normalizing date-time " + original);
         // 2002-10-09T19:00:00Z
         if (original.charAt(original.length() - 1) == 'Z') {
             normalized = original.replaceAll("Z", "GMT-00:00");
         }
         // 2002-10-10T00:00:00+05:00
         else if (original.indexOf("GMT") == -1
                 && (original.charAt(original.length() - 6) == '+' || original.charAt(original.length() - 6) == '-')) {
             String tzId = "GMT" + original.substring(original.length() - 6);
             normalized = original.substring(0, original.length() - 6) + tzId;
         } else {
             // 2002-10-10T00:00:00GMT+05:00
             normalized = original;
         }
         DateTime dt = new DateTime(HCAL_DATE_TIME_FORMAT.parse(normalized));
         // hCalendar does not specify a representation for timezone ids
         // or any other sort of timezone information. the best it does is
         // give us a timezone offset that we can use to convert the local
         // time to UTC. furthermore, it has no representation for floating
         // date-times. therefore, all dates are converted to UTC.
         dt.setUtc(true);
         return dt;
     }
 }

Caldavsync Sources / annotate

src/net/fortuna/ical4j/data/HCalendarParser.java@45d57ecba757 (annotated)

src/net/fortuna/ical4j/data/HCalendarParser.java