Java tutorial
/* * Copyright 2004 Sun Microsystems, Inc. * * 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.sun.syndication.io.impl; import com.sun.syndication.feed.WireFeed; import com.sun.syndication.feed.atom.*; import com.sun.syndication.io.FeedException; import org.jdom2.Document; import org.jdom2.Element; import org.jdom2.Namespace; import org.jdom2.output.XMLOutputter; import java.util.*; /** */ public class Atom03Parser extends BaseWireFeedParser { private static final String ATOM_03_URI = "http://purl.org/atom/ns#"; private static final Namespace ATOM_03_NS = Namespace.getNamespace(ATOM_03_URI); public Atom03Parser() { this("atom_0.3", ATOM_03_NS); } protected Atom03Parser(String type, Namespace ns) { super(type, ns); } protected Namespace getAtomNamespace() { return ATOM_03_NS; } public boolean isMyType(Document document) { Element rssRoot = document.getRootElement(); Namespace defaultNS = rssRoot.getNamespace(); return (defaultNS != null) && defaultNS.equals(getAtomNamespace()); } public WireFeed parse(Document document, boolean validate) throws IllegalArgumentException, FeedException { if (validate) { validateFeed(document); } Element rssRoot = document.getRootElement(); return parseFeed(rssRoot); } protected void validateFeed(Document document) throws FeedException { // TBD // here we have to validate the Feed against a schema or whatever // not sure how to do it // one posibility would be to produce an ouput and attempt to parse it again // with validation turned on. // otherwise will have to check the document elements by hand. } protected WireFeed parseFeed(Element eFeed) { com.sun.syndication.feed.atom.Feed feed = new com.sun.syndication.feed.atom.Feed(getType()); Element e = eFeed.getChild("title", getAtomNamespace()); if (e != null) { feed.setTitleEx(parseContent(e)); } List eList = eFeed.getChildren("link", getAtomNamespace()); feed.setAlternateLinks(parseAlternateLinks(eList)); feed.setOtherLinks(parseOtherLinks(eList)); e = eFeed.getChild("author", getAtomNamespace()); if (e != null) { List authors = new ArrayList(); authors.add(parsePerson(e)); feed.setAuthors(authors); } eList = eFeed.getChildren("contributor", getAtomNamespace()); if (eList.size() > 0) { feed.setContributors(parsePersons(eList)); } e = eFeed.getChild("tagline", getAtomNamespace()); if (e != null) { feed.setTagline(parseContent(e)); } e = eFeed.getChild("id", getAtomNamespace()); if (e != null) { feed.setId(e.getText()); } e = eFeed.getChild("generator", getAtomNamespace()); if (e != null) { Generator gen = new Generator(); gen.setValue(e.getText()); String att = getAttributeValue(e, "url"); if (att != null) { gen.setUrl(att); } att = getAttributeValue(e, "version"); if (att != null) { gen.setVersion(att); } feed.setGenerator(gen); } e = eFeed.getChild("copyright", getAtomNamespace()); if (e != null) { feed.setCopyright(e.getText()); } e = eFeed.getChild("info", getAtomNamespace()); if (e != null) { feed.setInfo(parseContent(e)); } e = eFeed.getChild("modified", getAtomNamespace()); if (e != null) { feed.setModified(DateParser.parseDate(e.getText())); } feed.setModules(parseFeedModules(eFeed)); eList = eFeed.getChildren("entry", getAtomNamespace()); if (eList.size() > 0) { feed.setEntries(parseEntries(eList)); } List foreignMarkup = extractForeignMarkup(eFeed, feed, getAtomNamespace()); if (foreignMarkup.size() > 0) { feed.setForeignMarkup(foreignMarkup); } return feed; } private Link parseLink(Element eLink) { Link link = new Link(); String att = getAttributeValue(eLink, "rel"); if (att != null) { link.setRel(att); } att = getAttributeValue(eLink, "type"); if (att != null) { link.setType(att); } att = getAttributeValue(eLink, "href"); if (att != null) { link.setHref(att); } return link; } // List(Elements) -> List(Link) private List parseLinks(List eLinks, boolean alternate) { List links = new ArrayList(); for (int i = 0; i < eLinks.size(); i++) { Element eLink = (Element) eLinks.get(i); String rel = getAttributeValue(eLink, "rel"); if (alternate) { if ("alternate".equals(rel)) { links.add(parseLink(eLink)); } } else { if (!("alternate".equals(rel))) { links.add(parseLink(eLink)); } } } return (links.size() > 0) ? links : null; } // List(Elements) -> List(Link) private List parseAlternateLinks(List eLinks) { return parseLinks(eLinks, true); } // List(Elements) -> List(Link) private List parseOtherLinks(List eLinks) { return parseLinks(eLinks, false); } private Person parsePerson(Element ePerson) { Person person = new Person(); Element e = ePerson.getChild("name", getAtomNamespace()); if (e != null) { person.setName(e.getText()); } e = ePerson.getChild("url", getAtomNamespace()); if (e != null) { person.setUrl(e.getText()); } e = ePerson.getChild("email", getAtomNamespace()); if (e != null) { person.setEmail(e.getText()); } return person; } // List(Elements) -> List(Persons) private List parsePersons(List ePersons) { List persons = new ArrayList(); for (int i = 0; i < ePersons.size(); i++) { persons.add(parsePerson((Element) ePersons.get(i))); } return (persons.size() > 0) ? persons : null; } private Content parseContent(Element e) { String value = null; String type = getAttributeValue(e, "type"); type = (type != null) ? type : "text/plain"; String mode = getAttributeValue(e, "mode"); if (mode == null) { mode = Content.XML; // default to xml content } if (mode.equals(Content.ESCAPED)) { // do nothing XML Parser took care of this value = e.getText(); } else if (mode.equals(Content.BASE64)) { value = Base64.decode(e.getText()); } else if (mode.equals(Content.XML)) { XMLOutputter outputter = new XMLOutputter(); List eContent = e.getContent(); Iterator i = eContent.iterator(); while (i.hasNext()) { org.jdom2.Content c = (org.jdom2.Content) i.next(); if (c instanceof Element) { Element eC = (Element) c; if (eC.getNamespace().equals(getAtomNamespace())) { ((Element) c).setNamespace(Namespace.NO_NAMESPACE); } } } value = outputter.outputString(eContent); } Content content = new Content(); content.setType(type); content.setMode(mode); content.setValue(value); return content; } // List(Elements) -> List(Entries) private List parseEntries(List eEntries) { List entries = new ArrayList(); for (int i = 0; i < eEntries.size(); i++) { entries.add(parseEntry((Element) eEntries.get(i))); } return (entries.size() > 0) ? entries : null; } private Entry parseEntry(Element eEntry) { Entry entry = new Entry(); Element e = eEntry.getChild("title", getAtomNamespace()); if (e != null) { entry.setTitleEx(parseContent(e)); } List eList = eEntry.getChildren("link", getAtomNamespace()); entry.setAlternateLinks(parseAlternateLinks(eList)); entry.setOtherLinks(parseOtherLinks(eList)); e = eEntry.getChild("author", getAtomNamespace()); if (e != null) { List authors = new ArrayList(); authors.add(parsePerson(e)); entry.setAuthors(authors); } eList = eEntry.getChildren("contributor", getAtomNamespace()); if (eList.size() > 0) { entry.setContributors(parsePersons(eList)); } e = eEntry.getChild("id", getAtomNamespace()); if (e != null) { entry.setId(e.getText()); } e = eEntry.getChild("modified", getAtomNamespace()); if (e != null) { entry.setModified(DateParser.parseDate(e.getText())); } e = eEntry.getChild("issued", getAtomNamespace()); if (e != null) { entry.setIssued(DateParser.parseDate(e.getText())); } e = eEntry.getChild("created", getAtomNamespace()); if (e != null) { entry.setCreated(DateParser.parseDate(e.getText())); } e = eEntry.getChild("summary", getAtomNamespace()); if (e != null) { entry.setSummary(parseContent(e)); } eList = eEntry.getChildren("content", getAtomNamespace()); if (eList.size() > 0) { List content = new ArrayList(); for (int i = 0; i < eList.size(); i++) { content.add(parseContent((Element) eList.get(i))); } entry.setContents(content); } entry.setModules(parseItemModules(eEntry)); List foreignMarkup = extractForeignMarkup(eEntry, entry, getAtomNamespace()); if (foreignMarkup.size() > 0) { entry.setForeignMarkup(foreignMarkup); } return entry; } }