/*
* Encog(tm) Core v3.0 - Java Version
* http://www.heatonresearch.com/encog/
* http://code.google.com/p/encog-java/
* Copyright 2008-2011 Heaton Research, 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.
*
* For more information on Heaton Research copyrights, licenses
* and trademarks visit:
* http://www.heatonresearch.com/copyright
*/
package org.encog.bot.rss;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.encog.bot.BotError;
import org.encog.util.logging.EncogLogging;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
/**
* This is the class that actually parses the RSS and builds a collection of
* RSSItems. To make use of this class call the load method with a URL that
* points to RSS.
*/
public class RSS {
/**
* Simple utility method that obtains the text of an XML node.
*
* @param n
* The XML node.
* @return The text of the specified XML node.
*/
public static String getXMLText(final Node n) {
final NodeList list = n.getChildNodes();
for (int i = 0; i < list.getLength(); i++) {
final Node n2 = list.item(i);
if (n2.getNodeType() == Node.TEXT_NODE) {
return n2.getNodeValue();
}
}
return null;
}
/**
* Simple utility function that converts a RSS formatted date into a Java
* date.
*
* @param datestr
* The RSS formatted date.
* @return A Java java.util.date
*/
public static Date parseDate(final String datestr) {
try {
final DateFormat formatter = new SimpleDateFormat(
"E, dd MMM yyyy HH:mm:ss Z");
final Date date = formatter.parse(datestr);
return date;
} catch (final Exception e) {
return null;
}
}
/**
* All of the attributes for this RSS document.
*/
private final Map<String, String> attributes
= new HashMap<String, String>();
/**
* All RSS items, or stories, found.
*/
private final List<RSSItem> items = new ArrayList<RSSItem>();
/**
* Get the list of attributes.
*
* @return the attributes
*/
public final Map<String, String> getAttributes() {
return this.attributes;
}
/**
* @return the items
*/
public final List<RSSItem> getItems() {
return this.items;
}
/**
* Load all RSS data from the specified URL.
*
* @param url The URL to load.
*/
public final void load(final URL url) {
load(url, -1);
}
/**
* Load all RSS data from the specified URL.
*
* @param url
* URL that contains XML data.
* @param timeout The timeout value.
*/
public final void load(final URL url, final int timeout) {
try {
EncogLogging.log(EncogLogging.LEVEL_DEBUG, "Loading RSS from:"
+ url);
final URLConnection http = url.openConnection();
if (timeout > 0) {
http.setConnectTimeout(timeout);
}
http.setRequestProperty("User-Agent",
"Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; "
+ "Win64; x64; Trident/4.0)");
final InputStream is = http.getInputStream();
final DocumentBuilderFactory factory = DocumentBuilderFactory
.newInstance();
final Document d = factory.newDocumentBuilder().parse(is);
final Element e = d.getDocumentElement();
final NodeList nl = e.getChildNodes();
for (int i = 0; i < nl.getLength(); i++) {
final Node node = nl.item(i);
final String nodename = node.getNodeName();
// RSS 2.0
if (nodename.equalsIgnoreCase("channel")) {
loadChannel(node);
// RSS 1.0
} else if (nodename.equalsIgnoreCase("item")) {
loadItem(node);
}
}
} catch (final IOException e) {
EncogLogging.log(e);
throw new BotError(e);
} catch (final SAXException e) {
EncogLogging.log(e);
throw new BotError(e);
} catch (final ParserConfigurationException e) {
EncogLogging.log(e);
throw new BotError(e);
}
}
/**
* Load the channle node.
*
* @param channel
* A node that contains a channel.
*/
private void loadChannel(final Node channel) {
final NodeList nl = channel.getChildNodes();
for (int i = 0; i < nl.getLength(); i++) {
final Node node = nl.item(i);
final String nodename = node.getNodeName();
if (nodename.equalsIgnoreCase("item")) {
loadItem(node);
} else {
if (node.getNodeType() != Node.TEXT_NODE) {
this.attributes.put(nodename, RSS.getXMLText(node));
}
}
}
}
/**
* Load the specified RSS item, or story.
*
* @param item
* A XML node that contains a RSS item.
*/
private void loadItem(final Node item) {
final RSSItem rssItem = new RSSItem();
rssItem.load(item);
this.items.add(rssItem);
EncogLogging
.log(EncogLogging.LEVEL_DEBUG, "Loaded RSS item:" + rssItem);
}
/**
* {@inheritDoc}
*/
@Override
public final String toString() {
final StringBuilder str = new StringBuilder();
final Set<String> set = this.attributes.keySet();
for (final String item : set) {
str.append(item);
str.append('=');
str.append(this.attributes.get(item));
str.append('\n');
}
str.append("Items:\n");
for (final RSSItem item : this.items) {
str.append(item.toString());
str.append('\n');
}
return str.toString();
}
}