RssClientSOContainer.java

/**
 * Copyright (c) 2006 Parity Communications, Inc. 
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     Sergey Yakovlev - initial API and implementation
 */
package org.eclipse.ecf.internal.provider.rss.container;

import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.ecf.core.ContainerFactory;
import org.eclipse.ecf.core.ContainerTypeDescription;
import org.eclipse.ecf.core.IContainerListener;
import org.eclipse.ecf.core.events.ContainerConnectedEvent;
import org.eclipse.ecf.core.events.IContainerEvent;
import org.eclipse.ecf.core.identity.ID;
import org.eclipse.ecf.core.identity.IDCreateException;
import org.eclipse.ecf.core.identity.IDFactory;
import org.eclipse.ecf.core.identity.Namespace;
import org.eclipse.ecf.core.identity.StringID;
import org.eclipse.ecf.core.sharedobject.ISharedObject;
import org.eclipse.ecf.core.sharedobject.SharedObjectCreateException;
import org.eclipse.ecf.core.sharedobject.SharedObjectDescription;
import org.eclipse.ecf.core.sharedobject.SharedObjectFactory;
import org.eclipse.ecf.core.sharedobject.SharedObjectTypeDescription;
import org.eclipse.ecf.core.sharedobject.events.ISharedObjectActivatedEvent;
import org.eclipse.ecf.core.sharedobject.events.ISharedObjectDeactivatedEvent;
import org.eclipse.ecf.core.util.ECFException;
import org.eclipse.ecf.core.util.Trace;
import org.eclipse.ecf.datashare.IChannel;
import org.eclipse.ecf.datashare.IChannelConfig;
import org.eclipse.ecf.datashare.IChannelContainerListener;
import org.eclipse.ecf.datashare.IChannelListener;
import org.eclipse.ecf.datashare.events.IChannelContainerChannelActivatedEvent;
import org.eclipse.ecf.datashare.events.IChannelContainerChannelDeactivatedEvent;
import org.eclipse.ecf.datashare.events.IChannelContainerEvent;
import org.eclipse.ecf.datashare.events.IChannelEvent;
import org.eclipse.ecf.datashare.mergeable.IMergeableChannel;
import org.eclipse.ecf.datashare.mergeable.IMergeableChannelContainerAdapter;
import org.eclipse.ecf.internal.provider.rss.RssDebugOptions;
import org.eclipse.ecf.internal.provider.rss.RssPlugin;
import org.eclipse.ecf.internal.provider.rss.http.HttpClient;
import org.eclipse.ecf.provider.comm.ConnectionCreateException;
import org.eclipse.ecf.provider.comm.ISynchAsynchConnection;
import org.eclipse.ecf.provider.generic.ClientSOContainer;
import org.eclipse.ecf.provider.generic.SOContainerConfig;
import org.eclipse.higgins.rsse.RssFeed;
import org.eclipse.higgins.rsse.RssItem;
import org.eclipse.higgins.rsse.parser.FeedParser;
import org.eclipse.higgins.rsse.parser.ParseException;
import org.eclipse.higgins.rsse.util.RssVersion;

/**
 * The RssClientSOContainer implements the basic RSS client functionality.
 * 
 */
public class RssClientSOContainer extends ClientSOContainer implements IMergeableChannelContainerAdapter {

	public static final String DEFAULT_COMM_NAME = org.eclipse.ecf.internal.provider.rss.http.HttpClient.class.getName();
	public static final int DEFAULT_KEEPALIVE = 30000;

	int keepAlive = 0;

	protected List channelContainerListener = Collections.synchronizedList(new ArrayList());

	protected void fireChannelContainerListeners(IChannelContainerEvent event) {
		synchronized (channelContainerListener) {
			for (final Iterator i = channelContainerListener.iterator(); i.hasNext();) {
				final IChannelContainerListener l = (IChannelContainerListener) i.next();
				if (l != null)
					l.handleChannelContainerEvent(event);
			}
		}
	}

	/**
	 * The constructors
	 * 
	 * @throws IDCreateException
	 */
	public RssClientSOContainer() throws IDCreateException {
		this(DEFAULT_KEEPALIVE);
	}

	public RssClientSOContainer(int keepAlive) throws IDCreateException {
		this(IDFactory.getDefault().createGUID(), keepAlive);
	}

	public RssClientSOContainer(String userhost) throws IDCreateException {
		this(userhost, DEFAULT_KEEPALIVE);
	}

	public RssClientSOContainer(String userhost, int keepAlive) throws IDCreateException {
		this(IDFactory.getDefault().createStringID(userhost), keepAlive);
	}

	public RssClientSOContainer(ID containerId, int keepAlive) throws IDCreateException {
		super(new SOContainerConfig(containerId));
		this.keepAlive = keepAlive;
		this.addListener(new ContainerListener());
	}

	protected class ContainerListener implements IContainerListener {
		public void handleEvent(final IContainerEvent evt) {
			if (evt instanceof ISharedObjectActivatedEvent) {
				final ISharedObjectActivatedEvent soae = (ISharedObjectActivatedEvent) evt;
				fireChannelContainerListeners(new IChannelContainerChannelActivatedEvent() {
					public ID getChannelID() {
						return soae.getActivatedID();
					}

					public ID getChannelContainerID() {
						return soae.getLocalContainerID();
					}

					public String toString() {
						final StringBuffer buf = new StringBuffer("ChannelActivatedEvent[");
						buf.append("channelid=").append(soae.getActivatedID()).append(";");
						buf.append("containerid=").append(soae.getLocalContainerID()).append("]");
						return buf.toString();
					}
				});
			} else if (evt instanceof ISharedObjectDeactivatedEvent) {
				final ISharedObjectDeactivatedEvent sode = (ISharedObjectDeactivatedEvent) evt;
				fireChannelContainerListeners(new IChannelContainerChannelDeactivatedEvent() {
					public ID getChannelID() {
						return sode.getDeactivatedID();
					}

					public ID getChannelContainerID() {
						return sode.getLocalContainerID();
					}

					public String toString() {
						final StringBuffer buf = new StringBuffer("ChannelDeactivatedEvent[");
						buf.append("channelid=").append(sode.getDeactivatedID()).append(";");
						buf.append("containerid=").append(sode.getLocalContainerID()).append("]");
						return buf.toString();
					}
				});
			}
		}
	}

	protected void trace(String msg) {
		Trace.trace(RssPlugin.PLUGIN_ID, RssDebugOptions.DEBUG, msg);
	}

	protected void dumpStack(String msg, Throwable e) {
		Trace.catching(RssPlugin.PLUGIN_ID, RssDebugOptions.EXCEPTIONS_CATCHING, this.getClass(), "", e);
	}

	protected ISynchAsynchConnection createConnection(ID remoteSpace, Object data) throws ConnectionCreateException {
		trace("createConnection:" + remoteSpace + ":" + data);
		// Object[] args = { new Integer(keepAlive) };
		final ISynchAsynchConnection conn = new HttpClient(receiver);
		return conn;
	}

	protected ID handleConnectResponse(ID originalTarget, Object serverData) throws Exception {
		trace("handleConnectResponse:" + originalTarget + ":" + serverData);
		if (originalTarget != null && !originalTarget.equals(getID())) {
			addNewRemoteMember(originalTarget, null);
			// notify listeners
			fireContainerEvent(new ContainerConnectedEvent(this.getID(), originalTarget));
		}
		return originalTarget;
	}

	public RssFeed receiveFeed(String feedPath) throws IOException {
		RssFeed feed = null;
		final ISynchAsynchConnection connection = getConnection();
		synchronized (connection) {
			if (connection.isConnected()) {
				try {
					feed = FeedParser.parse((byte[]) connection.sendSynch(null, feedPath.getBytes()));
				} catch (final ParseException e) {
					throw new IOException(e.getMessage());
				}
			}
		}
		return feed;
	}

	public Object getAdapter(Class clazz) {
		if (clazz.equals(IMergeableChannelContainerAdapter.class)) {
			return this;
		} else {
			return super.getAdapter(clazz);
		}
	}

	public Namespace getChannelNamespace() {
		return IDFactory.getDefault().getNamespaceByName(StringID.class.getName());
	}

	public IMergeableChannel createMergeableChannel(ID channelID, IChannelListener listener, Map properties) throws ECFException {
		return createChannel(channelID, listener, properties);
	}

	public IMergeableChannel createChannel(final ID channelID, final IChannelListener listener, final Map properties) throws ECFException {
		return createChannel(new IChannelConfig() {

			public ID getID() {
				return channelID;
			}

			public IChannelListener getListener() {
				return listener;
			}

			public Object getAdapter(Class adapter) {
				return null;
			}

			public Map getProperties() {
				return properties;
			}
		});
	}

	public IMergeableChannel createChannel(IChannelConfig newChannelConfig) throws ECFException {
		final IChannelListener listener = newChannelConfig.getListener();
		final SharedObjectDescription sodesc = new SharedObjectDescription(FeedSharedObject.class, IDFactory.getDefault().createGUID(), new HashMap());
		final SharedObjectTypeDescription sotypedesc = sodesc.getTypeDescription();
		ISharedObject sharedObject = null;
		if (sotypedesc.getName() != null) {
			sharedObject = SharedObjectFactory.getDefault().createSharedObject(sotypedesc, new Object[] {listener});
		} else {
			sharedObject = createSharedObject(sotypedesc, listener);
		}
		final IMergeableChannel channel = (IMergeableChannel) sharedObject.getAdapter(IMergeableChannel.class);
		if (channel == null) {
			throw new SharedObjectCreateException("Cannot coerce object " + channel + " to be of type IChannel");
		}
		ID newID = sodesc.getID();
		if (newID == null) {
			newID = IDFactory.getDefault().createGUID();
		}
		Map properties = sodesc.getProperties();
		if (properties == null) {
			properties = new HashMap();
		}
		// Now add channel to container...this will block
		getSharedObjectManager().addSharedObject(newID, sharedObject, properties);
		return channel;
	}

	private ISharedObject createSharedObject(SharedObjectTypeDescription sotypedesc, IChannelListener listener) throws SharedObjectCreateException {
		Class clazz;
		try {
			clazz = Class.forName(sotypedesc.getClassName());
		} catch (final ClassNotFoundException e) {
			throw new SharedObjectCreateException("No constructor for shared object of class " + sotypedesc.getClassName(), e);
		}
		Constructor cons = null;
		try {
			cons = clazz.getDeclaredConstructor(new Class[] {IChannelListener.class});
		} catch (final NoSuchMethodException e) {
			throw new SharedObjectCreateException("No constructor for shared object of class " + sotypedesc.getClassName(), e);
		}
		ISharedObject so = null;
		try {
			so = (ISharedObject) cons.newInstance(new Object[] {listener});
		} catch (final Exception e) {
			throw new SharedObjectCreateException("Cannot create instance of class " + sotypedesc.getClassName(), e);
		}
		return so;
	}

	public IChannel getChannel(ID channelID) {
		return (IChannel) getSharedObjectManager().getSharedObject(channelID);
	}

	public boolean removeChannel(ID channelID) {
		return (getSharedObjectManager().removeSharedObject(channelID) != null);
	}

	public static final void main(String[] args) throws Exception {
		// Get server identity
		// String targetURL =
		// "http://"+java.net.InetAddress.getLocalHost().getHostName();
		String targetURL = "http://feeds.feedburner.com";
		if (args.length > 0) {
			targetURL = args[0];
		}
		final ContainerTypeDescription contd = new ContainerTypeDescription(RssContainerInstantiator.class.getName(), RssContainerInstantiator.class.getName(), null);
		ContainerFactory.getDefault().addDescription(contd);

		final RssClientSOContainer container = new RssClientSOContainer();
		// now connect to rss service
		final ID serverID = IDFactory.getDefault().createStringID(targetURL);
		container.connect(serverID, null);
		// get IMergeableChannelContainer adapter
		final IMergeableChannelContainerAdapter channelContainer = (IMergeableChannelContainerAdapter) container.getAdapter(IMergeableChannelContainerAdapter.class);
		// create channel listener
		final IChannelListener listener = new IChannelListener() {
			public void handleChannelEvent(IChannelEvent event) {
				System.out.println("listener.handleChannelEvent(" + event + ")");
			}
		};
		// create a new channel
		final ID channelID = IDFactory.getDefault().createStringID("/reuters/worldNews/");
		// ID channelID = IDFactory.getDefault().createStringID("/feed.xml");
		final IMergeableChannel channel = channelContainer.createMergeableChannel(channelID, listener, new HashMap());
		if (channel instanceof FeedSharedObject) {
			// get remote feed (subscribed)
			final RssFeed remoteFeed = ((FeedSharedObject) channel).getFeed();
			// get local feed (published)
			final File feedFile = new File("feed.xml");
			RssFeed localFeed = RssFeed.load(feedFile);
			if (localFeed == null) {
				localFeed = new RssFeed(remoteFeed.getTitle(), remoteFeed.getLink(), remoteFeed.getDescription());
				localFeed.setVersion(RssVersion.RSS_2_0);
			}
			// merge remote feed with local one
			localFeed.merge(remoteFeed);
			// add a new item to feed
			localFeed.addItem(new RssItem("New Google Item", "This is a new item", "http://www.google.com"));
			// publish updated feed
			localFeed.save(feedFile);
			// print item titles
			final java.util.List items = localFeed.getItems();
			for (int i = 0; i < items.size(); i++) {
				System.out.println(" " + i + " " + ((RssItem) items.get(i)).getTitle());
			}
		}
		// remove the channel
		channelContainer.removeChannel(channelID);
		// disconnect the service
		container.disconnect();
		container.dispose();
		System.out.println("Exiting.");
	}

	public void addListener(IChannelContainerListener listener) {
		channelContainerListener.add(listener);
	}

	public void removeListener(IChannelContainerListener listener) {
		channelContainerListener.add(listener);
	}
}