Java tutorial
/* * Copyright (c) 2004-2006 Marco Maccaferri and others. * 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: * Marco Maccaferri - initial API and implementation */ package org.eclipsetrader.news.internal.connectors; import java.io.File; import java.net.URL; import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Set; import javax.xml.bind.JAXBContext; import javax.xml.bind.JAXBElement; import javax.xml.bind.Unmarshaller; import javax.xml.bind.ValidationEvent; import javax.xml.bind.ValidationEventHandler; import javax.xml.transform.stream.StreamSource; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.UsernamePasswordCredentials; import org.apache.commons.httpclient.auth.AuthScope; import org.eclipse.core.net.proxy.IProxyData; import org.eclipse.core.net.proxy.IProxyService; import org.eclipse.core.runtime.CoreException; import org.eclipse.core.runtime.IConfigurationElement; import org.eclipse.core.runtime.IExecutableExtension; import org.eclipse.core.runtime.IProgressMonitor; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.Status; import org.eclipse.core.runtime.jobs.IJobChangeEvent; import org.eclipse.core.runtime.jobs.Job; import org.eclipse.core.runtime.jobs.JobChangeAdapter; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipsetrader.core.instruments.ISecurity; import org.eclipsetrader.news.core.IHeadLine; import org.eclipsetrader.news.core.INewsProvider; import org.eclipsetrader.news.core.INewsService; import org.eclipsetrader.news.core.INewsServiceRunnable; import org.eclipsetrader.news.internal.Activator; import org.eclipsetrader.news.internal.repository.HeadLine; import org.osgi.framework.BundleContext; import org.osgi.framework.ServiceReference; import com.sun.syndication.feed.synd.SyndEntry; import com.sun.syndication.feed.synd.SyndFeed; import com.sun.syndication.fetcher.impl.FeedFetcherCache; import com.sun.syndication.fetcher.impl.HashMapFeedInfoCache; import com.sun.syndication.fetcher.impl.HttpClientFeedFetcher; public class RSSNewsProvider implements INewsProvider, IExecutableExtension { public static final String HEADLINES_FILE = "rss.xml"; //$NON-NLS-1$ private String id; private String name; private FeedFetcherCache feedInfoCache = HashMapFeedInfoCache.getInstance(); private HttpClientFeedFetcher fetcher = new HttpClientFeedFetcher(feedInfoCache); private INewsService newsService; private boolean started; static private List<HeadLine> oldItems = new ArrayList<HeadLine>(); private JobChangeAdapter jobChangeListener = new JobChangeAdapter() { @Override public void done(IJobChangeEvent event) { IPreferenceStore store = Activator.getDefault().getPreferenceStore(); int interval = store.getInt(Activator.PREFS_UPDATE_INTERVAL); job.schedule(interval * 60 * 1000); } }; private Job job = new Job("RSS Subscriptions") { @Override protected IStatus run(IProgressMonitor monitor) { return jobRunner(monitor); } }; public RSSNewsProvider() { } /* (non-Javadoc) * @see org.eclipse.core.runtime.IExecutableExtension#setInitializationData(org.eclipse.core.runtime.IConfigurationElement, java.lang.String, java.lang.Object) */ @Override public void setInitializationData(IConfigurationElement config, String propertyName, Object data) throws CoreException { id = config.getAttribute("id"); name = config.getAttribute("name"); } /* (non-Javadoc) * @see org.eclipsetrader.news.core.INewsProvider#getId() */ @Override public String getId() { return id; } /* (non-Javadoc) * @see org.eclipsetrader.news.core.INewsProvider#getName() */ @Override public String getName() { return name; } /* (non-Javadoc) * @see org.eclipsetrader.news.core.INewsProvider#getHeadLines() */ @Override public IHeadLine[] getHeadLines() { return new IHeadLine[0]; } /* (non-Javadoc) * @see org.eclipsetrader.news.core.INewsProvider#start() */ @Override public void start() { if (!started) { job.schedule(5 * 1000); job.addJobChangeListener(jobChangeListener); started = true; } } /* (non-Javadoc) * @see org.eclipsetrader.news.core.INewsProvider#stop() */ @Override public void stop() { if (started) { job.removeJobChangeListener(jobChangeListener); job.cancel(); started = false; } } /* (non-Javadoc) * @see org.eclipsetrader.news.core.INewsProvider#refresh() */ @Override public void refresh() { job.removeJobChangeListener(jobChangeListener); job.cancel(); if (started) { job.addJobChangeListener(jobChangeListener); } job.schedule(0); } protected IStatus jobRunner(IProgressMonitor monitor) { final List<IHeadLine> list = new ArrayList<IHeadLine>(); FeedSource[] sources = getActiveSubscriptions(); monitor.beginTask("Updating RSS Subscriptions", sources.length); try { for (int i = 0; i < sources.length; i++) { try { HeadLine[] headLines = update(new URL(sources[i].getUrl()), sources[i].getName()); for (HeadLine headLine : headLines) { if (!oldItems.contains(headLine)) { headLine.setRecent(true); oldItems.add(headLine); list.add(headLine); } } } catch (Exception e) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error updating headlines from " + sources[i].getUrl(), null); //$NON-NLS-1$ Activator.getDefault().getLog().log(status); } finally { monitor.worked(1); } } final INewsService service = getNewsService(); service.runInService(new INewsServiceRunnable() { @Override public IStatus run(IProgressMonitor monitor) throws Exception { service.addHeadLines(list.toArray(new IHeadLine[list.size()])); return Status.OK_STATUS; } }, null); } finally { monitor.done(); } return Status.OK_STATUS; } protected void resetRecentFlag() { final List<HeadLine> updated = new ArrayList<HeadLine>(); for (HeadLine headLine : oldItems) { if (headLine.isRecent()) { headLine.setRecent(false); updated.add(headLine); } } final INewsService service = getNewsService(); service.runInService(new INewsServiceRunnable() { @Override public IStatus run(IProgressMonitor monitor) throws Exception { service.updateHeadLines(updated.toArray(new IHeadLine[updated.size()])); return Status.OK_STATUS; } }, null); } protected FeedSource[] getActiveSubscriptions() { List<FeedSource> list = new ArrayList<FeedSource>(); try { File file = Activator.getDefault().getStateLocation().append(HEADLINES_FILE).toFile(); if (file.exists()) { JAXBContext jaxbContext = JAXBContext.newInstance(FeedSource[].class); Unmarshaller unmarshaller = jaxbContext.createUnmarshaller(); unmarshaller.setEventHandler(new ValidationEventHandler() { @Override public boolean handleEvent(ValidationEvent event) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error validating XML: " + event.getMessage(), null); //$NON-NLS-1$ Activator.getDefault().getLog().log(status); return true; } }); JAXBElement<FeedSource[]> element = unmarshaller.unmarshal(new StreamSource(file), FeedSource[].class); for (FeedSource source : element.getValue()) { if (source.isEnabled()) { list.add(source); } } } } catch (Exception e) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error reading RSS subscriptions", //$NON-NLS-1$ null); Activator.getDefault().getLog().log(status); } return list.toArray(new FeedSource[list.size()]); } private HeadLine[] update(URL feedUrl, String source) { Map<String, SyndEntry> titles = new HashMap<String, SyndEntry>(); Map<SyndEntry, Set<ISecurity>> entries = new HashMap<SyndEntry, Set<ISecurity>>(); Set<HeadLine> headLines = new HashSet<HeadLine>(); try { HttpClient client = new HttpClient(); client.getHttpConnectionManager().getParams().setConnectionTimeout(5000); if (Activator.getDefault() != null) { BundleContext context = Activator.getDefault().getBundle().getBundleContext(); ServiceReference reference = context.getServiceReference(IProxyService.class.getName()); if (reference != null) { IProxyService proxy = (IProxyService) context.getService(reference); IProxyData data = proxy.getProxyDataForHost(feedUrl.getHost(), IProxyData.HTTP_PROXY_TYPE); if (data != null) { if (data.getHost() != null) { client.getHostConfiguration().setProxy(data.getHost(), data.getPort()); } if (data.isRequiresAuthentication()) { client.getState().setProxyCredentials(AuthScope.ANY, new UsernamePasswordCredentials(data.getUserId(), data.getPassword())); } } context.ungetService(reference); } } SyndFeed feed = fetcher.retrieveFeed(feedUrl, client); for (Iterator<?> iter = feed.getEntries().iterator(); iter.hasNext();) { SyndEntry entry = (SyndEntry) iter.next(); if (titles.containsKey(entry.getTitle())) { entry = titles.get(entry.getTitle()); } else { titles.put(entry.getTitle(), entry); } Set<ISecurity> set = entries.get(entry); if (set == null) { set = new HashSet<ISecurity>(); entries.put(entry, set); } } for (SyndEntry entry : entries.keySet()) { Set<ISecurity> set = entries.get(entry); String url = entry.getLink(); if (url.indexOf('*') != -1) { url = url.substring(url.indexOf('*') + 1); } String title = entry.getTitle(); if (title.endsWith(")")) { int s = title.lastIndexOf('('); if (s != -1) { source = title.substring(s + 1, title.length() - 1); if (source.startsWith("at ")) { source = source.substring(3); } title = title.substring(0, s - 1).trim(); } } HeadLine headLine = new HeadLine(entry.getPublishedDate(), source, title, set.toArray(new ISecurity[set.size()]), url); headLines.add(headLine); } } catch (Exception e) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error reading RSS subscription " + feedUrl.toString(), e); //$NON-NLS-1$ Activator.getDefault().getLog().log(status); } return headLines.toArray(new HeadLine[headLines.size()]); } protected INewsService getNewsService() { if (newsService == null) { BundleContext context = Activator.getDefault().getBundle().getBundleContext(); ServiceReference serviceReference = context.getServiceReference(INewsService.class.getName()); if (serviceReference != null) { newsService = (INewsService) context.getService(serviceReference); context.ungetService(serviceReference); } } return newsService; } }