Examples with GateAwareObjectInputStream gate.persist.GateAwareObjectInputStream used on opensource projects

Example 1 with GateAwareObjectInputStream

use of gate.persist.GateAwareObjectInputStream in project gate-core by GateNLP.

the class PersistenceManager method loadObjectFromUrl.

public static Object loadObjectFromUrl(URL url) throws PersistenceException, IOException, ResourceInstantiationException {
    if (!Gate.isInitialised())
        throw new ResourceInstantiationException("You must call Gate.init() before you can restore resources");
    ProgressListener pListener = (ProgressListener) Gate.getListeners().get("gate.event.ProgressListener");
    StatusListener sListener = (gate.event.StatusListener) Gate.getListeners().get("gate.event.StatusListener");
    if (pListener != null)
        pListener.progressChanged(0);
    startLoadingFrom(url);
    // the actual stream obtained from the URL. We keep a reference to this
    // so we can ensure it gets closed.
    InputStream rawStream = null;
    try {
        long startTime = System.currentTimeMillis();
        // Determine whether the file contains an application serialized in
        // xml
        // format. Otherwise we will assume that it contains native
        // serializations.
        boolean xmlStream = isXmlApplicationFile(url);
        ObjectInputStream ois = null;
        HierarchicalStreamReader reader = null;
        XStream xstream = null;
        // whether serialization is native or xml.
        if (xmlStream) {
            // we don't want to strip the BOM on XML.
            Reader inputReader = new InputStreamReader(rawStream = url.openStream());
            try {
                XMLInputFactory inputFactory = XMLInputFactory.newInstance();
                inputFactory.setProperty(XMLInputFactory.IS_COALESCING, true);
                XMLStreamReader xsr = inputFactory.createXMLStreamReader(url.toExternalForm(), inputReader);
                reader = new StaxReader(new QNameMap(), xsr);
            } catch (XMLStreamException xse) {
                // make sure the stream is closed, on error
                inputReader.close();
                throw new PersistenceException("Error creating reader", xse);
            }
            xstream = new XStream(new StaxDriver(new XStream11NameCoder())) {

                @Override
                protected boolean useXStream11XmlFriendlyMapper() {
                    return true;
                }
            };
            // make XStream load classes through the GATE ClassLoader
            xstream.setClassLoader(Gate.getClassLoader());
            // make the XML stream appear as a normal ObjectInputStream
            ois = xstream.createObjectInputStream(reader);
        } else {
            // use GateAwareObjectInputStream to load classes through the
            // GATE ClassLoader if they can't be loaded through the one
            // ObjectInputStream would normally use
            ois = new GateAwareObjectInputStream(url.openStream());
        }
        Object res = null;
        try {
            // first read the list of creole URLs.
            @SuppressWarnings("unchecked") Iterator<?> urlIter = ((Collection<?>) getTransientRepresentation(ois.readObject())).iterator();
            // and re-register them
            while (urlIter.hasNext()) {
                Object anUrl = urlIter.next();
                try {
                    if (anUrl instanceof URL)
                        Gate.getCreoleRegister().registerPlugin(new Plugin.Directory((URL) anUrl), false);
                    else if (anUrl instanceof Plugin)
                        Gate.getCreoleRegister().registerPlugin((Plugin) anUrl, false);
                } catch (GateException ge) {
                    System.out.println("We've hit an error!");
                    ge.printStackTrace();
                    ge.printStackTrace(Err.getPrintWriter());
                    Err.prln("Could not reload creole directory " + anUrl);
                }
            }
            // now we can read the saved object in the presence of all
            // the right plugins
            res = ois.readObject();
            // ensure a fresh start
            clearCurrentTransients();
            res = getTransientRepresentation(res);
            long endTime = System.currentTimeMillis();
            if (sListener != null)
                sListener.statusChanged("Loading completed in " + NumberFormat.getInstance().format((double) (endTime - startTime) / 1000) + " seconds");
            return res;
        } catch (ResourceInstantiationException rie) {
            if (sListener != null)
                sListener.statusChanged("Failure during instantiation of resources.");
            throw rie;
        } catch (PersistenceException pe) {
            if (sListener != null)
                sListener.statusChanged("Failure during persistence operations.");
            throw pe;
        } catch (Exception ex) {
            if (sListener != null)
                sListener.statusChanged("Loading failed!");
            throw new PersistenceException(ex);
        } finally {
            // make sure the stream gets closed
            if (ois != null)
                ois.close();
            if (reader != null)
                reader.close();
        }
    } finally {
        if (rawStream != null)
            rawStream.close();
        finishedLoading();
        if (pListener != null)
            pListener.processFinished();
    }
}