Example usage for java.net URLConnection connect

List of usage examples for java.net URLConnection connect

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Introduction

In this page you can find the example usage for java.net URLConnection connect.

Prototype

public abstract void connect() throws IOException;

Source Link

Document

Opens a communications link to the resource referenced by this URL, if such a connection has not already been established.

Usage

From source file:org.apache.ojb.broker.metadata.RepositoryPersistor.java

/**
 *
 * TODO: We should re-design the configuration file reading
 *//*from w  w w. jav  a 2s . c o  m*/
private Object buildRepository(String repositoryFileName, Class targetRepository)
        throws MalformedURLException, ParserConfigurationException, SAXException, IOException {
    URL url = buildURL(repositoryFileName);
    /*
    arminw:
    strange, when using 'url.openStream()' argument repository
    could not be parsed
    ipriha:
    parser needs a base url to find referenced entities.
    */
    // InputSource source = new InputSource(url.openStream());

    String pathName = url.toExternalForm();

    log.info("Building repository from :" + pathName);
    InputSource source = new InputSource(pathName);
    URLConnection conn = url.openConnection();
    conn.setUseCaches(false);
    conn.connect();
    InputStream in = conn.getInputStream();
    source.setByteStream(in);
    try {
        return readMetadataFromXML(source, targetRepository);
    } finally {
        try {
            in.close();
        } catch (IOException x) {
            log.warn("unable to close repository input stream [" + x.getMessage() + "]", x);
        }
    }
}

From source file:org.ambraproject.service.search.SolrHttpServiceImpl.java

/**
 * @inheritDoc//  w w w  .  j  a  va  2 s .  c  o m
 */
public Document makeSolrRequestForRss(String queryString) throws SolrException {

    if (solrUrl == null || solrUrl.isEmpty()) {
        setSolrUrl(config.getString(URL_CONFIG_PARAM));
    }

    queryString = "?" + queryString;

    URL url;
    String urlString = solrUrl + queryString;
    log.debug("Making Solr http request to " + urlString);
    try {
        url = new URL(urlString);
    } catch (MalformedURLException e) {
        throw new SolrException("Bad Solr Url: " + urlString, e);
    }

    InputStream urlStream = null;
    Document doc = null;
    try {
        URLConnection connection = url.openConnection();
        connection.setConnectTimeout(CONNECTION_TIMEOUT);
        connection.connect();
        urlStream = connection.getInputStream();
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(true);
        DocumentBuilder builder = factory.newDocumentBuilder();
        doc = builder.parse(urlStream);
    } catch (IOException e) {
        throw new SolrException("Error connecting to the Solr server at " + solrUrl, e);
    } catch (ParserConfigurationException e) {
        throw new SolrException("Error configuring parser xml parser for solr response", e);
    } catch (SAXException e) {
        throw new SolrException("Solr Returned bad XML for url: " + urlString, e);
    } finally {
        //Close the input stream
        if (urlStream != null) {
            try {
                urlStream.close();
            } catch (IOException e) {
                log.error("Error closing url stream to Solr", e);
            }
        }
    }

    return doc;
}

From source file:ubic.basecode.ontology.OntologyLoader.java

/**
 * Load an ontology into memory. Use this type of model when fast access is critical and memory is available.
 * If load from URL fails, attempt to load from disk cache under @cacheName.
 * /*from   w  w  w . java2 s  . co  m*/
 * @param  url
 * @param  spec      e.g. OWL_MEM_TRANS_INF
 * @param  cacheName unique name of this ontology, will be used to load from disk in case of failed url connection
 * @return
 */
public static OntModel loadMemoryModel(String url, OntModelSpec spec, String cacheName) {
    StopWatch timer = new StopWatch();
    timer.start();
    OntModel model = getMemoryModel(url, spec);

    URLConnection urlc = null;
    int tries = 0;
    while (tries < MAX_CONNECTION_TRIES) {
        try {
            urlc = new URL(url).openConnection();
            // help ensure mis-configured web servers aren't causing trouble.
            urlc.setRequestProperty("Accept", "application/rdf+xml");

            try {
                HttpURLConnection c = (HttpURLConnection) urlc;
                c.setInstanceFollowRedirects(true);
            } catch (ClassCastException e) {
                // not via http, using a FileURLConnection.
            }

            if (tries > 0) {
                log.info("Retrying connecting to " + url + " [" + tries + "/" + MAX_CONNECTION_TRIES
                        + " of max tries");
            } else {
                log.info("Connecting to " + url);
            }

            urlc.connect(); // Will error here on bad URL

            if (urlc instanceof HttpURLConnection) {
                String newUrl = urlc.getHeaderField("Location");

                if (StringUtils.isNotBlank(newUrl)) {
                    log.info("Redirect to " + newUrl);
                    urlc = new URL(newUrl).openConnection();
                    // help ensure mis-configured web servers aren't causing trouble.
                    urlc.setRequestProperty("Accept", "application/rdf+xml");
                    urlc.connect();
                }
            }

            break;
        } catch (IOException e) {
            // try to recover.
            log.error(e + " retrying?");
            tries++;
        }
    }

    if (urlc != null) {
        try (InputStream in = urlc.getInputStream();) {
            Reader reader;
            if (cacheName != null) {
                // write tmp to disk
                File tempFile = getTmpDiskCachePath(cacheName);
                if (tempFile == null) {
                    reader = new InputStreamReader(in);
                } else {
                    tempFile.getParentFile().mkdirs();
                    Files.copy(in, tempFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
                    reader = new FileReader(tempFile);
                }

            } else {
                // Skip the cache
                reader = new InputStreamReader(in);
            }

            assert reader != null;
            try (BufferedReader buf = new BufferedReader(reader);) {
                model.read(buf, url);
            }

            log.info("Load model: " + timer.getTime() + "ms");
        } catch (IOException e) {
            log.error(e.getMessage(), e);
        }
    }

    if (cacheName != null) {

        File f = getDiskCachePath(cacheName);
        File tempFile = getTmpDiskCachePath(cacheName);
        File oldFile = getOldDiskCachePath(cacheName);

        if (model.isEmpty()) {
            // Attempt to load from disk cache

            if (f == null) {
                throw new RuntimeException(
                        "Ontology cache directory required to load from disk: ontology.cache.dir");
            }

            if (f.exists() && !f.isDirectory()) {
                try (BufferedReader buf = new BufferedReader(new FileReader(f));) {
                    model.read(buf, url);
                    // We successfully loaded the cached ontology. Copy the loaded ontology to oldFile
                    // so that we don't recreate indices during initialization based on a false change in
                    // the ontology.
                    Files.copy(f.toPath(), oldFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
                    log.info("Load model from disk: " + timer.getTime() + "ms");
                } catch (IOException e) {
                    log.error(e.getMessage(), e);
                    throw new RuntimeException(
                            "Ontology failed load from URL (" + url + ") and disk cache: " + cacheName);
                }
            } else {
                throw new RuntimeException("Ontology failed load from URL (" + url
                        + ") and disk cache does not exist: " + cacheName);
            }

        } else {
            // Model was successfully loaded into memory from URL with given cacheName
            // Save cache to disk (rename temp file)
            log.info("Caching ontology to disk: " + cacheName);
            if (f != null) {
                try {
                    // Need to compare previous to current so instead of overwriting we'll move the old file
                    f.createNewFile();
                    Files.move(f.toPath(), oldFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
                    Files.move(tempFile.toPath(), f.toPath(), StandardCopyOption.REPLACE_EXISTING);
                } catch (IOException e) {
                    log.error(e.getMessage(), e);
                }
            } else {
                log.warn("Ontology cache directory required to save to disk: ontology.cache.dir");
            }
        }

    }

    assert !model.isEmpty();

    return model;
}

From source file:org.codice.ddf.admin.sources.utils.RequestUtils.java

/**
 * Attempts to open a connection to a URL.
 *
 * <p>Possible Error Codes to be returned - {@link
 * org.codice.ddf.admin.common.report.message.DefaultMessages#CANNOT_CONNECT}
 *
 * @param urlField {@link UrlField} containing the URL to connect to
 * @return a {@link Report} containing no messages on success, or containing {@link
 *     org.codice.ddf.admin.api.report.ErrorMessage}s on failure.
 *//*from   ww  w  . j  av  a 2 s  . c o m*/
public Report<Void> endpointIsReachable(UrlField urlField) {
    URLConnection urlConnection = null;
    try {
        urlConnection = new URL(urlField.getValue()).openConnection();
        urlConnection.setConnectTimeout(CLIENT_TIMEOUT_MILLIS);
        urlConnection.connect();
        LOGGER.debug("Successfully reached {}.", urlField);
    } catch (IOException e) {
        LOGGER.debug("Failed to reach {}, returning an error.", urlField, e);
        return Reports.from(cannotConnectError(urlField.getPath()));
    } finally {
        try {
            if (urlConnection != null) {
                urlConnection.getInputStream().close();
            }
        } catch (IOException e) {
            LOGGER.debug("Error closing connection stream.");
        }
    }
    return Reports.emptyReport();
}

From source file:org.ambraproject.service.search.SolrHttpServiceImpl.java

/**
 * @inheritDoc/*from  w ww  .  j av  a  2  s  .  c  o m*/
 */
@Override
public Document makeSolrRequest(Map<String, String> params) throws SolrException {
    if (solrUrl == null || solrUrl.isEmpty()) {
        setSolrUrl(config.getString(URL_CONFIG_PARAM));
    }

    //make sure the return type is xml
    if (!params.keySet().contains(RETURN_TYPE_PARAM) || !params.get(RETURN_TYPE_PARAM).equals(XML)) {
        params.put(RETURN_TYPE_PARAM, XML);
    }
    //make sure that we include a 'q' parameter
    if (!params.keySet().contains(Q_PARAM)) {
        params.put(Q_PARAM, NO_FILTER);
    }

    String queryString = "?";
    for (String param : params.keySet()) {
        String value = params.get(param);
        if (queryString.length() > 1) {
            queryString += "&";
        }
        queryString += (cleanInput(param) + "=" + cleanInput(value));
    }

    URL url;
    String urlString = solrUrl + queryString;
    log.debug("Making Solr http request to " + urlString);
    try {
        url = new URL(urlString);
    } catch (MalformedURLException e) {
        throw new SolrException("Bad Solr Url: " + urlString, e);
    }

    InputStream urlStream = null;
    Document doc = null;
    try {
        URLConnection connection = url.openConnection();
        connection.setConnectTimeout(CONNECTION_TIMEOUT);
        connection.connect();
        urlStream = connection.getInputStream();
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(true);
        DocumentBuilder builder = factory.newDocumentBuilder();
        doc = builder.parse(urlStream);
    } catch (IOException e) {
        throw new SolrException("Error connecting to the Solr server at " + solrUrl, e);
    } catch (ParserConfigurationException e) {
        throw new SolrException("Error configuring parser xml parser for solr response", e);
    } catch (SAXException e) {
        throw new SolrException("Solr Returned bad XML for url: " + urlString, e);
    } finally {
        //Close the input stream
        if (urlStream != null) {
            try {
                urlStream.close();
            } catch (IOException e) {
                log.error("Error closing url stream to Solr", e);
            }
        }
    }

    return doc;
}

From source file:org.shredzone.commons.gravatar.impl.GravatarServiceImpl.java

/**
 * Fetches a Gravatar icon from the server and stores it in the given {@link File}.
 *
 * @param url//from   w  ww  .java 2s. c  om
 *            Gravatar URL to fetch
 * @param file
 *            {@link File} to store the icon to
 */
private void fetchGravatar(URL url, File file) throws IOException {
    limitUpstreamRequests();

    URLConnection conn = url.openConnection();
    conn.setConnectTimeout(TIMEOUT);
    conn.setReadTimeout(TIMEOUT);

    if (file.exists()) {
        conn.setIfModifiedSince(file.lastModified());
    }

    conn.connect();

    long lastModified = conn.getLastModified();
    if (lastModified > 0L && lastModified <= file.lastModified()) {
        // Cache file exists and is unchanged
        if (log.isDebugEnabled()) {
            log.debug("Cached Gravatar is still good: {}", url);
        }

        file.setLastModified(System.currentTimeMillis()); // touch
        return;
    }

    try (InputStream in = conn.getInputStream(); OutputStream out = new FileOutputStream(file)) {
        byte[] buffer = new byte[8192];
        int total = 0;
        int len;

        while ((len = in.read(buffer)) >= 0) {
            out.write(buffer, 0, len);
            total += len;
            if (total > MAX_GRAVATAR_SIZE) {
                log.warn("Gravatar exceeded maximum size: {}", url);
                break;
            }
        }

        out.flush();

        if (log.isDebugEnabled()) {
            log.debug("Downloaded Gravatar: {}", url);
        }
    }
}

From source file:com.wallabystreet.kinjo.common.transport.protocol.jxta.JXTAWebServiceHandler.java

public void invoke(MessageContext messageContext) throws AxisFault {

    // create and open a connection to the endpoint peer
    String target = messageContext.getStrProp(MessageContext.TRANS_URL);
    URL u = null;//from  w  w  w  . j  a v  a  2s . co  m
    try {
        u = new URL(target);
    } catch (MalformedURLException e) {
        ; // do nothing here
    }

    URLConnection c = null;
    try {
        c = u.openConnection();
    } catch (IOException e) {
        log.error("could not create connection", e);
        throw AxisFault.makeFault(e);
    }

    JxtaBiDiPipe pipe = null;
    try {
        c.connect();
        pipe = ((JXTAURLConnection) c).getConnectionPipe();
    } catch (IOException e) {
        log.error("could not connect", e);
        throw AxisFault.makeFault(e);
    }

    // extract the SOAP request from the message context
    net.jxta.endpoint.Message transportMessage = new net.jxta.endpoint.Message();

    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    try {
        messageContext.getRequestMessage().writeTo(baos);
    } catch (Exception e) {
        log.error("could not serialize message", e);
        throw AxisFault.makeFault(e);
    }

    // wrap the SOAP request into a JXTA transport message
    ByteArrayMessageElement bame = new ByteArrayMessageElement("message", null, baos.toByteArray(), null);
    transportMessage.addMessageElement(bame);

    try {
        // send the message over the connection pipe
        pipe.sendMessage(transportMessage);
    } catch (IOException e) {
        log.error("could not send message", e);
        throw AxisFault.makeFault(e);
    }

    // reset the transport message and wait for the SOAP response
    transportMessage = null;
    try {
        /*
         * XXX: At the moment, we wait forever (until the result message
         * arrives, that is) here. This seems to be a bad idea, since the
         * response message might take ages to arrive. Therefore, a timeout
         * should be introduced here.
         */
        transportMessage = pipe.getMessage(0);
    } catch (InterruptedException e) {
        log.error("interrupt occured during getMessage()", e);
        throw AxisFault.makeFault(e);
    }

    // unwrap the SOAP response
    ByteArrayMessageElement msgString = (ByteArrayMessageElement) transportMessage.getMessageElement("message");
    org.apache.axis.Message responseMessage = new org.apache.axis.Message(msgString.toString());

    // store the SOAP response in the message context
    messageContext.setResponseMessage(responseMessage);
}

From source file:ubic.gemma.loader.expression.geo.service.GeoBrowser.java

/**
 * Performs an E-utilities query of the GEO database with the given searchTerms.  
 * Returns at most pageSize records (if found) starting at record #start.
 * /* w ww . jav  a2  s . c  o m*/
 * @param start
 * @param pageSize
 * @param searchTerms
 * @return list of GeoRecords
 * @throws IOException
 * @throws RunTimeException
 */
public List<GeoRecord> getGeoRecordsBySearchTerm(String searchTerms, int start, int pageSize)
        throws IOException, RuntimeException {

    List<GeoRecord> records = new ArrayList<GeoRecord>();

    try {
        URL searchUrl = new URL(
                ESEARCH + searchTerms + "&retstart=" + start + "&retmax=" + pageSize + "&usehistory=y");

        URLConnection conn = searchUrl.openConnection();
        conn.connect();
        InputStream is = conn.getInputStream();

        docFactory.setIgnoringComments(true);
        docFactory.setValidating(false);

        DocumentBuilder builder = docFactory.newDocumentBuilder();
        Document searchDocument = builder.parse(is);

        NodeList countNode = searchDocument.getElementsByTagName("Count");
        Node countEl = countNode.item(0);

        int count = 0;
        try {
            count = Integer.parseInt(XMLUtils.getTextValue((Element) countEl));
        } catch (NumberFormatException e) {
            throw new IOException("Could not parse count from: " + searchUrl);
        }

        if (count == 0)
            throw new IOException("Got no records from: " + searchUrl);

        NodeList qnode = searchDocument.getElementsByTagName("QueryKey");

        Element queryIdEl = (Element) qnode.item(0);

        NodeList cknode = searchDocument.getElementsByTagName("WebEnv");
        Element cookieEl = (Element) cknode.item(0);

        String queryId = XMLUtils.getTextValue(queryIdEl);
        String cookie = XMLUtils.getTextValue(cookieEl);

        URL fetchUrl = new URL(EFETCH + "&mode=mode.text" + "&query_key=" + queryId + "&retstart=" + start
                + "&retmax=" + pageSize + "&WebEnv=" + cookie);

        conn = fetchUrl.openConnection();
        conn.connect();
        is = conn.getInputStream();

        Document summaryDocument = builder.parse(is);

        XPathFactory xFactory = XPathFactory.newInstance();
        XPath xpath = xFactory.newXPath();

        // Get relevant data from the XML file
        xaccession = xpath.compile("//DocSum/Item[@Name='GSE']");
        xtitle = xpath.compile("//DocSum/Item[@Name='title']");
        xnumSamples = xpath.compile("//DocSum/Item[@Name='n_samples']");
        xreleaseDate = xpath.compile("//DocSum/Item[@Name='PDAT']");
        xorganisms = xpath.compile("//DocSum/Item[@Name='taxon']");

        Object accessions = xaccession.evaluate(summaryDocument, XPathConstants.NODESET);
        NodeList accNodes = (NodeList) accessions;

        Object titles = xtitle.evaluate(summaryDocument, XPathConstants.NODESET);
        NodeList titleNodes = (NodeList) titles;

        Object samples = xnumSamples.evaluate(summaryDocument, XPathConstants.NODESET);
        NodeList sampleNodes = (NodeList) samples;

        Object dates = xreleaseDate.evaluate(summaryDocument, XPathConstants.NODESET);
        NodeList dateNodes = (NodeList) dates;

        Object organisms = xorganisms.evaluate(summaryDocument, XPathConstants.NODESET);
        NodeList orgnNodes = (NodeList) organisms;

        // Create GeoRecords using information parsed from XML file 
        for (int i = 0; i < accNodes.getLength(); i++) {

            GeoRecord record = new GeoRecord();

            record.setGeoAccession("GSE" + accNodes.item(i).getTextContent());

            record.setTitle(titleNodes.item(i).getTextContent());

            record.setNumSamples(Integer.parseInt(sampleNodes.item(i).getTextContent()));

            Date date = DateUtil.convertStringToDate("yyyy/MM/dd", dateNodes.item(i).getTextContent());
            record.setReleaseDate(date);

            record.setOrganisms(getTaxonCollection(orgnNodes.item(i).getTextContent()));

            records.add(record);
        }

    } catch (MalformedURLException e) {
        throw new RuntimeException(e);
    } catch (ParserConfigurationException e) {
        throw new RuntimeException(e);
    } catch (SAXException e) {
        throw new RuntimeException(e);
    } catch (XPathException e) {
        throw new RuntimeException(e);
    } catch (ParseException e) {
        throw new RuntimeException(e);
    }

    if (records.isEmpty()) {
        log.warn("No records obtained");
    }

    return records;

}

From source file:ResourceServlet.java

public void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

    //get web.xml for display by a servlet
    String file = "/WEB-INF/web.xml";

    URL url = null;/*from   w w w .  ja va 2 s  .  c om*/
    URLConnection urlConn = null;
    PrintWriter out = null;
    BufferedInputStream buf = null;
    try {
        out = response.getWriter();
        url = getServletContext().getResource(file);
        //set response header
        response.setContentType("text/xml");

        urlConn = url.openConnection();
        //establish connection with URL presenting web.xml
        urlConn.connect();
        buf = new BufferedInputStream(urlConn.getInputStream());
        int readBytes = 0;
        while ((readBytes = buf.read()) != -1)
            out.write(readBytes);
    } catch (MalformedURLException mue) {
        throw new ServletException(mue.getMessage());
    } catch (IOException ioe) {
        throw new ServletException(ioe.getMessage());
    } finally {
        if (out != null)
            out.close();
        if (buf != null)
            buf.close();
    }
}

From source file:ome.system.UpgradeCheck.java

/**
 * If the {@link #url} has been set to null or the empty string, then no
 * upgrade check will be performed (silently). If however the string is an
 * invalid URL, a warning will be printed.
 * //from   w w w.  java 2s.c  o  m
 * This method should <em>never</em> throw an exception.
 */
public void run() {

    // If null or empty, the upgrade check is disabled.
    if (url == null || url.length() == 0) {
        return; // EARLY EXIT!
    }

    StringBuilder query = new StringBuilder();
    try {
        query.append(url);
        query.append("?version=");
        query.append(URLEncoder.encode(version, "UTF-8"));
        query.append(";os.name=");
        query.append(URLEncoder.encode(System.getProperty("os.name"), "UTF-8"));
        query.append(";os.arch=");
        query.append(URLEncoder.encode(System.getProperty("os.arch"), "UTF-8"));
        query.append(";os.version=");
        query.append(URLEncoder.encode(System.getProperty("os.version"), "UTF-8"));
        query.append(";java.runtime.version=");
        query.append(URLEncoder.encode(System.getProperty("java.runtime.version"), "UTF-8"));
        query.append(";java.vm.vendor=");
        query.append(URLEncoder.encode(System.getProperty("java.vm.vendor"), "UTF-8"));
    } catch (UnsupportedEncodingException uee) {
        // Internal issue
        set(null, uee);
        return;
    }

    URL _url;
    try {
        _url = new URL(query.toString());
    } catch (Exception e) {
        set(null, e);
        log.error("Invalid URL: " + query.toString());
        return;
    }

    BufferedInputStream bufIn = null;
    try {
        URLConnection conn = _url.openConnection();
        conn.setUseCaches(false);
        conn.addRequestProperty("User-Agent", agent);
        conn.setConnectTimeout(timeout);
        conn.setReadTimeout(timeout);
        conn.connect();

        log.debug("Attempting to connect to " + query);

        InputStream in = conn.getInputStream();
        bufIn = new BufferedInputStream(in);

        StringBuilder sb = new StringBuilder();
        while (true) {
            int data = bufIn.read();
            if (data == -1) {
                break;
            } else {
                sb.append((char) data);
            }
        }
        String result = sb.toString();
        if (result.length() == 0) {
            log.info("no update needed");
            set(null, null);
        } else {
            log.warn("UPGRADE AVAILABLE:" + result);
            set(result, null);
        }
    } catch (UnknownHostException uhe) {
        log.error("Unknown host:" + url);
        set(null, uhe);
    } catch (IOException ioe) {
        log.error(String.format("Error reading from url: %s \"%s\"", query, ioe.getMessage()));
        set(null, ioe);
    } catch (Exception ex) {
        log.error("Unknown exception thrown on UpgradeCheck", ex);
        set(null, ex);
    } finally {
        Utils.closeQuietly(bufIn);
    }
}