Example usage for java.net HttpURLConnection HTTP

Introduction

In this page you can find the example usage for java.net HttpURLConnection HTTP_UNAVAILABLE.

Prototype

int HTTP_UNAVAILABLE

To view the source code for java.net HttpURLConnection HTTP_UNAVAILABLE.

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Document

HTTP Status-Code 503: Service Unavailable.

Usage

From source file:com.google.apphosting.vmruntime.VmApiProxyDelegateTest.java

private void callDelegateWithConnectionError(boolean sync, ApiProxyException expectedException)
        throws Exception {
    HttpClient mockClient = createMockHttpClient();
    createMockHttpResponse(new byte[0], HttpURLConnection.HTTP_UNAVAILABLE);
    when(mockClient.execute(Mockito.any(HttpUriRequest.class), Mockito.any(HttpContext.class)))
            .thenThrow(new IOException("Connection refused"));

    VmApiProxyDelegate delegate = new VmApiProxyDelegate(mockClient);
    VmApiProxyEnvironment environment = createMockEnvironment();

    byte[] requestData = new byte[] { 0, 1, 2, 3, 4, 5 };
    byte[] result = null;
    final Double timeoutInSeconds = 10.0;

    if (sync) {// w  w  w .  ja v  a2s  .c om
        try {
            environment.getAttributes().put(VmApiProxyDelegate.API_DEADLINE_KEY, timeoutInSeconds);
            result = delegate.makeSyncCall(environment, TEST_PACKAGE_NAME, TEST_METHOD_NAME, requestData);
            fail();
        } catch (ApiProxyException exception) {
            assertEquals(expectedException.getClass(), exception.getClass());
        }
    } else {
        try {
            ApiConfig apiConfig = new ApiConfig();
            apiConfig.setDeadlineInSeconds(timeoutInSeconds);
            result = delegate
                    .makeAsyncCall(environment, TEST_PACKAGE_NAME, TEST_METHOD_NAME, requestData, apiConfig)
                    .get();
            fail();
        } catch (ExecutionException exception) {
            // ExecutionException is expected, and make sure the cause is expected as well.
            assertEquals(expectedException.getClass(), exception.getCause().getClass());
        }
    }
    assertNull(result);
}

From source file:org.oclc.oai.harvester2.verb.HarvesterVerb.java

/**
 * Preforms the OAI request, recovering from typical XML error
 *
 * @author nfreire Nuno Freire / Gilberto Pedrosa
 * @param requestURL/*w  ww  .  j  a v a 2s.  c  o m*/
 * @throws IOException
 * @throws ParserConfigurationException
 * @throws SAXException
 * @throws TransformerException
 */
private void harvest(String requestURL)
        throws IOException, ParserConfigurationException, SAXException, TransformerException {
    this.requestURL = requestURL;
    logger.debug("requestURL=" + requestURL);
    InputStream in;
    URL url = new URL(requestURL);
    HttpURLConnection con;
    int responseCode;
    do {
        con = (HttpURLConnection) url.openConnection();
        con.setConnectTimeout(30000);
        con.setReadTimeout(600000);

        if (con.getAllowUserInteraction()) {
            con.setRequestProperty("User-Agent", "OAIHarvester/2.0");
            con.setRequestProperty("Accept-Encoding", "compress, gzip, identify");
        }
        try {
            responseCode = con.getResponseCode();
            logger.debug("responseCode=" + responseCode);
        } catch (FileNotFoundException e) {
            // assume it's a 503 response
            logger.error(requestURL, e);
            responseCode = HttpURLConnection.HTTP_UNAVAILABLE;
        }

        if (responseCode == HttpURLConnection.HTTP_UNAVAILABLE) {
            long retrySeconds = con.getHeaderFieldInt("Retry-After", -1);
            if (retrySeconds == -1) {
                long now = (new Date()).getTime();
                long retryDate = con.getHeaderFieldDate("Retry-After", now);
                retrySeconds = retryDate - now;
            }
            if (retrySeconds == 0) { // Apparently, it's a bad URL
                throw new FileNotFoundException("Bad URL?");
            }
            logger.warn("Server response: Retry-After=" + retrySeconds);
            if (retrySeconds > 0) {
                try {
                    Thread.sleep(retrySeconds * 1000);
                } catch (InterruptedException ex) {
                    ex.printStackTrace();
                }
            }
        }
    } while (responseCode == HttpURLConnection.HTTP_UNAVAILABLE);
    String contentEncoding = con.getHeaderField("Content-Encoding");
    logger.debug("contentEncoding=" + contentEncoding);
    if ("compress".equals(contentEncoding)) {
        ZipInputStream zis = new ZipInputStream(con.getInputStream());
        zis.getNextEntry();
        in = zis;
    } else if ("gzip".equals(contentEncoding)) {
        in = new GZIPInputStream(con.getInputStream());
    } else if ("deflate".equals(contentEncoding)) {
        in = new InflaterInputStream(con.getInputStream());
    } else {
        in = con.getInputStream();
    }

    byte[] inputBytes = IOUtils.toByteArray(in);
    InputSource data = new InputSource(new ByteArrayInputStream(inputBytes));

    Thread t = Thread.currentThread();
    DocumentBuilder builder = (DocumentBuilder) builderMap.get(t);
    if (builder == null) {
        builder = factory.newDocumentBuilder();
        builderMap.put(t, builder);
    }
    try {
        doc = builder.parse(data);
    } catch (SAXException e) {
        try {
            //Here we can try to recover the xml from known typical problems

            //Recover from invalid characters
            //we assume this is UTF-8...
            String xmlString = new String(inputBytes, "UTF-8");
            xmlString = XmlUtil.removeInvalidXMLCharacters(xmlString);

            data = new InputSource(new ByteArrayInputStream(xmlString.getBytes("UTF-8")));
            doc = builder.parse(data);
        } catch (Exception e2) {
            //the recovered version did not work either. Throw the original exception
            throw e;
        }
    } catch (IOException e3) {
        System.out.println("e = " + e3.getMessage());
    } catch (Exception e4) {
        System.out.println("e = " + e4.getMessage());
    }

    StringTokenizer tokenizer = new StringTokenizer(getSingleString("/*/@xsi:schemaLocation"), " ");
    StringBuffer sb = new StringBuffer();
    while (tokenizer.hasMoreTokens()) {
        if (sb.length() > 0)
            sb.append(" ");
        sb.append(tokenizer.nextToken());
    }
    this.schemaLocation = sb.toString();
    this.defaultNamespace = getDocument().getDocumentElement().getNamespaceURI();
}

From source file:org.oclc.oai.harvester.verb.HarvesterVerb.java

/**
 * Performs the OAI request, recovering from typical XML error
 * //from  w  w w. j  a  va2  s .co  m
 * @author nfreire Nuno Freire / Gilberto Pedrosa
 * @param requestURL
 * @throws IOException
 * @throws ParserConfigurationException
 * @throws SAXException
 * @throws TransformerException
 */
private void harvest(String requestURL)
        throws IOException, ParserConfigurationException, SAXException, TransformerException {
    this.requestURL = requestURL;
    logger.debug("requestURL=" + requestURL);
    InputStream in;
    URL url = new URL(requestURL);
    HttpURLConnection con;
    int responseCode;
    do {
        con = (HttpURLConnection) url.openConnection();
        con.setConnectTimeout(30000);
        con.setReadTimeout(600000);

        if (con.getAllowUserInteraction()) {
            con.setRequestProperty("User-Agent", "OAIHarvester/2.0");
            con.setRequestProperty("Accept-Encoding", "compress, gzip, identify");
        }
        try {
            responseCode = con.getResponseCode();
            logger.debug("responseCode=" + responseCode);
        } catch (FileNotFoundException e) {
            // assume it's a 503 response
            logger.error(requestURL, e);
            responseCode = HttpURLConnection.HTTP_UNAVAILABLE;
        }

        if (responseCode == HttpURLConnection.HTTP_UNAVAILABLE) {
            long retrySeconds = con.getHeaderFieldInt("Retry-After", -1);
            if (retrySeconds == -1) {
                long now = (new Date()).getTime();
                long retryDate = con.getHeaderFieldDate("Retry-After", now);
                retrySeconds = retryDate - now;
            }
            if (retrySeconds == 0) { // Apparently, it's a bad URL
                throw new FileNotFoundException("Bad URL?");
            }
            logger.warn("Server response: Retry-After=" + retrySeconds);
            if (retrySeconds > 0) {
                try {
                    Thread.sleep(retrySeconds * 1000);
                } catch (InterruptedException ex) {
                    ex.printStackTrace();
                }
            }
        }
    } while (responseCode == HttpURLConnection.HTTP_UNAVAILABLE);
    String contentEncoding = con.getHeaderField("Content-Encoding");
    logger.debug("contentEncoding=" + contentEncoding);
    if ("compress".equals(contentEncoding)) {
        ZipInputStream zis = new ZipInputStream(con.getInputStream());
        zis.getNextEntry();
        in = zis;
    } else if ("gzip".equals(contentEncoding)) {
        in = new GZIPInputStream(con.getInputStream());
    } else if ("deflate".equals(contentEncoding)) {
        in = new InflaterInputStream(con.getInputStream());
    } else {
        in = con.getInputStream();
    }

    byte[] inputBytes = IOUtils.toByteArray(in);
    InputSource data = new InputSource(new ByteArrayInputStream(inputBytes));

    Thread t = Thread.currentThread();
    DocumentBuilder builder = builderMap.get(t);
    if (builder == null) {
        builder = factory.newDocumentBuilder();
        builderMap.put(t, builder);
    }
    try {
        doc = builder.parse(data);
    } catch (SAXException e) {
        try {
            //Here we can try to recover the xml from known typical problems

            //Recover from invalid characters
            //we assume this is UTF-8...
            String xmlString = new String(inputBytes, "UTF-8");
            xmlString = XmlUtil.removeInvalidXMLCharacters(xmlString);

            data = new InputSource(new ByteArrayInputStream(xmlString.getBytes("UTF-8")));
            doc = builder.parse(data);
        } catch (Exception e2) {
            //the recovered version did not work either. Throw the original exception
            throw e;
        }
    } catch (IOException e3) {
        System.out.println("e = " + e3.getMessage());
    } catch (Exception e4) {
        System.out.println("e = " + e4.getMessage());
    }

    StringTokenizer tokenizer = new StringTokenizer(getSingleString("/*/@xsi:schemaLocation"), " ");
    StringBuffer sb = new StringBuffer();
    while (tokenizer.hasMoreTokens()) {
        if (sb.length() > 0)
            sb.append(" ");
        sb.append(tokenizer.nextToken());
    }
    this.schemaLocation = sb.toString();
    this.defaultNamespace = getDocument().getDocumentElement().getNamespaceURI();
}

From source file:com.scvngr.levelup.core.net.LevelUpResponse.java

/**
 * Maps an {@link LevelUpStatus} to an HTTP status code from the response.
 *
 * @param statusCode the HTTP status code from the response.
 * @param serverHeader the value of the Server HTTP header; this is used to validate whether the
 *        response is coming from the LevelUp Platform server or a backup/reverse-proxy.
 * @return {@link LevelUpStatus} describing the status code.
 *///  www. j a va  2 s .  c o m
@NonNull
@VisibleForTesting(visibility = Visibility.PRIVATE)
/* package */static LevelUpStatus mapStatus(final int statusCode, @Nullable final String serverHeader) {
    final boolean fromLevelUpPlatform = HTTP_HEADER_VALUE_SERVER.equals(serverHeader);
    final LevelUpStatus status;

    if (statusCode >= AbstractResponse.STATUS_CODE_SUCCESS_MIN_INCLUSIVE
            && statusCode < AbstractResponse.STATUS_CODE_SUCCESS_MAX_EXCLUSIVE) {
        // A 2xx status code is OK.
        status = LevelUpStatus.OK;
    } else if (HttpURLConnection.HTTP_NOT_IMPLEMENTED == statusCode && fromLevelUpPlatform) {
        /*
         * The API treats a 501 response as a requirement for the client to be upgraded.
         * However, in failover etc. this response should be ignored since it may have a
         * different meaning coming from other servers.
         */
        status = LevelUpStatus.UPGRADE;
    } else if (HttpURLConnection.HTTP_UNAUTHORIZED == statusCode && fromLevelUpPlatform) {
        /*
         * The API treats a 401 response as a notice that the user needs a new access token, and
         * should be logged out. However, if a reverse-proxy or backup server is sending the
         * response, this should be ignored since it may have a different meaning coming from
         * other servers.
         */
        status = LevelUpStatus.LOGIN_REQUIRED;
    } else if (HttpURLConnection.HTTP_NOT_FOUND == statusCode && fromLevelUpPlatform) {
        /*
         * Some endpoints (like PaymentToken) have special meanings for 404s, but in failover
         * they may just indicate a partially-functioning service and should be treated as
         * generic network errors.
         */
        status = LevelUpStatus.ERROR_NOT_FOUND;
    } else if (HttpURLConnection.HTTP_UNAVAILABLE == statusCode) {
        // LevelUp is down for maintenance (applicable even if the Server header differs).
        status = LevelUpStatus.ERROR_MAINTENANCE;
    } else {
        // All other response codes are server errors.
        status = LevelUpStatus.ERROR_SERVER;
    }

    return status;
}

From source file:org.eclipse.hono.client.impl.HonoClientImpl.java

private void reconnect(final Throwable connectionFailureCause,
        final Handler<AsyncResult<HonoClient>> connectionHandler,
        final Handler<ProtonConnection> disconnectHandler) {

    if (shuttingDown.get()) {
        // no need to try to re-connect
        connectionHandler.handle(Future.failedFuture(new IllegalStateException("client is shut down")));
    } else if (clientOptions.getReconnectAttempts() - reconnectAttempts.get() == 0) {
        reconnectAttempts = new AtomicInteger(0);
        LOG.debug("max number of attempts [{}] to re-connect to peer [{}:{}] have been made, giving up",
                clientOptions.getReconnectAttempts(), connectionFactory.getHost(), connectionFactory.getPort());
        if (connectionFailureCause == null) {
            connectionHandler.handle(Future.failedFuture(
                    new ServerErrorException(HttpURLConnection.HTTP_UNAVAILABLE, "failed to connect")));
        } else {/*  w w  w.j a  v a  2 s . c o m*/
            connectionHandler
                    .handle(Future.failedFuture(new ServerErrorException(HttpURLConnection.HTTP_UNAVAILABLE,
                            "failed to connect", connectionFailureCause)));
        }
    } else {
        LOG.trace("scheduling attempt to re-connect ...");
        reconnectAttempts.getAndIncrement();
        // give Vert.x some time to clean up NetClient
        vertx.setTimer(clientOptions.getReconnectInterval(), tid -> {
            LOG.debug("starting attempt [#{}] to re-connect to server [{}:{}]", reconnectAttempts.get(),
                    connectionFactory.getHost(), connectionFactory.getPort());
            connect(clientOptions, connectionHandler, disconnectHandler);
        });
    }
}

From source file:org.openstreetmap.josm.data.cache.JCSCachedTileLoaderJob.java

/**
 * @return true if object was successfully downloaded, false, if there was a loading failure
 *//*  ww  w  . j  a v  a  2  s  .c  o m*/
private boolean loadObject() {
    if (attributes == null) {
        attributes = new CacheEntryAttributes();
    }
    try {
        // if we have object in cache, and host doesn't support If-Modified-Since nor If-None-Match
        // then just use HEAD request and check returned values
        if (isObjectLoadable() && Boolean.TRUE.equals(useHead.get(getServerKey())) && isCacheValidUsingHead()) {
            LOG.log(Level.FINE, "JCS - cache entry verified using HEAD request: {0}", getUrl());
            return true;
        }

        LOG.log(Level.FINE, "JCS - starting HttpClient GET request for URL: {0}", getUrl());
        final HttpClient request = getRequest("GET", true);

        if (isObjectLoadable() && (now - attributes.getLastModification()) <= ABSOLUTE_EXPIRE_TIME_LIMIT) {
            request.setIfModifiedSince(attributes.getLastModification());
        }
        if (isObjectLoadable() && attributes.getEtag() != null) {
            request.setHeader("If-None-Match", attributes.getEtag());
        }

        final HttpClient.Response urlConn = request.connect();

        if (urlConn.getResponseCode() == 304) {
            // If isModifiedSince or If-None-Match has been set
            // and the server answers with a HTTP 304 = "Not Modified"
            LOG.log(Level.FINE, "JCS - If-Modified-Since/ETag test: local version is up to date: {0}",
                    getUrl());
            return true;
        } else if (isObjectLoadable() // we have an object in cache, but we haven't received 304 response code
                && ((attributes.getEtag() != null
                        && attributes.getEtag().equals(urlConn.getHeaderField("ETag")))
                        || attributes.getLastModification() == urlConn.getLastModified())) {
            // we sent ETag or If-Modified-Since, but didn't get 304 response code
            // for further requests - use HEAD
            String serverKey = getServerKey();
            LOG.log(Level.INFO,
                    "JCS - Host: {0} found not to return 304 codes for If-Modified-Since or If-None-Match headers",
                    serverKey);
            useHead.put(serverKey, Boolean.TRUE);
        }

        attributes = parseHeaders(urlConn);

        for (int i = 0; i < 5; ++i) {
            if (urlConn.getResponseCode() == HttpURLConnection.HTTP_UNAVAILABLE) {
                Thread.sleep(5000L + new SecureRandom().nextInt(5000));
                continue;
            }

            attributes.setResponseCode(urlConn.getResponseCode());
            byte[] raw;
            if (urlConn.getResponseCode() == HttpURLConnection.HTTP_OK) {
                raw = Utils.readBytesFromStream(urlConn.getContent());
            } else {
                raw = new byte[] {};
            }

            if (isResponseLoadable(urlConn.getHeaderFields(), urlConn.getResponseCode(), raw)) {
                // we need to check cacheEmpty, so for cases, when data is returned, but we want to store
                // as empty (eg. empty tile images) to save some space
                cacheData = createCacheEntry(raw);
                cache.put(getCacheKey(), cacheData, attributes);
                LOG.log(Level.FINE, "JCS - downloaded key: {0}, length: {1}, url: {2}",
                        new Object[] { getCacheKey(), raw.length, getUrl() });
                return true;
            } else if (cacheAsEmpty()) {
                cacheData = createCacheEntry(new byte[] {});
                cache.put(getCacheKey(), cacheData, attributes);
                LOG.log(Level.FINE, "JCS - Caching empty object {0}", getUrl());
                return true;
            } else {
                LOG.log(Level.FINE, "JCS - failure during load - reponse is not loadable nor cached as empty");
                return false;
            }
        }
    } catch (FileNotFoundException e) {
        LOG.log(Level.FINE, "JCS - Caching empty object as server returned 404 for: {0}", getUrlNoException());
        attributes.setResponseCode(404);
        attributes.setError(e);
        boolean doCache = isResponseLoadable(null, 404, null) || cacheAsEmpty();
        if (doCache) {
            cacheData = createCacheEntry(new byte[] {});
            cache.put(getCacheKey(), cacheData, attributes);
        }
        return doCache;
    } catch (IOException e) {
        LOG.log(Level.FINE, "JCS - IOExecption during communication with server for: {0}", getUrlNoException());
        if (isObjectLoadable()) {
            return true;
        } else {
            attributes.setError(e);
            attributes.setResponseCode(599); // set dummy error code, greater than 500 so it will be not cached
            return false;
        }

    } catch (InterruptedException e) {
        attributes.setError(e);
        LOG.log(Level.WARNING, "JCS - Exception during download {0}", getUrlNoException());
        Logging.warn(e);
        Thread.currentThread().interrupt();
    }
    LOG.log(Level.WARNING, "JCS - Silent failure during download: {0}", getUrlNoException());
    return false;
}

From source file:org.eclipse.hono.client.impl.HonoClientImpl.java

Future<MessageSender> getOrCreateSender(final String key,
        final Supplier<Future<MessageSender>> newSenderSupplier) {

    final Future<MessageSender> result = Future.future();

    context.runOnContext(get -> {/*from  ww w.  j  a v a  2  s.  co  m*/
        final MessageSender sender = activeSenders.get(key);
        if (sender != null && sender.isOpen()) {
            LOG.debug("reusing existing message sender [target: {}, credit: {}]", key, sender.getCredit());
            result.complete(sender);
        } else if (!creationLocks.computeIfAbsent(key, k -> Boolean.FALSE)) {
            // register a handler to be notified if the underlying connection to the server fails
            // so that we can fail the result handler passed in
            final Handler<Void> connectionFailureHandler = connectionLost -> {
                // remove lock so that next attempt to open a sender doesn't fail
                creationLocks.remove(key);
                result.tryFail(new ServerErrorException(HttpURLConnection.HTTP_UNAVAILABLE,
                        "no connection to service"));
            };
            creationRequests.add(connectionFailureHandler);
            creationLocks.put(key, Boolean.TRUE);
            LOG.debug("creating new message sender for {}", key);

            newSenderSupplier.get().setHandler(creationAttempt -> {
                creationLocks.remove(key);
                creationRequests.remove(connectionFailureHandler);
                if (creationAttempt.succeeded()) {
                    MessageSender newSender = creationAttempt.result();
                    LOG.debug("successfully created new message sender for {}", key);
                    activeSenders.put(key, newSender);
                    result.tryComplete(newSender);
                } else {
                    LOG.debug("failed to create new message sender for {}", key, creationAttempt.cause());
                    activeSenders.remove(key);
                    result.tryFail(creationAttempt.cause());
                }
            });

        } else {
            LOG.debug("already trying to create a message sender for {}", key);
            result.fail(
                    new ServerErrorException(HttpURLConnection.HTTP_UNAVAILABLE, "no connection to service"));
        }
    });
    return result;
}

From source file:net.myrrix.client.ClientRecommender.java

@Override
public float[] estimatePreferences(long userID, long... itemIDs) throws TasteException {
    StringBuilder urlPath = new StringBuilder();
    urlPath.append("/estimate/");
    urlPath.append(userID);// w w  w  .j  av a 2 s. c  om
    for (long itemID : itemIDs) {
        urlPath.append('/').append(itemID);
    }

    TasteException savedException = null;
    for (HostAndPort replica : choosePartitionAndReplicas(userID)) {
        HttpURLConnection connection = null;
        try {
            connection = buildConnectionToReplica(replica, urlPath.toString(), "GET");
            switch (connection.getResponseCode()) {
            case HttpURLConnection.HTTP_OK:
                BufferedReader reader = IOUtils.bufferStream(connection.getInputStream());
                try {
                    float[] result = new float[itemIDs.length];
                    for (int i = 0; i < itemIDs.length; i++) {
                        result[i] = LangUtils.parseFloat(reader.readLine());
                    }
                    return result;
                } finally {
                    reader.close();
                }
            case HttpURLConnection.HTTP_UNAVAILABLE:
                throw new NotReadyException();
            default:
                throw new TasteException(connection.getResponseCode() + " " + connection.getResponseMessage());
            }
        } catch (TasteException te) {
            log.info("Can't access {} at {}: ({})", urlPath, replica, te.toString());
            savedException = te;
        } catch (IOException ioe) {
            log.info("Can't access {} at {}: ({})", urlPath, replica, ioe.toString());
            savedException = new TasteException(ioe);
        } finally {
            if (connection != null) {
                connection.disconnect();
            }
        }
    }
    throw savedException;
}

From source file:net.myrrix.client.ClientRecommender.java

public float estimateForAnonymous(long toItemID, long[] itemIDs, float[] values, Long contextUserID)
        throws TasteException {
    Preconditions.checkArgument(values == null || values.length == itemIDs.length,
            "Number of values doesn't match number of items");
    StringBuilder urlPath = new StringBuilder(32);
    urlPath.append("/estimateForAnonymous/");
    urlPath.append(toItemID);/*from w  w  w.ja  v  a2  s  .  co  m*/
    for (int i = 0; i < itemIDs.length; i++) {
        urlPath.append('/').append(itemIDs[i]);
        if (values != null) {
            urlPath.append('=').append(values[i]);
        }
    }

    // Requests are typically partitioned by user, but this request does not directly depend on a user.
    // If a user ID is supplied anyway, use it for partitioning since it will follow routing for other
    // requests related to that user. Otherwise just partition on the "to" item ID, which is at least
    // deterministic.
    long idToPartitionOn = contextUserID == null ? toItemID : contextUserID;

    TasteException savedException = null;
    for (HostAndPort replica : choosePartitionAndReplicas(idToPartitionOn)) {
        HttpURLConnection connection = null;
        try {
            connection = buildConnectionToReplica(replica, urlPath.toString(), "GET");
            switch (connection.getResponseCode()) {
            case HttpURLConnection.HTTP_OK:
                BufferedReader reader = IOUtils.bufferStream(connection.getInputStream());
                try {
                    return LangUtils.parseFloat(reader.readLine());
                } finally {
                    reader.close();
                }
            case HttpURLConnection.HTTP_NOT_FOUND:
                throw new NoSuchItemException(Arrays.toString(itemIDs) + ' ' + toItemID);
            case HttpURLConnection.HTTP_UNAVAILABLE:
                throw new NotReadyException();
            default:
                throw new TasteException(connection.getResponseCode() + " " + connection.getResponseMessage());
            }
        } catch (TasteException te) {
            log.info("Can't access {} at {}: ({})", urlPath, replica, te.toString());
            savedException = te;
        } catch (IOException ioe) {
            log.info("Can't access {} at {}: ({})", urlPath, replica, ioe.toString());
            savedException = new TasteException(ioe);
        } finally {
            if (connection != null) {
                connection.disconnect();
            }
        }
    }
    throw savedException;
}

From source file:org.eclipse.hono.client.impl.HonoClientImpl.java

Future<MessageConsumer> createConsumer(final String tenantId,
        final Supplier<Future<MessageConsumer>> newConsumerSupplier) {

    final Future<MessageConsumer> result = Future.future();
    context.runOnContext(get -> {/*from  ww  w.  jav  a2  s .c o m*/

        // register a handler to be notified if the underlying connection to the server fails
        // so that we can fail the result handler passed in
        final Handler<Void> connectionFailureHandler = connectionLost -> {
            result.tryFail(
                    new ServerErrorException(HttpURLConnection.HTTP_UNAVAILABLE, "connection to server lost"));
        };
        creationRequests.add(connectionFailureHandler);

        newConsumerSupplier.get().setHandler(attempt -> {
            creationRequests.remove(connectionFailureHandler);
            if (attempt.succeeded()) {
                result.tryComplete(attempt.result());
            } else {
                result.tryFail(attempt.cause());
            }
        });
    });
    return result;
}

Example usage for java.net HttpURLConnection HTTP_UNAVAILABLE

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