Example usage for java.util LinkedList isEmpty

List of usage examples for java.util LinkedList isEmpty

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Introduction

In this page you can find the example usage for java.util LinkedList isEmpty.

Prototype

boolean isEmpty();

Source Link

Document

Returns true if this list contains no elements.

Usage

From source file:com.icantrap.collections.dawg.DawgBuilder.java

/**
 * Builds the dawg based on the words added.
 *
 * @return the new Dawg instance/*from w ww . ja v a 2s  .  c  om*/
 */
public Dawg build() {
    compress();

    for (Node node : nodeList)
        node.index = -1;

    LinkedList<Node> stack = new LinkedList<Node>();

    nodeList.clear();
    stack.clear();
    stack.addLast(root);

    int index = 0;

    while (!stack.isEmpty()) {
        Node ptr = stack.removeFirst();
        if (-1 == ptr.index)
            ptr.index = index++;
        nodeList.add(ptr);

        for (Node nextChild : ptr.nextChildren)
            stack.addLast(nextChild);
        if (null != ptr.child)
            stack.addLast(ptr.child);
    }

    int[] ints = new int[index];

    for (Node node : nodeList)
        ints[node.index] = node.toInteger();

    return new Dawg(ints);
}

From source file:com.zjy.mongo.splitter.ShardChunkMongoSplitter.java

@Override
public List<InputSplit> calculateSplits() throws SplitFailedException {
    boolean targetShards = MongoConfigUtil.canReadSplitsFromShards(getConfiguration());
    DB configDB = getConfigDB();/*from  www .  jav a 2  s . c  o m*/
    DBCollection chunksCollection = configDB.getCollection("chunks");

    MongoClientURI inputURI = MongoConfigUtil.getInputURI(getConfiguration());
    String inputNS = inputURI.getDatabase() + "." + inputURI.getCollection();

    DBCursor cur = chunksCollection.find(new BasicDBObject("ns", inputNS));

    int numChunks = 0;

    Map<String, String> shardsMap = null;
    if (targetShards) {
        try {
            shardsMap = getShardsMap();
        } catch (Exception e) {
            //Something went wrong when trying to
            //read the shards data from the config server,
            //so abort the splitting
            throw new SplitFailedException("Couldn't get shards information from config server", e);
        }
    }

    List<String> mongosHostNames = MongoConfigUtil.getInputMongosHosts(getConfiguration());
    if (targetShards && mongosHostNames.size() > 0) {
        throw new SplitFailedException(
                "Setting both mongo.input.split.read_from_shards and mongo.input.mongos_hosts"
                        + " does not make sense. ");
    }

    if (mongosHostNames.size() > 0) {
        LOG.info("Using multiple mongos instances (round robin) for reading input.");
    }

    Map<String, LinkedList<InputSplit>> shardToSplits = new HashMap<String, LinkedList<InputSplit>>();

    try {
        while (cur.hasNext()) {
            final BasicDBObject row = (BasicDBObject) cur.next();
            BasicDBObject chunkLowerBound = (BasicDBObject) row.get("min");
            BasicDBObject chunkUpperBound = (BasicDBObject) row.get("max");
            MongoInputSplit chunkSplit = createSplitFromBounds(chunkLowerBound, chunkUpperBound);
            chunkSplit.setInputURI(inputURI);
            String shard = (String) row.get("shard");
            if (targetShards) {
                //The job is configured to target shards, so replace the
                //mongos hostname with the host of the shard's servers
                String shardHosts = shardsMap.get(shard);
                if (shardHosts == null) {
                    throw new SplitFailedException("Couldn't find shard ID: " + shard + " in config.shards.");
                }

                MongoClientURI newURI = rewriteURI(inputURI, shardHosts);
                chunkSplit.setInputURI(newURI);
            } else if (mongosHostNames.size() > 0) {
                //Multiple mongos hosts are specified, so
                //choose a host name in round-robin fashion
                //and rewrite the URI using that hostname.
                //This evenly distributes the load to avoid
                //pegging a single mongos instance.
                String roundRobinHost = mongosHostNames.get(numChunks % mongosHostNames.size());
                MongoClientURI newURI = rewriteURI(inputURI, roundRobinHost);
                chunkSplit.setInputURI(newURI);
            }
            LinkedList<InputSplit> shardList = shardToSplits.get(shard);
            if (shardList == null) {
                shardList = new LinkedList<InputSplit>();
                shardToSplits.put(shard, shardList);
            }
            chunkSplit.setKeyField(MongoConfigUtil.getInputKey(getConfiguration()));
            shardList.add(chunkSplit);
            numChunks++;
        }
    } finally {
        MongoConfigUtil.close(configDB.getMongo());
    }

    final List<InputSplit> splits = new ArrayList<InputSplit>(numChunks);
    int splitIndex = 0;
    while (splitIndex < numChunks) {
        Set<String> shardSplitsToRemove = new HashSet<String>();
        for (Entry<String, LinkedList<InputSplit>> shardSplits : shardToSplits.entrySet()) {
            LinkedList<InputSplit> shardSplitsList = shardSplits.getValue();
            InputSplit split = shardSplitsList.pop();
            splits.add(splitIndex, split);
            splitIndex++;
            if (shardSplitsList.isEmpty()) {
                shardSplitsToRemove.add(shardSplits.getKey());
            }
        }
        for (String shardName : shardSplitsToRemove) {
            shardToSplits.remove(shardName);
        }
    }

    return splits;
}

From source file:com.kixeye.chassis.support.metrics.aws.MetricsCloudWatchReporter.java

@Override
@SuppressWarnings("rawtypes")
public void report(SortedMap<String, Gauge> gauges, SortedMap<String, Counter> counters,
        SortedMap<String, Histogram> histograms, SortedMap<String, Meter> meters,
        SortedMap<String, Timer> timers) {

    logger.info("Starting metrics publishing to AWS CloudWatch.");

    LinkedList<PutMetricDataRequest> requests = new LinkedList<>();

    addMetricData(gauges, counters, histograms, meters, timers, requests, new Date());

    if (requests.isEmpty()) {
        logger.debug("No metric data to send to AWS.");
        return;/*from  www. ja  va2 s .  c  om*/
    }

    for (PutMetricDataRequest request : requests) {
        try {
            for (MetricDatum datum : request.getMetricData()) {
                logger.debug("Sending metric " + datum);
            }
            cloudWatch.putMetricData(request);
        } catch (Exception e) {
            logger.error("Failed to log metrics to CloudWatch discarding metrics for this attempt...", e);
            return;
        }
    }
    logger.info("Finished metrics publishing to AWS CloudWatch.");
}

From source file:com.splicemachine.derby.stream.function.merge.AbstractMergeJoinFlatMapFunction.java

protected void initRightScan(PeekingIterator<LocatedRow> leftPeekingIterator) throws StandardException {
    ExecRow firstHashRow = joinOperation.getKeyRow(leftPeekingIterator.peek().getRow());
    ExecRow startPosition = joinOperation.getRightResultSet().getStartPosition();
    int[] columnOrdering = getColumnOrdering(joinOperation.getRightResultSet());
    int nCols = startPosition != null ? startPosition.nColumns() : 0;
    ExecRow scanStartOverride = null;/*w  ww  .java  2s . co m*/
    int[] scanKeys = null;
    // If start row of right table scan has as many columns as key colummns of the table, cannot further
    // narrow down scan space, so return right tabel scan start row.
    if (nCols == columnOrdering.length) {
        scanStartOverride = startPosition;
        scanKeys = columnOrdering;
    } else {
        int[] rightHashKeys = joinOperation.getRightHashKeys();
        // Find valid hash column values to narrow down right scan. The valid hash columns must:
        // 1) not be used as a start key for inner table scan
        // 2) be consecutive
        // 3) be a key column
        LinkedList<Pair<Integer, Integer>> hashColumnIndexList = new LinkedList<>();
        for (int i = 0; i < rightHashKeys.length; ++i) {
            if (rightHashKeys[i] > nCols - 1) {
                if ((hashColumnIndexList.isEmpty()
                        || hashColumnIndexList.getLast().getValue() == rightHashKeys[i] - 1)
                        && isKeyColumn(columnOrdering, rightHashKeys[i])) {
                    hashColumnIndexList.add(new ImmutablePair<Integer, Integer>(i, rightHashKeys[i]));
                } else {
                    break;
                }
            }
        }

        scanStartOverride = new ValueRow(nCols + hashColumnIndexList.size());
        if (startPosition != null) {
            for (int i = 1; i <= startPosition.nColumns(); ++i) {
                scanStartOverride.setColumn(i, startPosition.getColumn(i));
            }
        }
        for (int i = 0; i < hashColumnIndexList.size(); ++i) {
            Pair<Integer, Integer> hashColumnIndex = hashColumnIndexList.get(i);
            int index = hashColumnIndex.getKey();
            scanStartOverride.setColumn(nCols + i + 1, firstHashRow.getColumn(index + 1));
        }

        // Scan key should include columns
        // 1) preceding the first hash column, these columns are in the form of "col=constant"
        // 2) all hash columns that are key columns
        scanKeys = new int[hashColumnIndexList.size() + rightHashKeys[0]];
        for (int i = 0; i < rightHashKeys[0]; ++i) {
            scanKeys[i] = i;
        }
        for (int i = 0; i < hashColumnIndexList.size(); ++i) {
            Pair<Integer, Integer> hashColumnIndex = hashColumnIndexList.get(i);
            int colPos = hashColumnIndex.getValue();
            scanKeys[rightHashKeys[0] + i] = colPos;
        }
    }

    ((BaseActivation) joinOperation.getActivation()).setScanStartOverride(scanStartOverride);
    ((BaseActivation) joinOperation.getActivation()).setScanKeys(scanKeys);
    if (startPosition != null) {
        ((BaseActivation) joinOperation.getActivation()).setScanStopOverride(startPosition);
    }

}

From source file:com.asakusafw.runtime.stage.launcher.LauncherOptionsParser.java

private String consumeApplicationClassName(LinkedList<String> rest) {
    if (rest.isEmpty()) {
        throw new IllegalArgumentException("the first argument must be target application class name");
    }/*from   ww  w  .j a  v a  2s.c  o  m*/
    return rest.removeFirst();
}

From source file:com.github.lindenb.jvarkit.tools.misc.BamTile.java

@Override
public Collection<Throwable> call(final String inputName) throws Exception {
    SAMRecordIterator iter = null;//from   w  ww  .  j  a  va  2  s.  c  om
    SamReader sfr = null;
    SAMFileWriter sfw = null;
    try {
        sfr = openSamReader(inputName);

        SAMFileHeader header1 = sfr.getFileHeader();
        if (header1 == null) {
            return wrapException("File header missing");
        }

        if (header1.getSortOrder() != SAMFileHeader.SortOrder.coordinate) {
            return wrapException("File header not sorted on coordinate");
        }

        SAMFileHeader header2 = header1.clone();
        header2.addComment(getName() + ":" + getVersion() + ":" + getProgramCommandLine());

        sfw = openSAMFileWriter(header2, true);

        SAMSequenceDictionaryProgress progress = new SAMSequenceDictionaryProgress(header1);
        iter = sfr.iterator();
        LinkedList<SAMRecord> buffer = new LinkedList<>();
        for (;;) {
            SAMRecord rec = null;
            if (iter.hasNext()) {
                rec = progress.watch(iter.next());
                if (rec.getReadUnmappedFlag())
                    continue;
                if (!buffer.isEmpty()) {
                    SAMRecord last = buffer.getLast();
                    if (last.getReferenceIndex() == rec.getReferenceIndex()
                            && last.getAlignmentStart() <= rec.getAlignmentStart()
                            && last.getAlignmentEnd() >= rec.getAlignmentEnd()) {
                        continue;
                    }
                }
            }
            if (rec == null
                    || (!buffer.isEmpty() && buffer.getLast().getReferenceIndex() != rec.getReferenceIndex())) {
                while (!buffer.isEmpty()) {
                    sfw.addAlignment(buffer.removeFirst());
                }
                if (rec == null)
                    break;
            }
            buffer.add(rec);

            if (buffer.size() > 2) {
                int index = buffer.size();
                SAMRecord prev = buffer.get(index - 3);
                SAMRecord curr = buffer.get(index - 2);
                SAMRecord next = buffer.get(index - 1);

                if (prev.getAlignmentEnd() >= next.getAlignmentStart()
                        || curr.getAlignmentEnd() <= prev.getAlignmentEnd()) {
                    buffer.remove(index - 2);
                } else if (curr.getAlignmentStart() == prev.getAlignmentStart()
                        && curr.getAlignmentEnd() > prev.getAlignmentEnd()) {
                    buffer.remove(index - 3);
                }

            }
            while (buffer.size() > 3) {
                sfw.addAlignment(buffer.removeFirst());
            }

        }
        progress.finish();
        LOG.info("done");
        return Collections.emptyList();
    } catch (Exception err) {
        return wrapException(err);
    } finally {
        CloserUtil.close(iter);
        CloserUtil.close(sfr);
        CloserUtil.close(sfw);
    }
}

From source file:org.springframework.cloud.contract.verifier.util.DelegatingJsonVerifiable.java

private String createMethodString() {
    LinkedList<String> queue = new LinkedList<>(this.methodsBuffer);
    StringBuilder stringBuffer = new StringBuilder();
    while (!queue.isEmpty()) {
        stringBuffer.append(queue.remove());
    }/*from   ww  w .j ava 2s.  c o m*/
    return stringBuffer.toString();
}

From source file:org.codice.ddf.security.filter.delegate.DelegateServletFilter.java

@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
        throws IOException, ServletException {

    HttpServletRequest httpRequest = (HttpServletRequest) servletRequest;

    if (contextPolicyManager != null) {
        String contextPath = !StringUtils.isBlank(httpRequest.getContextPath()) ? httpRequest.getContextPath()
                : httpRequest.getServletPath() + httpRequest.getPathInfo();
        if (contextPolicyManager.isWhiteListed(contextPath)) {
            LOGGER.debug(//from ww  w.  j  av a  2 s .  co m
                    "Current Context path {} has been white listed by the local policy, no authentication or authorization filters will be applied.",
                    contextPath);
            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }
    }

    LinkedList<ServiceReference<Filter>> serviceRefs = new LinkedList<ServiceReference<Filter>>();
    try {
        serviceRefs.addAll(ctx.getServiceReferences(Filter.class, null));
    } catch (InvalidSyntaxException e) {
        LOGGER.warn("Could not lookup service references.", e);
    }

    if (!serviceRefs.isEmpty()) {
        LOGGER.debug("Found {} filter, now filtering...", serviceRefs.size());

        ProxyFilterChain chain = new ProxyFilterChain(filterChain);

        Iterator<ServiceReference<Filter>> reverseIterator = serviceRefs.descendingIterator();
        while (reverseIterator.hasNext()) {
            ServiceReference<Filter> curReference = reverseIterator.next();
            Filter curFilter = ctx.getService(curReference);
            if (!curFilter.getClass().toString().equals(this.getClass().toString())) {
                chain.addFilter(curFilter);
            }
            reverseIterator.remove();
        }

        chain.doFilter(servletRequest, servletResponse);
    } else {
        LOGGER.debug("Did not find any filters");
        filterChain.doFilter(servletRequest, servletResponse);
    }
}

From source file:ca.uhn.fhir.context.RuntimeResourceDefinition.java

private void fillBasics(StructureElement theElement, BaseRuntimeElementDefinition<?> def,
        LinkedList<String> path, BaseRuntimeDeclaredChildDefinition theChild) {
    if (path.isEmpty()) {
        path.add(def.getName());/* ww  w. j  a v a  2 s. c  om*/
        theElement.setName(def.getName());
    } else {
        path.add(WordUtils.uncapitalize(theChild.getElementName()));
        theElement.setName(theChild.getElementName());
    }
    theElement.setPath(StringUtils.join(path, '.'));
}

From source file:mitm.djigzo.web.services.security.HMACFilterImpl.java

private void calculateHMACs(MarkupWriter writer, List<String> hmacs) {
    Document document = writer.getDocument();

    if (document != null) {
        Element root = document.getRootElement();

        if (root != null) {
            LinkedList<Element> queue = new LinkedList<Element>();

            queue.add(root);/*from w  ww.jav a 2  s .  c om*/

            while (!queue.isEmpty()) {
                Element element = queue.removeFirst();

                if (element == null) {
                    continue;
                }

                String elementName = element.getAttribute("name");

                if (elementName != null) {
                    elementName = elementName.trim().toLowerCase();
                }

                if (protectedElements.contains(elementName)) {
                    /*
                     * It's a protected item so we should calculate the HMAC of the value
                     */
                    String value = element.getAttribute("value");

                    String hmac;

                    try {
                        hmac = calculateHMAC(value, true /* create ASO if not exist */);
                    } catch (InvalidKeyException e) {
                        throw new DjigzoRuntimeException(e);
                    } catch (NoSuchAlgorithmException e) {
                        throw new DjigzoRuntimeException(e);
                    }

                    if (hmac == null) {
                        throw new DjigzoRuntimeException("hmac is null.");
                    }

                    if (hmacs != null) {
                        hmacs.add(hmac);
                    } else {
                        /*
                         * Add the HMAC checksum as a hidden element
                         */
                        element.element("input", "type", "hidden", "name", HMAC_PARAMETER, "value", hmac);
                    }
                }

                for (Node n : element.getChildren()) {
                    Element child = null;

                    if (n instanceof Element) {
                        child = (Element) n;
                    }

                    if (child != null)
                        queue.addLast(child);
                }
            }
        }
    }
}