Example usage for com.google.common.collect Iterators transform

List of usage examples for com.google.common.collect Iterators transform

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Introduction

In this page you can find the example usage for com.google.common.collect Iterators transform.

Prototype

public static <F, T> Iterator<T> transform(final Iterator<F> fromIterator,
        final Function<? super F, ? extends T> function)

Source Link

Document

Returns an iterator that applies function to each element of fromIterator .

Usage

From source file:com.jwsphere.accumulo.shell.ScanCompressionCommand.java

protected void printRecords(final CommandLine cl, Shell shellState, final Scanner scanner, PrintFile outFile)
        throws IOException {

    Iterator<List<KeyValue>> batched = Scans.toBatchIterator(scanner.iterator(), scanner.getBatchSize());

    final TransportCompression defaultCompression = new DefaultTransportCompression();
    final TransportCompression deflateCompression = new DeflateTransportCompression();
    final TransportCompression relativeKeyCompression = new RelativeKeyTransportCompression();
    final TransportCompression deflatedRelativeKeyCompression = new DeflatedRelativeKeyTransportCompression();

    Iterator<String> stats = Iterators.transform(batched, new Function<List<KeyValue>, String>() {
        public String apply(List<KeyValue> batch) {
            StringBuilder sb = new StringBuilder();
            sb.append("============ ScanResult compression stats =============").append('\n');
            sb.append(defaultCompression.evaluate(batch).toString()).append('\n');
            sb.append(deflateCompression.evaluate(batch).toString()).append('\n');
            sb.append(relativeKeyCompression.evaluate(batch).toString()).append('\n');
            sb.append(deflatedRelativeKeyCompression.evaluate(batch));
            sb.append("=======================================================").append("\n\n");
            return sb.toString();
        }//  w  ww .  j a  va  2s  . c om
    });

    shellState.printLines(stats, true);
}

From source file:org.apache.beam.runners.spark.translation.TranslationUtils.java

/** {@link KV} to pair flatmap function. */
public static <K, V> PairFlatMapFunction<Iterator<KV<K, V>>, K, V> toPairFlatMapFunction() {
    return new PairFlatMapFunction<Iterator<KV<K, V>>, K, V>() {
        @Override/*from  www  .j  a va  2s. com*/
        public Iterable<Tuple2<K, V>> call(final Iterator<KV<K, V>> itr) {
            final Iterator<Tuple2<K, V>> outputItr = Iterators.transform(itr,
                    new com.google.common.base.Function<KV<K, V>, Tuple2<K, V>>() {

                        @Override
                        public Tuple2<K, V> apply(KV<K, V> kv) {
                            return new Tuple2<>(kv.getKey(), kv.getValue());
                        }
                    });
            return new Iterable<Tuple2<K, V>>() {

                @Override
                public Iterator<Tuple2<K, V>> iterator() {
                    return outputItr;
                }
            };
        }
    };
}

From source file:edu.harvard.med.screensaver.ui.arch.util.AttachedFiles.java

public DataModel getAttachedFilesDataModel() {
    if (_entity == null) {
        return new ListDataModel();
    }//from  ww w .  j  a  va 2  s.c  o  m
    List<AttachedFile> attachedFilesUnfiltered = Lists
            .newArrayList(Iterables.filter(_entity.getAttachedFiles(), _attachedFileFilter));
    List<AttachedFile> attachedFiles = Lists.newArrayList(
            Iterators.transform(attachedFilesUnfiltered.iterator(), new Function<AttachedFile, AttachedFile>() {

                @Override
                public AttachedFile apply(AttachedFile from) {
                    return (AttachedFile) from.restrict();
                }
            }));
    Collections.sort(attachedFiles);
    return new ListDataModel(attachedFiles);
}

From source file:qdg.view.MixedGraphAsDiGraph.java

@Override
public Iterator<Edge> getOutArcIterator(Node node) {
    Iterator<Edge> arcs = Iterators.transform(g.getOutArcIterator(node), forwardEdge);
    Iterator<Edge> uEdges = new OutArcIterator(node);
    return new ConcatIterator<Edge>(arcs, uEdges);
}

From source file:org.apache.rya.export.accumulo.AccumuloRyaStatementStore.java

@Override
public Iterator<RyaStatement> fetchStatements() throws FetchStatementException {
    try {/*from   w w w  . ja v a2 s .  c o  m*/
        final RyaTripleContext ryaTripleContext = RyaTripleContext.getInstance(accumuloRyaDao.getConf());

        Scanner scanner = null;
        try {
            scanner = AccumuloRyaUtils.getScanner(tablePrefix + RdfCloudTripleStoreConstants.TBL_SPO_SUFFIX,
                    accumuloRyaDao.getConf());
            for (final IteratorSetting iteratorSetting : iteratorSettings) {
                scanner.addScanIterator(iteratorSetting);
            }
        } catch (final IOException e) {
            throw new FetchStatementException("Unable to get scanner to fetch Rya Statements", e);
        }
        // Convert Entry iterator to RyaStatement iterator
        final Iterator<Entry<Key, Value>> entryIter = scanner.iterator();
        final Iterator<RyaStatement> ryaStatementIter = Iterators.transform(entryIter,
                new Function<Entry<Key, Value>, RyaStatement>() {
                    @Override
                    public RyaStatement apply(final Entry<Key, Value> entry) {
                        final Key key = entry.getKey();
                        final Value value = entry.getValue();
                        RyaStatement ryaStatement = null;
                        try {
                            ryaStatement = AccumuloRyaUtils.createRyaStatement(key, value, ryaTripleContext);
                        } catch (final TripleRowResolverException e) {
                            log.error("Unable to convert the key/value pair into a Rya Statement", e);
                        }
                        return ryaStatement;
                    }
                });
        return ryaStatementIter;
    } catch (final Exception e) {
        throw new FetchStatementException("Failed to fetch statements.", e);
    }
}

From source file:org.apache.mahout.math.hadoop.DistributedRowMatrix.java

@Override
public Iterator<MatrixSlice> iterateAll() {
    try {/*from  w ww.java2s  .  c  om*/
        Path pathPattern = rowPath;
        if (FileSystem.get(conf).getFileStatus(rowPath).isDir()) {
            pathPattern = new Path(rowPath, "*");
        }
        return Iterators.transform(
                new SequenceFileDirIterator<IntWritable, VectorWritable>(pathPattern, PathType.GLOB,
                        PathFilters.logsCRCFilter(), null, true, conf),
                new Function<Pair<IntWritable, VectorWritable>, MatrixSlice>() {
                    @Override
                    public MatrixSlice apply(Pair<IntWritable, VectorWritable> from) {
                        return new MatrixSlice(from.getSecond().get(), from.getFirst().get());
                    }
                });
    } catch (IOException ioe) {
        throw new IllegalStateException(ioe);
    }
}

From source file:com.google.gcloud.datastore.DatastoreServiceImpl.java

@Override
public List<Key> allocateId(IncompleteKey... keys) {
    if (keys.length == 0) {
        return Collections.emptyList();
    }//www. j  a v a 2s  .  c  o  m
    DatastoreV1.AllocateIdsRequest.Builder requestPb = DatastoreV1.AllocateIdsRequest.newBuilder();
    for (IncompleteKey key : keys) {
        requestPb.addKey(trimNameOrId(key).toPb());
    }
    DatastoreV1.AllocateIdsResponse responsePb = allocateIds(requestPb.build());
    Iterator<DatastoreV1.Key> keyIterator = responsePb.getKeyList().iterator();
    ImmutableList.Builder<Key> builder = ImmutableList.<Key>builder()
            .addAll(Iterators.transform(keyIterator, new Function<DatastoreV1.Key, Key>() {
                @Override
                public Key apply(DatastoreV1.Key keyPb) {
                    return Key.fromPb(keyPb);
                }
            }));
    return builder.build();
}

From source file:org.geogit.api.plumbing.DeepMove.java

private void moveObjects(final ObjectDatabase from, final ObjectDatabase to,
        Supplier<Iterator<Node>> nodesToMove, final Set<ObjectId> metadataIds) {

    Function<Node, ObjectId> asIds = new Function<Node, ObjectId>() {
        @Override/*from www .  j av a  2  s  .co m*/
        public ObjectId apply(Node input) {
            return input.getObjectId();
        }
    };
    Function<Node, RevObject> asObjects = new Function<Node, RevObject>() {
        @Override
        public RevObject apply(Node input) {
            if (input.getMetadataId().isPresent()) {
                metadataIds.add(input.getMetadataId().get());
            }
            return from.get(input.getObjectId());
        }
    };

    Iterator<Node> iterator;
    iterator = nodesToMove.get();
    if (iterator.hasNext()) {
        to.putAll(Iterators.transform(iterator, asObjects));

        iterator = nodesToMove.get();
        from.deleteAll(Iterators.transform(iterator, asIds));
    }
}

From source file:org.kitesdk.data.spi.filesystem.FileSystemPartitionIterator.java

@SuppressWarnings("deprecation")
FileSystemPartitionIterator(FileSystem fs, Path root, PartitionStrategy strategy, final Constraints constraints)
        throws IOException {
    Preconditions.checkArgument(fs.isDirectory(root));
    this.fs = fs;
    this.rootDirectory = root;
    this.iterator = Iterators.filter(Iterators
            .transform(new FileSystemIterator(strategy.getFieldPartitioners().size()), new MakeKey(strategy)),
            new KeyPredicate(constraints.toKeyPredicate()));
}

From source file:org.apache.gobblin.runtime.local.LocalJobLauncher.java

@Override
protected void runWorkUnitStream(WorkUnitStream workUnitStream) throws Exception {
    String jobId = this.jobContext.getJobId();
    final JobState jobState = this.jobContext.getJobState();

    Iterator<WorkUnit> workUnitIterator = workUnitStream.getWorkUnits();
    if (!workUnitIterator.hasNext()) {
        LOG.warn("No work units to run");
        return;/*from w  w  w . j  av a  2  s. c  o m*/
    }

    TimingEvent workUnitsRunTimer = this.eventSubmitter
            .getTimingEvent(TimingEvent.RunJobTimings.WORK_UNITS_RUN);
    Iterator<WorkUnit> flattenedWorkUnits = new MultiWorkUnitUnpackingIterator(workUnitStream.getWorkUnits());
    Iterator<WorkUnit> workUnitsWithJobState = Iterators.transform(flattenedWorkUnits,
            new Function<WorkUnit, WorkUnit>() {
                @Override
                public WorkUnit apply(WorkUnit workUnit) {
                    workUnit.addAllIfNotExist(jobState);
                    return workUnit;
                }
            });

    GobblinMultiTaskAttempt.runWorkUnits(this.jobContext, workUnitsWithJobState, this.taskStateTracker,
            this.taskExecutor, GobblinMultiTaskAttempt.CommitPolicy.IMMEDIATE);

    if (this.cancellationRequested) {
        // Wait for the cancellation execution if it has been requested
        synchronized (this.cancellationExecution) {
            if (this.cancellationExecuted) {
                return;
            }
        }
    }
    workUnitsRunTimer.stop();

    LOG.info(String.format("All tasks of job %s have completed", jobId));

    if (jobState.getState() == JobState.RunningState.RUNNING) {
        jobState.setState(JobState.RunningState.SUCCESSFUL);
    }
}