Java Code Examples for java.util.Collections#emptyIterator()
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java.util.Collections#emptyIterator() .
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Example 1
Source Project: Bytecoder File: ImageIO.java License: Apache License 2.0 | 6 votes |
/** * Returns an {@code Iterator} containing all currently * registered {@code ImageTranscoder}s that claim to be * able to transcode between the metadata of the given * {@code ImageReader} and {@code ImageWriter}. * * @param reader an {@code ImageReader}. * @param writer an {@code ImageWriter}. * * @return an {@code Iterator} containing * {@code ImageTranscoder}s. * * @exception IllegalArgumentException if {@code reader} or * {@code writer} is {@code null}. */ public static Iterator<ImageTranscoder> getImageTranscoders(ImageReader reader, ImageWriter writer) { if (reader == null) { throw new IllegalArgumentException("reader == null!"); } if (writer == null) { throw new IllegalArgumentException("writer == null!"); } ImageReaderSpi readerSpi = reader.getOriginatingProvider(); ImageWriterSpi writerSpi = writer.getOriginatingProvider(); ServiceRegistry.Filter filter = new TranscoderFilter(readerSpi, writerSpi); Iterator<ImageTranscoderSpi> iter; // Ensure category is present try { iter = theRegistry.getServiceProviders(ImageTranscoderSpi.class, filter, true); } catch (IllegalArgumentException e) { return Collections.emptyIterator(); } return new ImageTranscoderIterator(iter); }
Example 2
Source Project: openjdk-8-source File: ImageIO.java License: GNU General Public License v2.0 | 6 votes |
/** * Returns an <code>Iterator</code> containing all currently * registered <code>ImageWriter</code>s that claim to be able to * encode the named format. * * @param formatName a <code>String</code> containing the informal * name of a format (<i>e.g.</i>, "jpeg" or "tiff". * * @return an <code>Iterator</code> containing * <code>ImageWriter</code>s. * * @exception IllegalArgumentException if <code>formatName</code> is * <code>null</code>. * * @see javax.imageio.spi.ImageWriterSpi#getFormatNames */ public static Iterator<ImageWriter> getImageWritersByFormatName(String formatName) { if (formatName == null) { throw new IllegalArgumentException("formatName == null!"); } Iterator iter; // Ensure category is present try { iter = theRegistry.getServiceProviders(ImageWriterSpi.class, new ContainsFilter(writerFormatNamesMethod, formatName), true); } catch (IllegalArgumentException e) { return Collections.emptyIterator(); } return new ImageWriterIterator(iter); }
Example 3
Source Project: JDKSourceCode1.8 File: ImageIO.java License: MIT License | 6 votes |
/** * Returns an <code>Iterator</code> containing all currently * registered <code>ImageWriter</code>s that claim to be able to * encode the named format. * * @param formatName a <code>String</code> containing the informal * name of a format (<i>e.g.</i>, "jpeg" or "tiff". * * @return an <code>Iterator</code> containing * <code>ImageWriter</code>s. * * @exception IllegalArgumentException if <code>formatName</code> is * <code>null</code>. * * @see javax.imageio.spi.ImageWriterSpi#getFormatNames */ public static Iterator<ImageWriter> getImageWritersByFormatName(String formatName) { if (formatName == null) { throw new IllegalArgumentException("formatName == null!"); } Iterator iter; // Ensure category is present try { iter = theRegistry.getServiceProviders(ImageWriterSpi.class, new ContainsFilter(writerFormatNamesMethod, formatName), true); } catch (IllegalArgumentException e) { return Collections.emptyIterator(); } return new ImageWriterIterator(iter); }
Example 4
Source Project: openjdk-jdk9 File: ScriptRuntime.java License: GNU General Public License v2.0 | 6 votes |
/** * Returns an iterator over property values used in the {@code for each...in} statement. Aside from built-in JS * objects, it also operates on Java arrays, any {@link Iterable}, as well as on {@link Map} objects, iterating over * map values. * @param obj object to iterate on. * @return iterator over the object's property values. */ public static Iterator<?> toValueIterator(final Object obj) { if (obj instanceof ScriptObject) { return ((ScriptObject)obj).valueIterator(); } if (obj instanceof JSObject) { return ((JSObject)obj).values().iterator(); } final Iterator<?> itr = iteratorForJavaArrayOrList(obj); if (itr != null) { return itr; } if (obj instanceof Map) { return ((Map<?,?>)obj).values().iterator(); } final Object wrapped = Global.instance().wrapAsObject(obj); if (wrapped instanceof ScriptObject) { return ((ScriptObject)wrapped).valueIterator(); } return Collections.emptyIterator(); }
Example 5
Source Project: hottub File: ImageIO.java License: GNU General Public License v2.0 | 6 votes |
/** * Returns an <code>Iterator</code> containing all currently * registered <code>ImageWriter</code>s that claim to be able to * encode files with the given suffix. * * @param fileSuffix a <code>String</code> containing a file * suffix (<i>e.g.</i>, "jpg" or "tiff"). * * @return an <code>Iterator</code> containing <code>ImageWriter</code>s. * * @exception IllegalArgumentException if <code>fileSuffix</code> is * <code>null</code>. * * @see javax.imageio.spi.ImageWriterSpi#getFileSuffixes */ public static Iterator<ImageWriter> getImageWritersBySuffix(String fileSuffix) { if (fileSuffix == null) { throw new IllegalArgumentException("fileSuffix == null!"); } Iterator iter; // Ensure category is present try { iter = theRegistry.getServiceProviders(ImageWriterSpi.class, new ContainsFilter(writerFileSuffixesMethod, fileSuffix), true); } catch (IllegalArgumentException e) { return Collections.emptyIterator(); } return new ImageWriterIterator(iter); }
Example 6
Source Project: grakn File: JanusGraphPropertiesStep.java License: GNU Affero General Public License v3.0 | 6 votes |
@Override protected Iterator<E> flatMap(Traverser.Admin<Element> traverser) { if (useMultiQuery) { //it is guaranteed that all elements are vertices if (multiQueryResults == null || !multiQueryResults.containsKey(traverser.get())) { initializeMultiQuery(Arrays.asList(traverser)); } return convertIterator(multiQueryResults.get(traverser.get())); } else if (traverser.get() instanceof JanusGraphVertex || traverser.get() instanceof WrappedVertex) { JanusGraphVertexQuery query = makeQuery((JanusGraphTraversalUtil.getJanusGraphVertex(traverser)).query()); return convertIterator(query.properties()); } else { //It is some other element (edge or vertex property) Iterator<E> iterator; if (getReturnType().forValues()) { iterator = traverser.get().values(getPropertyKeys()); } else { //HasContainers don't apply => empty result set if (!hasContainers.isEmpty()) return Collections.emptyIterator(); iterator = (Iterator<E>) traverser.get().properties(getPropertyKeys()); } if (limit != Query.NO_LIMIT) iterator = Iterators.limit(iterator, limit); return iterator; } }
Example 7
Source Project: jdk1.8-source-analysis File: ImageIO.java License: Apache License 2.0 | 6 votes |
/** * Returns an <code>Iterator</code> containing all currently * registered <code>ImageWriter</code>s that claim to be able to * encode the named format. * * @param formatName a <code>String</code> containing the informal * name of a format (<i>e.g.</i>, "jpeg" or "tiff". * * @return an <code>Iterator</code> containing * <code>ImageWriter</code>s. * * @exception IllegalArgumentException if <code>formatName</code> is * <code>null</code>. * * @see javax.imageio.spi.ImageWriterSpi#getFormatNames */ public static Iterator<ImageWriter> getImageWritersByFormatName(String formatName) { if (formatName == null) { throw new IllegalArgumentException("formatName == null!"); } Iterator iter; // Ensure category is present try { iter = theRegistry.getServiceProviders(ImageWriterSpi.class, new ContainsFilter(writerFormatNamesMethod, formatName), true); } catch (IllegalArgumentException e) { return Collections.emptyIterator(); } return new ImageWriterIterator(iter); }
Example 8
Source Project: openjdk-jdk8u File: ImageIO.java License: GNU General Public License v2.0 | 6 votes |
/** * Returns an <code>Iterator</code> containing all currently * registered <code>ImageTranscoder</code>s that claim to be * able to transcode between the metadata of the given * <code>ImageReader</code> and <code>ImageWriter</code>. * * @param reader an <code>ImageReader</code>. * @param writer an <code>ImageWriter</code>. * * @return an <code>Iterator</code> containing * <code>ImageTranscoder</code>s. * * @exception IllegalArgumentException if <code>reader</code> or * <code>writer</code> is <code>null</code>. */ public static Iterator<ImageTranscoder> getImageTranscoders(ImageReader reader, ImageWriter writer) { if (reader == null) { throw new IllegalArgumentException("reader == null!"); } if (writer == null) { throw new IllegalArgumentException("writer == null!"); } ImageReaderSpi readerSpi = reader.getOriginatingProvider(); ImageWriterSpi writerSpi = writer.getOriginatingProvider(); ServiceRegistry.Filter filter = new TranscoderFilter(readerSpi, writerSpi); Iterator iter; // Ensure category is present try { iter = theRegistry.getServiceProviders(ImageTranscoderSpi.class, filter, true); } catch (IllegalArgumentException e) { return Collections.emptyIterator(); } return new ImageTranscoderIterator(iter); }
Example 9
Source Project: deeplearning4j File: SharedFlatMapMultiDataSet.java License: Apache License 2.0 | 6 votes |
@Override public Iterator<R> call(Iterator<MultiDataSet> dataSetIterator) throws Exception { //Under some limited circumstances, we might have an empty partition. In this case, we should return immediately if(!dataSetIterator.hasNext()){ return Collections.emptyIterator(); } /* That's the place where we do our stuff. Here's the plan: 1) we pass given iterator to VirtualDataSetIterator, which acts as holder for them 2) Virtual iterator will provide load balancing between available devices 3) we'll lock out here */ // iterator should be silently attached to VirtualDataSetIterator, and used appropriately SharedTrainingWrapper.getInstance(worker.getInstanceId()).attachMDS(dataSetIterator); // first callee will become master, others will obey and die // all threads in this executor will be blocked here until training finished SharedTrainingResult result = SharedTrainingWrapper.getInstance(worker.getInstanceId()).run(worker); return Collections.singletonList((R) result).iterator(); }
Example 10
Source Project: spliceengine File: ValueRowMappedJoinTable.java License: GNU Affero General Public License v3.0 | 5 votes |
@Override public Iterator<ExecRow> fetchInner(ExecRow outer) throws IOException, StandardException{ for (int i = 0; i < numKeys; i++) { keyRow.setColumn(i+1, outer.getColumn(outerHashKeys[i] + 1)); } List<ExecRow> rows = table.get(keyRow); if(rows==null) return Collections.emptyIterator(); else return rows.iterator(); }
Example 11
Source Project: quarkus File: SelectionResult.java License: Apache License 2.0 | 5 votes |
@Override public Iterator<Extension> iterator() { if (matches) { return extensions.iterator(); } return Collections.emptyIterator(); }
Example 12
Source Project: Bats File: LocalPersistentStore.java License: Apache License 2.0 | 5 votes |
@Override public Iterator<Map.Entry<String, V>> getRange(int skip, int take) { try { // list only files with sys file suffix PathFilter sysFileSuffixFilter = new PathFilter() { @Override public boolean accept(Path path) { return path.getName().endsWith(DRILL_SYS_FILE_SUFFIX); } }; List<FileStatus> fileStatuses = DrillFileSystemUtil.listFiles(fs, basePath, false, sysFileSuffixFilter); if (fileStatuses.isEmpty()) { return Collections.emptyIterator(); } List<String> files = Lists.newArrayList(); for (FileStatus stat : fileStatuses) { String s = stat.getPath().getName(); files.add(s.substring(0, s.length() - DRILL_SYS_FILE_SUFFIX.length())); } Collections.sort(files); return Iterables.transform(Iterables.limit(Iterables.skip(files, skip), take), new Function<String, Entry<String, V>>() { @Nullable @Override public Entry<String, V> apply(String key) { return new ImmutableEntry<>(key, get(key)); } }).iterator(); } catch (IOException e) { throw new RuntimeException(e); } }
Example 13
Source Project: dremio-oss File: ScanWithDremioReader.java License: Apache License 2.0 | 5 votes |
static Iterator<RecordReader> createReaders( final HiveConf hiveConf, final BaseHiveStoragePlugin hiveStoragePlugin, final FragmentExecutionContext fragmentExecContext, final OperatorContext context, final HiveProxyingSubScan config, final HiveTableXattr tableXattr, final CompositeReaderConfig compositeReader, final UserGroupInformation readerUGI, List<SplitAndPartitionInfo> splits) { try (ContextClassLoaderSwapper ccls = ContextClassLoaderSwapper.newInstance()) { if(splits.isEmpty()) { return Collections.emptyIterator(); } final JobConf jobConf = new JobConf(hiveConf); final List<HiveParquetSplit> sortedSplits = Lists.newArrayList(); for (SplitAndPartitionInfo split : splits) { sortedSplits.add(new HiveParquetSplit(split)); } Collections.sort(sortedSplits); return new HiveParquetSplitReaderIterator( jobConf, context, config, sortedSplits, readerUGI, compositeReader, hiveStoragePlugin, tableXattr); } catch (final Exception e) { throw Throwables.propagate(e); } }
Example 14
Source Project: iceberg File: CloseableIterable.java License: Apache License 2.0 | 5 votes |
static <E> CloseableIterable<E> empty() { return new CloseableIterable<E>() { @Override public void close() { } @Override public Iterator<E> iterator() { return Collections.emptyIterator(); } }; }
Example 15
Source Project: flink File: TaskSlotTableImpl.java License: Apache License 2.0 | 5 votes |
private TaskSlotIterator(JobID jobId, TaskSlotState state) { Set<AllocationID> allocationIds = slotsPerJob.get(jobId); if (allocationIds == null || allocationIds.isEmpty()) { allSlots = Collections.emptyIterator(); } else { allSlots = allocationIds.iterator(); } this.state = Preconditions.checkNotNull(state); this.currentSlot = null; }
Example 16
Source Project: spliceengine File: HResult.java License: GNU Affero General Public License v3.0 | 4 votes |
@Override public Iterator<DataCell> iterator(){ if(result==null||result.isEmpty()) return Collections.emptyIterator(); return Iterators.transform(result.listCells().iterator(),transform); }
Example 17
Source Project: TencentKona-8 File: ScriptRuntime.java License: GNU General Public License v2.0 | 4 votes |
/** * Returns an iterator over property values used in the {@code for each...in} statement. Aside from built-in JS * objects, it also operates on Java arrays, any {@link Iterable}, as well as on {@link Map} objects, iterating over * map values. * @param obj object to iterate on. * @return iterator over the object's property values. */ public static Iterator<?> toValueIterator(final Object obj) { if (obj instanceof ScriptObject) { return ((ScriptObject)obj).valueIterator(); } if (obj != null && obj.getClass().isArray()) { final Object array = obj; final int length = Array.getLength(obj); return new Iterator<Object>() { private int index = 0; @Override public boolean hasNext() { return index < length; } @Override public Object next() { if (index >= length) { throw new NoSuchElementException(); } return Array.get(array, index++); } @Override public void remove() { throw new UnsupportedOperationException("remove"); } }; } if (obj instanceof JSObject) { return ((JSObject)obj).values().iterator(); } if (obj instanceof Map) { return ((Map<?,?>)obj).values().iterator(); } if (obj instanceof Iterable) { return ((Iterable<?>)obj).iterator(); } final Object wrapped = Global.instance().wrapAsObject(obj); if (wrapped instanceof ScriptObject) { return ((ScriptObject)wrapped).valueIterator(); } return Collections.emptyIterator(); }
Example 18
Source Project: tinkerpop File: EmptyGraph.java License: Apache License 2.0 | 4 votes |
@Override public Iterator<Edge> edges(final Object... edgeIds) { return Collections.emptyIterator(); }
Example 19
Source Project: Bats File: ValueExpressions.java License: Apache License 2.0 | 4 votes |
@Override public Iterator<LogicalExpression> iterator() { return Collections.emptyIterator(); }
Example 20
Source Project: ReactFX File: LL.java License: BSD 2-Clause "Simplified" License | votes |
@Override public Iterator<T> iterator() { return Collections.emptyIterator(); }