List of usage examples for java.util.stream Stream empty
public static <T> Stream<T> empty()
From source file:com.homeadvisor.kafdrop.service.CuratorKafkaMonitor.java
private Map<String, TopicVO> getTopicMetadata(String... topics) { if (kafkaVersion.compareTo(new Version(0, 9, 0)) >= 0) { return retryTemplate .execute(context -> brokerChannel(null).execute(channel -> getTopicMetadata(channel, topics))); } else {// ww w . j a v a2s . com Stream<String> topicStream; if (topics == null || topics.length == 0) { topicStream = Optional.ofNullable(topicTreeCache.getCurrentChildren(ZkUtils.BrokerTopicsPath())) .map(Map::keySet).map(Collection::stream).orElse(Stream.empty()); } else { topicStream = Stream.of(topics); } return topicStream.map(this::getTopicZkData).filter(Objects::nonNull) .collect(Collectors.toMap(TopicVO::getName, topic -> topic)); } }
From source file:org.codice.ddf.configuration.migration.ImportMigrationManagerImplTest.java
@Test public void testConstructorWhenZipFileNotFound() throws Exception { thrown.expect(MigrationException.class); thrown.expectCause(Matchers.instanceOf(FileNotFoundException.class)); new ImportMigrationManagerImpl(report, exportFile, Stream.empty()); }
From source file:org.opensingular.flow.persistence.service.AbstractHibernatePersistenceService.java
@Override public PROCESS_VERSION saveProcessVersion(PROCESS_VERSION processVersion) { SessionWrapper sw = getSession();/*from w w w. j a v a 2s . c om*/ sw.saveOrUpdate(processVersion.getProcessDefinition()); sw.saveOrUpdate(processVersion); sw.saveOrUpdate(processVersion.getVersionTasks().stream().map(tv -> tv.getTaskDefinition())); sw.saveOrUpdate(processVersion.getVersionTasks().stream() .flatMap(tv -> tv.getTaskDefinition().getRolesTask() != null ? tv.getTaskDefinition().getRolesTask().stream() : Stream.empty())); sw.saveOrUpdate(processVersion.getVersionTasks()); sw.saveOrUpdate(processVersion.getVersionTasks().stream().flatMap(tv -> tv.getTransitions().stream())); sw.refresh(processVersion.getProcessDefinition()); return retrieveProcessVersionByCod(processVersion.getCod()); }
From source file:org.codice.ddf.configuration.migration.ImportMigrationManagerImplTest.java
@Test public void testConstructorWhenUnableToProcessMetadata() throws Exception { final IOException ioe = new IOException("testing"); Mockito.doThrow(ioe).when(zip).getInputStream(zipEntry); thrown.expect(MigrationException.class); thrown.expectCause(Matchers.sameInstance(ioe)); new ImportMigrationManagerImpl(report, exportFile, Stream.empty(), zip); }
From source file:org.springframework.cloud.dataflow.server.stream.AppDeployerStreamDeployer.java
@Override public Page<AppStatus> getAppStatuses(Pageable pageable) throws ExecutionException, InterruptedException { Iterable<StreamDefinition> streamDefinitions = this.streamDefinitionRepository.findAll(); Iterable<StreamDeployment> streamDeployments = this.streamDeploymentRepository.findAll(); List<String> appDeployerStreams = new ArrayList<>(); for (StreamDeployment streamDeployment : streamDeployments) { appDeployerStreams.add(streamDeployment.getStreamName()); }/*w w w .j ava2 s .c om*/ List<StreamDefinition> appDeployerStreamDefinitions = new ArrayList<>(); for (StreamDefinition streamDefinition : streamDefinitions) { if (appDeployerStreams.contains(streamDefinition.getName())) { appDeployerStreamDefinitions.add(streamDefinition); } } // First build a sorted list of deployment id's so that we have a predictable paging order. List<String> deploymentIds = appDeployerStreamDefinitions.stream() .flatMap(sd -> sd.getAppDefinitions().stream()).flatMap(sad -> { String key = DeploymentKey.forStreamAppDefinition(sad); String id = this.deploymentIdRepository.findOne(key); return id != null ? Stream.of(id) : Stream.empty(); }).sorted(String::compareTo).collect(Collectors.toList()); // Running this this inside the FJP will make sure it is used by the parallel stream // Skip first items depending on page size, then take page and discard rest. List<AppStatus> content = this.forkJoinPool.submit(() -> deploymentIds.stream() .skip(pageable.getPageNumber() * pageable.getPageSize()).limit(pageable.getPageSize()).parallel() .map(appDeployer::status).collect(Collectors.toList())).get(); return new PageImpl<>(content, pageable, deploymentIds.size()); }
From source file:org.codice.ddf.configuration.migration.ImportMigrationManagerImplTest.java
@Test public void testConstructorWhenZipIsOfInvalidVersion() throws Exception { zipEntry = getMetadataZipEntry(zip, Optional.of(VERSION), Optional.of(PRODUCT_VERSION)); thrown.expect(MigrationException.class); thrown.expectMessage("unsupported exported version"); new ImportMigrationManagerImpl(report, exportFile, Stream.empty(), zip); }
From source file:org.icgc.dcc.portal.pql.convert.FiltersConverter.java
private static <T> Stream<T> tail(@NonNull List<T> list) { val size = list.size(); return (size < 2) ? Stream.empty() : IntStream.range(1, size).boxed().map(i -> list.get(i)); }
From source file:com.uber.hoodie.common.util.TestCompactionUtils.java
private Map<String, Pair<String, HoodieCompactionOperation>> generateExpectedCompactionOperations( List<HoodieCompactionPlan> plans) { return plans.stream().flatMap(plan -> { if (plan.getOperations() != null) { return plan.getOperations().stream() .map(op -> Pair.of(op.getFileId(), Pair.of(op.getBaseInstantTime(), op))); }/*from ww w . ja v a2 s . co m*/ return Stream.empty(); }).collect(Collectors.toMap(Pair::getKey, Pair::getValue)); }
From source file:org.apache.tinkerpop.gremlin.neo4j.structure.Neo4jGraph.java
@Override public Iterator<Edge> edges(final Object... edgeIds) { this.tx().readWrite(); final Predicate<Neo4jRelationship> relationshipPredicate = this.trait.getRelationshipPredicate(); if (0 == edgeIds.length) { return IteratorUtils.stream(this.getBaseGraph().allRelationships()).filter(relationshipPredicate) .map(relationship -> (Edge) new Neo4jEdge(relationship, this)).iterator(); } else {/*from ww w.j a v a 2 s .c om*/ ElementHelper.validateMixedElementIds(Edge.class, edgeIds); return Stream.of(edgeIds).map(id -> { if (id instanceof Number) return ((Number) id).longValue(); else if (id instanceof String) return Long.valueOf(id.toString()); else if (id instanceof Edge) { return (Long) ((Edge) id).id(); } else throw new IllegalArgumentException("Unknown edge id type: " + id); }).flatMap(id -> { try { return Stream.of(this.baseGraph.getRelationshipById(id)); } catch (final RuntimeException e) { if (Neo4jHelper.isNotFound(e)) return Stream.empty(); throw e; } }).filter(relationshipPredicate).map(relationship -> (Edge) new Neo4jEdge(relationship, this)) .iterator(); } }
From source file:com.cloudera.oryx.app.serving.als.model.ALSServingModel.java
public Stream<Pair<String, Double>> topN(CosineDistanceSensitiveFunction scoreFn, ObjDoubleToDoubleFunction<String> rescoreFn, int howMany, Predicate<String> allowedPredicate) { int[] candidateIndices = lsh.getCandidateIndices(scoreFn.getTargetVector()); List<Callable<Stream<Pair<String, Double>>>> tasks = new ArrayList<>(candidateIndices.length); for (int partition : candidateIndices) { if (Y[partition].size() > 0) { tasks.add(LoggingCallable.log(() -> { TopNConsumer consumer = new TopNConsumer(howMany, scoreFn, rescoreFn, allowedPredicate); Y[partition].forEach(consumer); return consumer.getTopN(); }));//from w w w . j a v a2 s . co m } } int numTasks = tasks.size(); if (numTasks == 0) { return Stream.empty(); } Stream<Pair<String, Double>> stream; if (numTasks == 1) { try { stream = tasks.get(0).call(); } catch (Exception e) { throw new IllegalStateException(e); } } else { try { stream = executor.invokeAll(tasks).stream().map(future -> { try { return future.get(); } catch (InterruptedException e) { throw new IllegalStateException(e); } catch (ExecutionException e) { throw new IllegalStateException(e.getCause()); } }).reduce(Stream::concat).get(); } catch (InterruptedException e) { throw new IllegalStateException(e); } } return stream.sorted(Pairs.orderBySecond(Pairs.SortOrder.DESCENDING)).limit(howMany); }