List of usage examples for com.google.common.collect Iterators emptyIterator
@Deprecated public static <T> UnmodifiableIterator<T> emptyIterator()
From source file:gobblin.data.management.copy.hive.HiveDataset.java
/** * Finds all files read by the table and generates CopyableFiles. * For the specific semantics see {@link HiveCopyEntityHelper#getCopyEntities}. *///from www .j a v a2 s . co m @Override public Iterator<FileSet<CopyEntity>> getFileSetIterator(FileSystem targetFs, CopyConfiguration configuration, Comparator<FileSet<CopyEntity>> prioritizer, PushDownRequestor<FileSet<CopyEntity>> requestor) throws IOException { if (!canCopyTable()) { return Iterators.emptyIterator(); } try { List<FileSet<CopyEntity>> fileSetList = Lists .newArrayList(new HiveCopyEntityHelper(this, configuration, targetFs) .getCopyEntities(configuration, prioritizer, requestor)); Collections.sort(fileSetList, prioritizer); return fileSetList.iterator(); } catch (IOException ioe) { log.error("Failed to copy table " + this.table, ioe); return Iterators.emptyIterator(); } }
From source file:eu.numberfour.n4js.ui.internal.EclipseBasedN4JSWorkspace.java
@Override public Iterator<URI> getArchiveIterator(final URI archiveLocation, String archiveRelativeLocation) { ZipInputStream stream = null; try {/*from w ww . j a v a 2 s . co m*/ stream = getArchiveStream(archiveLocation); Iterator<ZipEntry> entries = getArchiveIterator(stream, archiveRelativeLocation); return toArchiveURIs(archiveLocation, entries); } catch (CoreException | IOException e) { return Iterators.emptyIterator(); } finally { if (stream != null) { try { stream.close(); } catch (IOException e) { // ignore } } } }
From source file:org.richfaces.ui.toggle.tabPanel.AbstractTab.java
/** * If the VisitContext is not the RenderExtendedVisitContext, return the usual FacetsAndChildren iterator. * Otherwise return only the Facet iterator when a child visit is not required. * * This is useful to not render the tab contents when an item is not visible, while still visiting the header facets. * * @param visitContext The VisitContext of the component tree visit. *//*from w w w . j a v a2s . co m*/ public static Iterator<UIComponent> getVisitableChildren(UIComponent component, VisitContext visitContext) { Iterator<UIComponent> kids; if (RenderExtendedVisitContext.isRenderExtendedVisitContext(visitContext) && component instanceof VisitChildrenRejectable && !((VisitChildrenRejectable) component).shouldVisitChildren()) { if (component.getFacetCount() > 0) { kids = component.getFacets().values().iterator(); } else { kids = Iterators.emptyIterator(); } } else { kids = component.getFacetsAndChildren(); } return kids; }
From source file:org.apache.jackrabbit.oak.spi.security.authentication.external.impl.principal.ExternalGroupPrincipalProvider.java
@Nonnull @Override/*www .j a v a2 s . co m*/ public Iterator<? extends Principal> findPrincipals(@Nullable String nameHint, int searchType) { if (PrincipalManager.SEARCH_TYPE_NOT_GROUP != searchType) { Result result = findPrincipals(Strings.nullToEmpty(nameHint), false); if (result != null) { return Iterators.filter(new GroupPrincipalIterator(nameHint, result), Predicates.notNull()); } } return Iterators.emptyIterator(); }
From source file:eu.esdihumboldt.hale.ui.instancevalidation.report.InstanceValidationReportDetailsPage.java
/** * Returns a valid instance selection for the current selection of the tree * viewer. Returns <code>null</code> if there is none. * // w w w.j av a 2 s. c om * @return a valid instance selection for the current selection of the tree * viewer or <code>null</code> */ private InstanceSelection getValidSelection() { ISelection viewerSelection = treeViewer.getSelection(); if (!(viewerSelection instanceof ITreeSelection) || viewerSelection.isEmpty()) return null; ITreeSelection treeSelection = (ITreeSelection) treeViewer.getSelection(); TreePath firstPath = treeSelection.getPaths()[0]; // XXX use all paths // instead of first // only? InstanceValidationMessage firstMessage; Iterator<InstanceValidationMessage> restIter; if (firstPath.getLastSegment() instanceof InstanceValidationMessage) { firstMessage = (InstanceValidationMessage) firstPath.getLastSegment(); restIter = Iterators.emptyIterator(); } else { Collection<InstanceValidationMessage> messages = contentProvider .getMessages(treeSelection.getPaths()[0]); if (messages.isEmpty()) return null; // shouldn't happen, but doesn't really matter restIter = messages.iterator(); firstMessage = restIter.next(); } InstanceService is = (InstanceService) PlatformUI.getWorkbench().getService(InstanceService.class); // check first message for valid instance reference if (firstMessage.getInstanceReference() == null || is.getInstance(firstMessage.getInstanceReference()) == null) return null; Set<InstanceReference> references = new HashSet<InstanceReference>(); references.add(firstMessage.getInstanceReference()); while (restIter.hasNext()) references.add(restIter.next().getInstanceReference()); return new DefaultInstanceSelection(references.toArray()); }
From source file:alluxio.master.meta.DefaultMetaMaster.java
@Override public Iterator<JournalEntry> getJournalEntryIterator() { return Iterators.emptyIterator(); }
From source file:org.apache.jackrabbit.oak.security.user.UserPrincipalProvider.java
@Nonnull @Override/*from ww w .j av a2 s . com*/ public Iterator<? extends Principal> findPrincipals(final String nameHint, final int searchType) { try { AuthorizableType type = AuthorizableType.getType(searchType); StringBuilder statement = new StringBuilder() .append(QueryUtil.getSearchRoot(type, config.getParameters())).append("//element(*,") .append(QueryUtil.getNodeTypeName(type)).append(')').append("[jcr:like(@rep:principalName,'") .append(buildSearchPattern(nameHint)).append("')]"); Result result = root.getQueryEngine().executeQuery(statement.toString(), javax.jcr.query.Query.XPATH, NO_BINDINGS, namePathMapper.getSessionLocalMappings()); Iterator<Principal> principals = Iterators.filter( Iterators.transform(result.getRows().iterator(), new ResultRowToPrincipal()), Predicates.notNull()); if (matchesEveryone(nameHint, searchType)) { principals = Iterators.concat(principals, Iterators.singletonIterator(EveryonePrincipal.getInstance())); return Iterators.filter(principals, new EveryonePredicate()); } else { return principals; } } catch (ParseException e) { log.debug(e.getMessage()); return Iterators.emptyIterator(); } }
From source file:org.geogit.osm.internal.history.HistoryDownloader.java
private Iterator<Change> parseChanges(Supplier<Optional<File>> file) { ChangesetContentsScanner scanner = new ChangesetContentsScanner(); final Optional<File> changesFile; try {//from ww w .ja va 2 s. com changesFile = file.get(); } catch (RuntimeException e) { Throwable cause = e.getCause(); if (cause instanceof FileNotFoundException) { return Iterators.emptyIterator(); } throw Throwables.propagate(e); } if (!changesFile.isPresent()) { return Iterators.emptyIterator(); } final File actualFile = changesFile.get(); final InputStream stream = openStream(actualFile); final Iterator<Change> changes; try { changes = scanner.parse(stream); } catch (XMLStreamException e) { throw Throwables.propagate(e); } return new AbstractIterator<Change>() { @Override protected Change computeNext() { if (!changes.hasNext()) { Closeables.closeQuietly(stream); if (!preserveFiles) { actualFile.delete(); actualFile.getParentFile().delete(); } return super.endOfData(); } return changes.next(); } }; }
From source file:com.android.tools.lint.detector.api.JavaContext.java
@NonNull public static Iterator<Expression> getParameters(@NonNull Node call) { if (call instanceof MethodInvocation) { return ((MethodInvocation) call).astArguments().iterator(); } else if (call instanceof ConstructorInvocation) { return ((ConstructorInvocation) call).astArguments().iterator(); } else if (call instanceof EnumConstant) { return ((EnumConstant) call).astArguments().iterator(); } else {/*from w ww .j a v a 2s . c o m*/ return Iterators.emptyIterator(); } }
From source file:eu.numberfour.n4js.resource.N4JSUnloader.java
/** * Traverse the contents of the object that is contained in the {@link ObjectToFragment}. The string builder is used * as an accumulating parameter. That is, during the traversal it will be used and trimmed again. This allows to * reuse the underlying char array which is already copied when the fragment is turned into a string. * * The fragments use the very same notation as described in * {@link InternalEObject#eURIFragmentSegment(EStructuralFeature, EObject)}. * * The implementation from {@link ResourceImpl} uses a {@link SegmentSequence} rather than a {@link StringBuilder}. * Since we have to concatenate the string in the end anyway. *///from w ww. j ava 2 s.c om private static Iterator<ObjectToFragment> getAllProperContents(ObjectToFragment eObject, final StringBuilder result) { // we inherit from the AbstractTreeIterator which will help us getting a proper pre-order traversal return new AbstractTreeIterator<ObjectToFragment>(eObject, false /* don't resolve containment proxies */) { @Override public Iterator<ObjectToFragment> getChildren(Object parent) { final EObject current = ((ObjectToFragment) parent).object; final EStructuralFeature[] containments = containmentFeatures(current); if (containments == null || containments.length == 0) { // no containment features found, exit return Iterators.emptyIterator(); } // we have at least one containment feature - append the fragment delimiter '/' result.append('/'); // and concatenate all the iterators for the children return Iterators.concat(getFeatureIterators(current, containments)); } /** * Returns an iterator of iterators. Each nested iterator covers a single containment feature. If the * feature is multi valued, the nested iterator has as many values as are set on the feature. */ private Iterator<Iterator<ObjectToFragment>> getFeatureIterators(EObject current, EStructuralFeature[] containments) { return new AbstractIterator<Iterator<ObjectToFragment>>() { /** * The length of the string builder before something was added by this traversing iterator. */ private final int prevLength = result.length(); private int featureIdx = 0; @Override protected Iterator<ObjectToFragment> computeNext() { while (featureIdx < containments.length) { EStructuralFeature containment = containments[featureIdx]; featureIdx++; // only consider features that have values if (current.eIsSet(containment)) { // reset the string builder result.setLength(prevLength); // append the @ sign and the feature name // '@<feature-name>' result.append('@').append(containment.getName()); // compute the contained values return newValueIterator(containment); } } return endOfData(); } /** * Returns an iterator for the values that are assigned to the given containment feature. */ private Iterator<ObjectToFragment> newValueIterator(EStructuralFeature feature) { if (feature.isMany()) { // add the dot as the delimiter between feature name and index in the list result.append('.'); // compute the value indexes return newManyValueIterator((List<?>) current.eGet(feature)); } else { // no dot is added for single valued features return newSingleValueIterator((EObject) current.eGet(feature)); } } /** * Finalize the fragment for the given instance and return a singleton iterator for it. */ private Iterator<ObjectToFragment> newSingleValueIterator(EObject value) { ObjectToFragment objectToFragment = new ObjectToFragment(value, result.toString()); return Iterators.singletonIterator(objectToFragment); } /** * Traverse the list of values and return the feature indexes along with the values. */ private AbstractIterator<ObjectToFragment> newManyValueIterator(final List<?> values) { return new AbstractIterator<ObjectToFragment>() { /** * The length of the string builder before something was added by this traversing iterator. */ private final int prevLengthBeforeIdx = result.length(); /** * The index in the value list. */ private int valueIdx = 0; @Override protected ObjectToFragment computeNext() { if (valueIdx < values.size()) { EObject value = (EObject) values.get(valueIdx); result.setLength(prevLengthBeforeIdx); result.append(valueIdx); valueIdx++; return new ObjectToFragment(value, result.toString()); } return endOfData(); } }; } }; } private EStructuralFeature[] containmentFeatures(final EObject current) { return ((EClassImpl.FeatureSubsetSupplier) current.eClass().getEAllStructuralFeatures()) .containments(); } }; }