Java Stream.filter方法代碼示例

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Get stream of entity types to based on given strategy, relation row will be created for each one
 *
 * @param instance instance to get types from
 * @return stream of entity types based on given strategy, relation row will be created for each one
 */
private Stream<Integer> getRelationEntityTypes(Instance instance) {
    RelationSchemaStrategy strategy = config.getSchemaStrategy();
    // in default, return all types
    Stream<Integer> types = instance.getTypes().stream();
    if (strategy == Predicates || strategy == SingleTable) {
        // create row for one type only
        types = types.limit(1);
    } else if (config.isRootTypesOnly()) {
        // filter out types that have a superclass to ensure relations are only created between root classes
        if (instance.getTypes().size() > 1) {
            types = types.filter(type -> !classGraph.hasSuperClasses(type));
        }
    }
    return types;
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * From a list of potential states, generate the list of intersecting
 * states. This means all state intervals that actually cross the target
 * timestamp.
 *
 * Note that we've already verified one of the start/end time for back/forth
 * navigation when generating the potential states, this method only needs
 * to check the other bound.
 */
private static List<StateRectangle> getIntersectingStates(List<StateRectangle> potentialStates,
        long targetTimestamp, boolean forward) {

    Stream<StateRectangle> intersectingStates = potentialStates.stream();
    if (forward) {
        intersectingStates = intersectingStates.filter(rect -> {
            long start = rect.getStateInterval().getStartEvent().getTimestamp();
            return (targetTimestamp >= start);
        });
    } else {
        intersectingStates = intersectingStates.filter(rect -> {
            long end = rect.getStateInterval().getEndEvent().getTimestamp();
            return (targetTimestamp <= end);
        });
    }
    return intersectingStates.collect(Collectors.toList());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
Stream<PsiClass> classStream() {
    if (context.isValid()) {
        Stream<PsiClass> stream = StreamSupport.stream(
                AnnotatedElementsSearch.searchPsiClasses(
                        context.getConfigAnnotationClass(),
                        GlobalSearchScope.allScope(context.getProject())).spliterator(),
                false);
        Predicate<PsiClass> filter = context.getFilter();
        if (filter != null) {
            stream = stream.filter(filter);
        }
        return stream;
    } else {
        return Stream.empty();
    }
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
Set<WordUsage> getSentences(List<Sentence> sentences, Function<Token, String> customMapper,
                             Predicate<String> customFilter) {
    final Map<String, Set<String>> words = new HashMap<>();
    for (Sentence sentence: sentences) {
        Stream<String> wordsStream = sentence.getTokens().stream()
                .filter(t -> t.getToken().matches(WORD_REGEX))
                .filter(t -> getTags().contains(t.getTag()))
                .filter(t -> !isUpperCase(t.getToken().charAt(0)))
                .filter(t -> t.getProb() >= config.getVocabularyProb())
                .map(customMapper);

        if (customFilter != null) {
            wordsStream = wordsStream.filter(customFilter);
        }

        wordsStream.forEach(word -> {
            final Set<String> wordSentences = words.getOrDefault(word, new HashSet<>());
            wordSentences.add(sentence.getSentence());
            words.put(word, wordSentences);
        });
    }

    return words.entrySet().stream()
            .sorted(reverseOrder(comparingInt(e -> e.getValue().size())))
            .map(e -> new WordUsage(e.getKey(), e.getValue())).collect(toSet());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
@Override
public List<Movie> retrieve(Query query) throws PersistException {
    List<Movie> movies = getMovies();
    Stream<Movie> stream = movies.stream();
    
    // filter
    if (query.hasFilters() || query.getSearch() != null) {
        stream = stream.filter(movie -> query.match(new JsonMatcher(movie.toJson())));
    }
    
    // sort
    if ((query.getSort() != null && !"title".equals(query.getSort())) || query.isDescending()) {
        stream = stream.sorted(new JsonableComparator(query, (j1, j2) -> {
            return getSortTitle(j1).compareToIgnoreCase(getSortTitle(j2));
        }));
    }
    
    // paginate
    if (query.getStart() > 0)
        stream = stream.skip(query.getStart());
    if (query.getMax() != Query.MAX_ALL)
        stream = stream.limit(query.getMax());
    
    return stream.collect(Collectors.toList());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public static Stream<Activation> select(INeuron.ThreadState th, INeuron n, Integer rid, Range r, Range.Relation rr, InterprNode o, InterprNode.Relation or) {
    Stream<Activation> results;
    int s = th.activations.size();

    Node node = n.node.get();
    if(s == 0) return Stream.empty();
    else if(s == 1) {
        results = th.activations
                .values()
                .stream();
    } else if(rid != null) {
        Key bk = new Key(node, Range.MIN, rid, InterprNode.MIN);
        Key ek = new Key(node, Range.MAX, rid, InterprNode.MAX);

        if(th.activationsRid != null) {
            results = th.activationsRid.subMap(bk, true, ek, true)
                    .values()
                    .stream();
        } else return Stream.empty();
    } else {
        if(rr == null) {
            results = th.activations.values()
                    .stream();
        } else {
            return getActivationsByRange(th, n, rid, r, rr, o, or);
        }
    }

    return results.filter(act -> act.filter(node, rid, r, rr, o, or));
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public RaftServerImpl getLeader(RaftGroupId groupId) {
  Stream<RaftServerImpl> stream = getServerAliveStream();
  if (groupId != null) {
    stream = stream.filter(s -> groupId.equals(s.getGroupId()));
  }
  return getLeader(stream);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
@Test
public void testWeatherServiceLazy(){
    /**
     * Arrange WeatherService --> WeatherWebApi --> Countify --> FileRequest
     */
    ICounter<String, CompletableFuture<Stream<String>>> req = Countify.of(new FileRequest()::getContent);
    WeatherService api = new WeatherService(new WeatherWebApi(req::apply));
    /**
     * Act and Assert
     */
    Stream<Location> locals = api.search("Porto").join();
    assertEquals(1, req.getCount());
    locals = locals.filter(l -> l.getLatitude() > 0 );
    assertEquals(1, req.getCount());
    /**
     * When we get the first item from Stream we are instantiating a new
     * Location object and thus requesting its last 30 days past weather.
     */
    Location loc = locals.findFirst().get();
    assertEquals(2, req.getCount());
    Stream<WeatherInfo> infos = loc.getPastWeather(of(2017,02,01), of(2017,02,28));
    assertEquals(3, req.getCount());
    infos = infos.filter(info -> info.getDescription().toLowerCase().contains("sun"));
    Stream<Integer> temps = infos.map(WeatherInfo::getTempC);
    temps = temps.distinct();
    assertEquals(3, req.getCount());
    assertEquals(5, temps.count()); // iterates all items
    assertEquals(3, req.getCount());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
@Test
public void testWeatherServiceLazy(){
    /**
     * Arrange WeatherService --> WeatherWebApi --> Countify --> FileRequest
     */
    ICounter<String, Stream<String>> req = Countify.of(new FileRequest()::getContent);
    WeatherService api = new WeatherService(new WeatherWebApi(req::apply));
    /**
     * Act and Assert
     */
    Stream<Location> locals = api.search("Porto");
    assertEquals(1, req.getCount());
    locals = locals.filter(l -> l.getLatitude() > 0 );
    assertEquals(1, req.getCount());
    Location loc = locals.findFirst().get();
    assertEquals(1, req.getCount());
    Stream<WeatherInfo> infos = loc.getPastWeather(of(2017,02,01), of(2017,02,28));
    assertEquals(2, req.getCount());
    infos = infos.filter(info -> info.getDescription().toLowerCase().contains("sun"));
    Stream<Integer> temps = infos.map(WeatherInfo::getTempC);
    temps = temps.distinct();
    assertEquals(2, req.getCount());
    /**
     * When we iterate over the pastWeather then we make one more request
     */
    assertEquals(5, temps.count()); // iterates all items
    assertEquals(2, req.getCount());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
private QueryBuilder getVertexFilter(EnumSet<ElasticsearchDocumentType> elementTypes) {
    List<QueryBuilder> filters = new ArrayList<>();
    List<String> edgeLabels = getParameters().getEdgeLabels();
    String[] edgeLabelsArray = edgeLabels == null || edgeLabels.size() == 0
            ? null
            : edgeLabels.toArray(new String[edgeLabels.size()]);
    Stream<EdgeInfo> edgeInfos = stream(sourceVertex.getEdgeInfos(
            direction,
            edgeLabelsArray,
            getParameters().getAuthorizations()
    ));
    if (otherVertexId != null) {
        edgeInfos = edgeInfos.filter(ei -> ei.getVertexId().equals(otherVertexId));
    }
    if (getParameters().getIds().size() > 0) {
        edgeInfos = edgeInfos.filter(ei -> getParameters().getIds().contains(ei.getVertexId()));
    }
    String[] ids = edgeInfos.map(EdgeInfo::getVertexId).toArray(String[]::new);

    if (elementTypes.contains(ElasticsearchDocumentType.VERTEX)) {
        filters.add(QueryBuilders.idsQuery().addIds(ids));
    }

    if (elementTypes.contains(ElasticsearchDocumentType.VERTEX_EXTENDED_DATA)) {
        for (String vertexId : ids) {
            filters.add(
                    QueryBuilders.boolQuery()
                            .must(QueryBuilders.termQuery(Elasticsearch5SearchIndex.ELEMENT_TYPE_FIELD_NAME, ElasticsearchDocumentType.VERTEX_EXTENDED_DATA.getKey()))
                            .must(QueryBuilders.termQuery(Elasticsearch5SearchIndex.EXTENDED_DATA_ELEMENT_ID_FIELD_NAME, vertexId)));
        }
    }

    return orFilters(filters);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
@Override
public Object[] getElements(Object inputElement) {
    Stream<PgObjLocation> stream = sqlEditor.getParser().getObjsForEditor(
            sqlEditor.getEditorInput()).stream().filter(
                    e -> e.getAction() != StatementActions.NONE);
    if (filterDangerous) {
        stream = stream.filter(PgObjLocation::isDanger);
    }
    if (sortStatements) {
        stream = stream.sorted((a,b) -> a.getObjName().compareTo(b.getObjName()));
    }

    return stream.map(Segments::new).toArray();
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
@Override
public List<JobHistory> getJobsHistory(final int count,final String operation,final String status) {
	final List<JobHistory> result = new ArrayList<>(count);

	NodeRef node = monitorStorage.getOrCreateMonitorJobsContainer();
	final List<ChildAssociationRef> childAssocs = nodeService.getChildAssocs(node);
	Collections.reverse(childAssocs);

	Stream<ChildAssociationRef> streamChildrenAssocs = childAssocs.stream();
	
	if (operation != null && !operation.isEmpty()) {
		streamChildrenAssocs = streamChildrenAssocs.filter(ch -> ((String) nodeService.getProperty(ch.getChildRef(), MonitorModel.PROP_OPERATION)).equalsIgnoreCase(operation));
	}
	if (status != null && !status.isEmpty()) {
		streamChildrenAssocs = streamChildrenAssocs.filter(ch -> ((String) nodeService.getProperty(ch.getChildRef(), MonitorModel.PROP_STATUS)).equalsIgnoreCase(status));
	}

	final List<ChildAssociationRef> childAssocsLimit = streamChildrenAssocs.limit(count).collect(Collectors.toList());

	for (ChildAssociationRef child : childAssocsLimit) {
		final NodeRef nodeRef = child.getChildRef();
		final String nodeStatus = INSTANCE.convert(String.class, nodeService.getProperty(nodeRef, MonitorModel.PROP_STATUS));
		final Date date = INSTANCE.convert(Date.class, nodeService.getProperty(nodeRef, ContentModel.PROP_CREATED));
		final String operHist = INSTANCE.convert(String.class, nodeService.getProperty(nodeRef, MonitorModel.PROP_OPERATION));		
		result.add(new JobHistory(operHist, nodeRef, nodeStatus, date));
	}
	return result;
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public Collection<Meter> meters() {
    Stream<Entry<Id, Meter>> entryStream =
            meterMap.entrySet().stream().filter(e -> e.getKey().getName().equals(name));

    if (!tags.isEmpty()) {
        entryStream = entryStream.filter(e -> {
            final List<Tag> idTags = new ArrayList<>();
            e.getKey().getTags().forEach(idTags::add);
            return idTags.containsAll(tags);
        });
    }

    return entryStream.map(Map.Entry::getValue)
        .collect(Collectors.toList());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
private static <R> Stream<Match<R>> successfulCases(
        List<Matcher<R>> cases,
        SortedSetMultimap<Class<?>, Indexed<Matcher<R>>> matchersByScopeType,
        Object object
) {
    Stream<Matcher<R>> potentialMatchersInOrder = potentialMatchersInOrder(cases, matchersByScopeType, object);
    Stream<Match<R>> caseResults = potentialMatchersInOrder
            .map(matcher -> matcher.match(object));
    return caseResults.filter(Match::isPresent);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Returns an immutable set of nodes that can be used to instantiate the
 * specified class. This method uses reflection to scan over all the classes
 * fields and constructors to determine what dependencies every constructor
 * comes with. If at least one constructor has the
 * {@link Inject}-annotation, then only constructors with that annotation
 * will be considered.
 *
 * @param <T>        the type
 * @param clazz      the class to get nodes for
 * @param qualifier  the qualifier
 *
 * @return           immutable set of nodes for the given class
 */
static <T> Set<Node<?>> findNodes(Class<T> clazz, String qualifier) {

    // Determine if there are any members that need to be injected.
    final Set<String> dependencies = unmodifiableSet(traverseFields(clazz)
        .filter(f -> f.getAnnotation(Inject.class) != null)
        .map(f -> ofNullable(f.getAnnotation(Inject.class))
            .map(Inject::value).filter(StringUtil::notEmpty)
            .orElseGet(() -> f.getType().getName())
        ).collect(toSet())
    );

    // If the specified type has at least one annotated constructor, we
    // should only look at them. Otherwise, consider all constructors
    // candidates for injection.
    Stream<Constructor<?>> constructors = Stream.of(clazz.getDeclaredConstructors());
    if (Stream.of(clazz.getDeclaredConstructors()).anyMatch(INJECTABLE)) {
        constructors = constructors.filter(INJECTABLE);
    }

    // Compute the necessary dependencies for every constructor and add
    // them to the map.
    final Set<Node<?>> nodes = new LinkedHashSet<>();
    constructors.forEach(constr -> {
        final Set<String> deps = new HashSet<>(dependencies);

        Stream.of(constr.getParameters())
            .map(p -> ofNullable(p.getAnnotation(Inject.class))
                .map(Inject::value).filter(StringUtil::notEmpty)
                .orElseGet(() -> p.getType().getName())
            ).forEach(deps::add);

        nodes.add(new NodeImpl<>(
            qualifier,
            unmodifiableSet(deps),
            constr
        ));
    });

    return unmodifiableSet(nodes);
}