Example usage for java.util.stream Collectors toMap

List of usage examples for java.util.stream Collectors toMap

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Introduction

In this page you can find the example usage for java.util.stream Collectors toMap.

Prototype

public static <T, K, U> Collector<T, ?, Map<K, U>> toMap(Function<? super T, ? extends K> keyMapper,
        Function<? super T, ? extends U> valueMapper)

Source Link

Document

Returns a Collector that accumulates elements into a Map whose keys and values are the result of applying the provided mapping functions to the input elements.

Usage

From source file:ru.anr.base.BaseParent.java

/**
 * A short-cut method for simple mapping from a collection to a map
 * /*from www.j a v a  2s. c  o  m*/
 * @param collection
 *            A collection
 * @param keyMapper
 *            A key mapper
 * @param valueMapper
 *            A value mapper
 * @return A new created map
 * 
 * @param <T>
 *            The type of collection items
 * @param <K>
 *            The type of map keys
 * @param <U>
 *            The type of map values
 */
public static <T, K, U> Map<K, U> toMap(Collection<T> collection, Function<? super T, ? extends K> keyMapper,
        Function<? super T, ? extends U> valueMapper) {

    return collection.stream().collect(Collectors.toMap(keyMapper, valueMapper));
}

From source file:com.thinkbiganalytics.nifi.rest.support.NifiPropertyUtil.java

/**
 * Groups the properties by their {@see NifiProperty#getIdKey}
 * @param properties the properties to inspect
 * @return a map with the property idKey (the processgroup+processorId+propertyKey, property)
 *//* www  .  j  av  a2 s  .co m*/
public static Map<String, NifiProperty> groupPropertiesByIdKey(List<NifiProperty> properties) {
    Map<String, NifiProperty> map = new HashMap();
    if (properties != null) {
        map = properties.stream().collect(Collectors.toMap(p -> p.getIdKey(), p -> p));
    }
    return map;
}

From source file:com.ggvaidya.scinames.model.Project.java

/**
 * Returns a list of dataset rows across all datasets for a particular name.
 * /*from   ww  w  .j  a  va 2  s  . c  o  m*/
 * Note that while the API signature allows for duplicate rows to be summarized, this hasn't
 * yet been implemented: we'll return a unique dataset row from multiple datasets even where
 * the data in those rows is identical.
 * 
 * @param n The name to identify across all datasets.
 * @return A Map<DatasetRow, Set<Dataset>> indicating rows to be returned.
 */
public Map<DatasetRow, Set<Dataset>> getRowsForName(Name n) {
    Map<Dataset, Set<DatasetRow>> timepointsPerRow = getDatasets().stream()
            .collect(Collectors.toMap(tp -> tp, tp -> tp.getRowsByName(n)));

    final Map<DatasetRow, Set<Dataset>> results = new HashMap<>();
    for (Dataset tp : timepointsPerRow.keySet()) {
        Set<DatasetRow> rowsForTP = timepointsPerRow.get(tp);

        rowsForTP.forEach(r -> {
            if (!results.containsKey(r))
                results.put(r, new HashSet<>());

            results.get(r).add(tp);
        });
    }

    return results;
}

From source file:nu.yona.server.analysis.service.ActivityService.java

private <T extends IntervalActivity> Map<ZonedDateTime, Set<T>> mapToZonedDateTime(
        Map<LocalDate, Set<T>> intervalActivityEntitiesByLocalDate) {
    return intervalActivityEntitiesByLocalDate.entrySet().stream()
            .collect(Collectors.toMap(e -> e.getValue().iterator().next().getStartTime(), Map.Entry::getValue));
}

From source file:com.epam.catgenome.manager.FeatureIndexManager.java

/**
 * Filer chromosomes that contain variations, specified by filter
 *
 * @param filterForm a {@code VcfFilterForm} to filter out chromosomes
 * @return a {@code List} of {@code Chromosome} that corresponds to specified filter
 * @throws IOException//ww  w  . j  a  v a2 s  . com
 */
public List<Chromosome> filterChromosomes(VcfFilterForm filterForm) throws IOException {
    Assert.isTrue(filterForm.getVcfFileIds() != null && !filterForm.getVcfFileIds().isEmpty(),
            MessageHelper.getMessage(MessagesConstants.ERROR_NULL_PARAM, VCF_FILE_IDS_FIELD));
    List<VcfFile> vcfFiles = vcfFileManager.loadVcfFiles(filterForm.getVcfFileIds());

    List<Chromosome> chromosomes = referenceGenomeManager.loadChromosomes(vcfFiles.get(0).getReferenceId());
    Map<Long, Chromosome> chromosomeMap = chromosomes.parallelStream()
            .collect(Collectors.toMap(BaseEntity::getId, chromosome -> chromosome));

    List<Long> chromosomeIds = featureIndexDao.getChromosomeIdsWhereVariationsPresentFacet(vcfFiles,
            filterForm.computeQuery(FeatureType.VARIATION));

    return chromosomeIds.stream().map(chromosomeMap::get).collect(Collectors.toList());
}

From source file:org.ligoj.app.plugin.prov.azure.in.ProvAzurePriceImportResource.java

/**
 * Install compute prices from the JSON file provided by Azure.
 *
 * @param context// ww  w . j  ava  2  s .c o m
 *            The update context.
 */
private void installComputePrices(final UpdateContext context) throws IOException {
    context.setInstanceTypes(itRepository.findAllBy(BY_NODE, context.getNode().getId()).stream()
            .collect(Collectors.toMap(ProvInstanceType::getName, Function.identity())));

    // Install Pay-as-you-Go, one year, three years
    installComputePrices(context, "base", 1);
    installComputePrices(context, "base-one-year", 12);
    installComputePrices(context, "base-three-year", 36);
    nextStep(context.getNode(), "flush", 1);
}

From source file:com.github.sevntu.checkstyle.ordering.MethodOrder.java

private static Map<String, Method> getAllMethods(Dependencies dependencies) {
    return dependencies.getMethods().stream()
            .collect(Collectors.toMap(MethodDefinition::getSignature, Method::new));
}

From source file:com.teradata.benchto.driver.loader.BenchmarkLoader.java

private Map<String, String> extractGlobalVariables(Map<String, Object> yaml) {
    return yaml.entrySet().stream().filter(entry -> !entry.getKey().equals(VARIABLES_KEY)).collect(Collectors
            .toMap(Entry::getKey, entry -> entry.getValue() == null ? null : entry.getValue().toString()));
}

From source file:com.streamsets.pipeline.lib.el.StringEL.java

@ElFunction(prefix = "map", name = "join", description = "Returns each element of a LIST field joined on the specified character sequence.")
public static String joinMap(@ElParam("map") Map<String, Field> map, @ElParam("separator") String separator,
        @ElParam("keyValueSeparator") String kvSeparator) {
    if (map == null) {
        return "";
    }//  www  .j  a v  a  2s.co m

    Map<String, String> mapOfStrings = map.entrySet().stream().collect(Collectors.toMap(Map.Entry::getKey,
            e -> e.getValue().getValue() == null ? "null" : e.getValue().getValueAsString()));
    Joiner joiner = Joiner.on(separator);

    return joiner.withKeyValueSeparator(kvSeparator).join(mapOfStrings);
}

From source file:ch.algotrader.service.ib.IBNativeReferenceDataServiceImpl.java

private void retrieveFutures(FutureFamily securityFamily, Set<ContractDetails> contractDetailsSet) {

    // get all current futures
    List<Future> allFutures = this.futureDao.findBySecurityFamily(securityFamily.getId());
    Map<String, Future> mapByConid = allFutures.stream().filter(e -> e.getConid() != null)
            .collect(Collectors.toMap(e -> e.getConid(), e -> e));
    Map<String, Future> mapBySymbol = allFutures.stream().collect(Collectors.toMap(e -> e.getSymbol(), e -> e));

    for (ContractDetails contractDetails : contractDetailsSet) {

        Contract contract = contractDetails.m_summary;
        String conid = String.valueOf(contract.m_conId);
        if (!mapByConid.containsKey(conid)) {

            LocalDate expiration = DATE_FORMAT.parse(contract.m_expiry, LocalDate::from);
            String contractMonthString = contractDetails.m_contractMonth;
            LocalDate contractMonth = parseYearMonth(contractMonthString);

            String symbol = FutureSymbol.getSymbol(securityFamily, contractMonth,
                    this.commonConfig.getFutureSymbolPattern());
            if (!mapBySymbol.containsKey(symbol)) {
                Future future = Future.Factory.newInstance();

                final String isin = FutureSymbol.getIsin(securityFamily, contractMonth);
                String ric = FutureSymbol.getRic(securityFamily, contractMonth);

                future.setSymbol(symbol);
                future.setIsin(isin);//w w  w  . j  a  v  a 2  s .  c  o m
                future.setRic(ric);
                future.setConid(conid);
                future.setExpiration(DateTimeLegacy.toLocalDate(expiration));
                future.setMonthYear(contractMonthString);
                future.setSecurityFamily(securityFamily);
                future.setUnderlying(securityFamily.getUnderlying());

                if (LOGGER.isDebugEnabled()) {
                    LOGGER.debug("Creating future based on IB definition: {} {}", contract.m_symbol,
                            contractDetails.m_contractMonth);
                }
                this.futureDao.save(future);
            }
        }
    }
}