Example usage for java.util Map forEach

List of usage examples for java.util Map forEach

Introduction

In this page you can find the example usage for java.util Map forEach.

Prototype

default void forEach(BiConsumer<? super K, ? super V> action) 

Source Link

Document

Performs the given action for each entry in this map until all entries have been processed or the action throws an exception.

Usage

From source file:Main.java

public static void main(String[] args) throws Exception {
    List<Person> persons = Arrays.asList(new Person("Max", 18), new Person("Peter", 23),
            new Person("Pamela", 23), new Person("David", 12));

    Map<Integer, List<Person>> personsByAge = persons.stream().collect(Collectors.groupingBy(p -> p.age));

    personsByAge.forEach((age, p) -> System.out.format("age %s: %s\n", age, p));
}

From source file:Main.java

public static void main(String[] args) {
    Map<Integer, String> map = new HashMap<>();

    for (int i = 0; i < 10; i++) {
        map.putIfAbsent(i, "val" + i);
    }// w  ww . ja v a 2  s  . c om

    map.forEach((id, val) -> System.out.println(val));
}

From source file:Main.java

public static void main(String[] args) {
    Map<Integer, String> map = new HashMap<>();

    for (int i = 0; i < 10; i++) {
        map.putIfAbsent(i, "val" + i);
    }//w  w w .j  av a2  s.c  o m

    map.forEach((id, val) -> System.out.println(val));

    System.out.println(map.getOrDefault(42, "not found")); // not found
}

From source file:Main.java

public static void main(String[] args) {
    Map<Integer, String> map = new HashMap<>();

    for (int i = 0; i < 10; i++) {
        map.putIfAbsent(i, "val" + i);
    }//  w  w  w .j a  v a2  s  .com

    map.forEach((id, val) -> System.out.println(val));

    map.remove(3, "val3");
    System.out.println(map.get(3)); // val33

    map.remove(3, "val33");
    System.out.println(map.get(3)); // null
}

From source file:Main.java

public static void main(String[] args) {
    Map<Integer, String> map = new HashMap<>();

    for (int i = 0; i < 10; i++) {
        map.putIfAbsent(i, "val" + i);
    }/*from www .j  a v  a  2 s.  c om*/

    map.forEach((id, val) -> System.out.println(val));

    map.merge(9, "val9", (value, newValue) -> value.concat(newValue));
    System.out.println(map.get(9)); // val9

    map.merge(9, "concat", (value, newValue) -> value.concat(newValue));
    System.out.println(map.get(9)); // val9concat
}

From source file:Main.java

public static void main(String[] args) {
    Map<Integer, String> map = new HashMap<>();

    for (int i = 0; i < 10; i++) {
        map.putIfAbsent(i, "val" + i);
    }//  w w w  .ja  v  a  2s  .  c o m

    map.forEach((id, val) -> System.out.println(val));

    map.computeIfPresent(3, (num, val) -> val + num);
    System.out.println(map.get(3)); // val33

    map.computeIfPresent(9, (num, val) -> null);
    System.out.println(map.containsKey(9)); // false

    map.computeIfAbsent(23, num -> "val" + num);
    System.out.println(map.containsKey(23)); // true

    map.computeIfAbsent(3, num -> "bam");
    System.out.println(map.get(3)); // val33
}

From source file:com.ryft.spark.connector.examples.SimplePairRDDExampleJ.java

public static void main(String[] args) {
    final SparkConf sparkConf = new SparkConf().setAppName("SimplePairRDDExampleJ").setMaster("local[2]");

    final SparkContext sc = new SparkContext(sparkConf);
    final SparkContextJavaFunctions javaFunctions = RyftJavaUtil.javaFunctions(sc);
    final byte fuzziness = 0;
    final int surrounding = 10;
    final List queries = toScalaList(RyftQueryUtil.toSimpleQueries("Jones", "Thomas"));

    final RyftPairJavaRDD rdd = javaFunctions.ryftPairJavaRDD(queries,
            RyftQueryOptions.apply("passengers.txt", surrounding, fuzziness), RyftJavaUtil.ryftQueryToEmptyList,
            RyftJavaUtil.stringToEmptySet);

    final Map<String, Long> countByKey = rdd.countByKey();
    final StrBuilder sb = new StrBuilder();
    countByKey.forEach((key, value) -> sb.append(key + " -> " + value + "\n"));
    logger.info("RDD count by key: \n{}", sb.toString());
}

From source file:Main.java

public static void main(String[] args) {
    Map<String, String> map = new HashMap<>();
    map.put("CSS", "style");
    map.put("HTML", "mark up");
    map.put("Oracle", "database");
    map.put("XML", "data");

    map.forEach((String key, String value) -> {
        System.out.println("key=" + key + ",  value=" + value);
    });//  w w w. j  av  a 2  s  .co  m

}

From source file:pl.prutkowski.java.playground.java8.TestCollectors.java

/**
 * @param args the command line arguments
 *///from w  ww .ja va 2  s.  c  o  m
public static void main(String[] args) {
    Map<String, Integer> monthByLen = months.stream()
            .collect(Collectors.toMap(String::toUpperCase, m -> StringUtils.countMatches(m, "e")));

    monthByLen.forEach((month, eCount) -> System.out.println(month + " -> " + eCount));

    System.out.println("---------------------------------");

    Map<Object, List<String>> monthByLen2 = months.stream()
            .collect(Collectors.groupingBy(m -> StringUtils.countMatches(m, "e")));

    monthByLen2.forEach((count, groupedMonths) -> System.out.println(count + " -> " + groupedMonths));

    System.out.println("---------------------------------");

    Double averageLength = months.stream().collect(Collectors.averagingDouble(String::length));
    System.out.println("Average length: " + averageLength);
    System.out.println("---------------------------------");

    Double max = months.stream().collect(Collectors.summarizingDouble(String::length)).getMax();
    System.out.println("Max length: " + max);
    System.out.println("---------------------------------");

    String reduced = months.stream().collect(Collectors.reducing((m1, m2) -> (m1 + ", " + m2))).get();
    System.out.println("Reduced: " + reduced);
    System.out.println("---------------------------------");
    System.out.println(String.join(", ", months));
    System.out.println("---------------------------------");

    List<String> monthsWithZ = months.stream().filter(m -> m.contains("z")).collect(new ListCollector<>());
    System.out.println(monthsWithZ);

}

From source file:examples.cnn.ImagesClassification.java

public static void main(String[] args) {

    SparkConf conf = new SparkConf();
    conf.setAppName("Images CNN Classification");
    conf.setMaster(String.format("local[%d]", NUM_CORES));
    conf.set(SparkDl4jMultiLayer.AVERAGE_EACH_ITERATION, String.valueOf(true));

    try (JavaSparkContext sc = new JavaSparkContext(conf)) {

        JavaRDD<String> raw = sc.textFile("data/images-data-rgb.csv");
        String first = raw.first();

        JavaPairRDD<String, String> labelData = raw.filter(f -> f.equals(first) == false).mapToPair(r -> {
            String[] tab = r.split(";");
            return new Tuple2<>(tab[0], tab[1]);
        });/*from  w w  w.ja v  a2  s.c o  m*/

        Map<String, Long> labels = labelData.map(t -> t._1).distinct().zipWithIndex()
                .mapToPair(t -> new Tuple2<>(t._1, t._2)).collectAsMap();

        log.info("Number of labels {}", labels.size());
        labels.forEach((a, b) -> log.info("{}: {}", a, b));

        NetworkTrainer trainer = new NetworkTrainer.Builder().model(ModelLibrary.net1)
                .networkToSparkNetwork(net -> new SparkDl4jMultiLayer(sc, net)).numLabels(labels.size())
                .cores(NUM_CORES).build();

        JavaRDD<Tuple2<INDArray, double[]>> labelsWithData = labelData.map(t -> {
            INDArray label = FeatureUtil.toOutcomeVector(labels.get(t._1).intValue(), labels.size());
            double[] arr = Arrays.stream(t._2.split(" ")).map(normalize1).mapToDouble(Double::doubleValue)
                    .toArray();
            return new Tuple2<>(label, arr);
        });

        JavaRDD<Tuple2<INDArray, double[]>>[] splited = labelsWithData.randomSplit(new double[] { .8, .2 },
                seed);

        JavaRDD<DataSet> testDataset = splited[1].map(t -> {
            INDArray features = Nd4j.create(t._2, new int[] { 1, t._2.length });
            return new DataSet(features, t._1);
        }).cache();
        log.info("Number of test images {}", testDataset.count());

        JavaRDD<DataSet> plain = splited[0].map(t -> {
            INDArray features = Nd4j.create(t._2, new int[] { 1, t._2.length });
            return new DataSet(features, t._1);
        });

        /*
         * JavaRDD<DataSet> flipped = splited[0].randomSplit(new double[] { .5, .5 }, seed)[0].
         */
        JavaRDD<DataSet> flipped = splited[0].map(t -> {
            double[] arr = t._2;
            int idx = 0;
            double[] farr = new double[arr.length];
            for (int i = 0; i < arr.length; i += trainer.width) {
                double[] temp = Arrays.copyOfRange(arr, i, i + trainer.width);
                ArrayUtils.reverse(temp);
                for (int j = 0; j < trainer.height; ++j) {
                    farr[idx++] = temp[j];
                }
            }
            INDArray features = Nd4j.create(farr, new int[] { 1, farr.length });
            return new DataSet(features, t._1);
        });

        JavaRDD<DataSet> trainDataset = plain.union(flipped).cache();
        log.info("Number of train images {}", trainDataset.count());

        trainer.train(trainDataset, testDataset);
    }
}