Collecting Results Collector Methods

Question 1

Collector.averagingDouble() return type?

Answer 1

Double

Question 2

Collector.counting() return type?

Answer 2

Long

Question 3

Collector.groupingBy(Function f) return type?

Answer 3

Map

Question 4

Collector.joining(CharacterSequence cs ) return type?

Answer 4

String

Question 5

Collector.maxBy(Comparator c) or Collector.minBy(Comparator c) return type?

Answer 5

Optional

Question 6

Collector.mapping(Function f, Collector dc) return type?

Answer 6

Collector

Question 7

Collector.partitioningBy(Predicate p) or Collector.partitioningBy(Predicate p, Collector dc) return type?

Answer 7

Map

Question 8

Collector.summarizingDouble(ToDoubleFunction) return type?

Answer 8

DoubleSummaryStatistic

Question 9

Collector.summarizingInt(toIntFunction) return type?

Answer 9

IntSummaryStatistics

Question 10

Collector.summarizingLong(ToLongFunction) return type?

Answer 10

LongSummaryStatistics

Question 11

Collector.toList() or Collector.toSet() return type?

Answer 11

List or Set

Question 12

Collector.toCollection(Supplier s) return type?

Answer 12

Collection

Question 13

Collector.toMap(Function k, Function v),

Collector.toMap(Function k, Function v, BinaryOperator m) return type?

Answer 13

Map