StreamsAPI-Tutorials/StreamExamples/RemoveDuplicates.java at main · CodeJamm/StreamsAPI-Tutorials · GitHub

36 lines (28 loc) · 1.19 KB

package StreamExamples;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.Map;

import java.util.Set;

import java.util.function.Function;

import java.util.stream.Collectors;

public class RemoveDuplicates

{

public static void main(String[] args)

{

//using stream.distinct()

List<Integer> numbersList1 = new ArrayList<>(Arrays.asList(1, 1, 2, 3, 3, 3, 4, 5, 6, 6, 6, 7, 8));

List<Integer> listWithoutDuplicates = numbersList1.stream()

.distinct().collect(Collectors.toList());

System.out.println(listWithoutDuplicates);

// using stream.toSet()

List<Integer> numbersList2 = new ArrayList<>(Arrays.asList(1, 1, 2, 3, 3, 3, 4, 5, 6, 6, 6, 7, 8));

Set<Integer> setWithoutDuplicates = numbersList2.stream().collect(Collectors.toSet());

System.out.println(setWithoutDuplicates);

//using stream.toMap()

List<Integer> numbersList3 = new ArrayList<>(Arrays.asList(1, 1, 2, 3, 3, 3, 4, 5, 6, 6, 6, 7, 8));

Map<Integer, Long> elementCountMap = numbersList3.stream()

.collect(Collectors.toMap(Function.identity(), v -> 1L, Long::sum));

System.out.println(elementCountMap);

}

Expand file tree