How to convert long[] to List in Java?

Approach 1: By traversing to the elements of array

public static List<Long> getBoxedList_approach1(long[] arr) {
 if (arr == null)
  return null;

 List<Long> result = new ArrayList<>();

 for (long i : arr) {
  result.add(i);

 }
 return result;
}

Approach 2: Using LongStream

public static List<Long> getBoxedList_approach2(long[] arr) {
 if (arr == null)
  return null;

 List<Long> result = LongStream.of(arr).boxed().collect(Collectors.toList());
 return result;
}

Approach 3: Using Arrays.stream

public static List<Long> getBoxedList_approach3(long[] arr) {
 if (arr == null)
  return null;

 List<Long> result = Arrays.stream(arr).boxed().collect(Collectors.toList());
 return result;
}

App.java

package com.sample.app;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.LongStream;

public class App {

 private static void printElements(List<Long> arr) {
  for (long i : arr) {
   System.out.print(i + " ");
  }
  System.out.println();
 }

 public static List<Long> getBoxedList_approach1(long[] arr) {
  if (arr == null)
   return null;

  List<Long> result = new ArrayList<>();

  for (long i : arr) {
   result.add(i);

  }
  return result;
 }

 public static List<Long> getBoxedList_approach2(long[] arr) {
  if (arr == null)
   return null;

  List<Long> result = LongStream.of(arr).boxed().collect(Collectors.toList());
  return result;
 }

 public static List<Long> getBoxedList_approach3(long[] arr) {
  if (arr == null)
   return null;

  List<Long> result = Arrays.stream(arr).boxed().collect(Collectors.toList());
  return result;
 }

 public static void main(String args[]) throws IOException {
  long[] arr = { 1, 3, 5, 7, 2, 4, 6, 8, 10 };

  List<Long> result1 = getBoxedList_approach1(arr);
  printElements(result1);

  List<Long> result2 = getBoxedList_approach2(arr);
  printElements(result2);

  List<Long> result3 = getBoxedList_approach3(arr);
  printElements(result3);

 }
}

Output

1 3 5 7 2 4 6 8 10

1 3 5 7 2 4 6 8 10

1 3 5 7 2 4 6 8 10

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