EN
Java - create list from array
8
points
In java we have couple of ways to convert array to list.
1. Using Arrays.asList
String[] arr = {"Tim", "Jerry", "Ann"};
List<String> list = Arrays.asList(arr);
// [Tim, Jerry, Ann]
System.out.println(list.toString());
2. Using ArrayList constructor
String[] arr = {"Tim", "Jerry", "Ann"};
List<String> list = new ArrayList<>(Arrays.asList(arr));
// [Tim, Jerry, Ann]
System.out.println(list.toString());
3. Array with primitive type
int[] arr = {1, 2, 3};
List<Integer> list = Arrays.stream(arr).boxed().collect(Collectors.toList());
// [1, 2, 3]
System.out.println(list.toString());
4. Using Guava
String[] arr = {"Tim", "Jerry", "Ann"};
List<String> list = Lists.newArrayList(arr);
// [Tim, Jerry, Ann]
System.out.println(list.toString());
5. Using Apache Commons Collections
String[] arr = {"Tim", "Jerry", "Ann"};
List<String> list = new ArrayList<>();
CollectionUtils.addAll(list, arr);
// [Tim, Jerry, Ann]
System.out.println(list.toString());
6. Write own converter with java generic
// generic method
public static <T> List<T> createListFromArray(T array[]) {
List<T> list = new ArrayList<>();
for (T t : array) {
list.add(t);
}
return list;
}
String[] arr = {"Tim", "Jerry", "Ann"};
List<String> list = createListFromArray(arr);
// [Tim, Jerry, Ann]
System.out.println(list.toString());