GalaxyOverMe/Java-Grammar

String [] → List<String>

String[] array = {"1", "2", "3"};
List<String> list = Arrays.asList(array);

List<String> → String []

List<String> list = Arrays.asList("1", "2", "3");
String[] array = list.toArray(new String[0]);

int [] → List<Integer>

int[] array = {1, 2, 3};
List<Integer> list = Arrays.stream(array).boxed().toList();

List<Integer> → int []

List<Integer> list = new ArrayList(Arrays.asList(1, 2, 3));
int[] array = list.stream().mapToInt(i -> i).toArray();

int [] → Integer []

int[] intArray = {1, 2, 3};
Integer[] IntArray = Arrays.stream(intArray).boxed().toArray(Integer[]::new);

Integer [] → int []

Integer[] IntArray = {1, 2, 3};
int[] intArray = Arrays.stream(IntArray).mapToInt(i -> i).toArray();