-
Notifications
You must be signed in to change notification settings - Fork 0
/
LIstToArrTest.java
32 lines (25 loc) · 1.04 KB
/
LIstToArrTest.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
package lang;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
public class LIstToArrTest {
public static void main(String[] args) {
List<Integer> list = new ArrayList<>();
list.add(1);
list.add(2);
list.add(3);
//List<Integer> --> int[]
int[] ints = list.stream().mapToInt(Integer::intValue).toArray();
//List<Integer> --> Integer[]
Integer[] integersArr = list.toArray(new Integer[list.size()]);
//int[]--> Integer[]
Integer[] integersArr1 = Arrays.stream(ints).boxed().toArray(Integer[]::new);
//Integer[] --> int[]
int[] ints1 = Arrays.stream(integersArr).mapToInt(Integer::intValue).toArray();
System.out.println("ints = " + Arrays.toString(ints));
System.out.println("integersArr = " + Arrays.toString(integersArr));
System.out.println("integersArr1 = " + Arrays.toString(integersArr1));
System.out.println("ints1 = " + Arrays.toString(ints1));
}
}