Java 8 将 int[][] 转换为 Integer[][] 的方法

Question

How to convert java int[][] to Integer[][] ? .It seems easy to convert single dimensional primitive array to Object type single dimensional array using java stream.

For example

Integer[] result = IntStream.of( intarray ).boxed().toArray( Integer[]::new );

Is there any way for two dimensional array like above ?

Answer 1

You can do the same thing within a map operation

int[][] twoDimenArray = {};
Integer[][] result = Stream.of(twoDimenArray)
    .map(array -> IntStream.of(array).boxed().toArray(Integer[]::new))
    .toArray(Integer[][]::new);

Answer 2

You can use Arrays.stream method:

int[][] arr1 = {};

Integer[][] arr2 = Arrays.stream(arr1)
        .map(row -> Arrays.stream(row)
                .boxed()
                .toArray(Integer[]::new))
        .toArray(Integer[][]::new);