My objective is to remove all negative numbers from an array in Java.

I have written the below code. How do I improve the complexity of code or is there a good algorithm?

```
public static void main(String[] args) {
    int[] array = { 1, -3, 4, -9, 3, 4, 70, -10, 0, 7 };
    System.out.println(Arrays.toString(removeNegativeNumbers(array)));
}

public static int[] removeNegativeNumbers(int[] num) {
    List<Integer> list = new ArrayList<>();
    for (int n : num) {
        if (n >= 0) {
            list.add(n);
        }
    }
    int[] result = new int[list.size()];
    for (int i = 0; i < result.length; i++) {
        result[i] = list.get(i).intValue();
    }
    return result;
}

```