variables - How does pointing to objects work in java?

Because Java Array is considered Reference Object.

int[] b = a;    // variable 'b' points same memory location with 'a'

If you want to copy all value of a, write code below

@Test
public void arrayCopy1() {
    int[] a = {1, 2, 3};
    int[] b = a;
    System.out.println(a); //Point [I@64a294a6
    System.out.println(b); //Point [I@64a294a6
    printArrayValues(a);   //[1,2,3]
    printArrayValues(b);   //[1,2,3]
    a[0] = 10;
    printArrayValues(a);   //[10,2,3]
    printArrayValues(b);   //[10,2,3]
}
@Test
public void arrayCopy2() {
    int[] a = {1, 2, 3};
    int[] b = Arrays.copyOf(a, a.length);
    System.out.println(a); //Point [I@64a294a6
    System.out.println(b); //Point [I@7e0b37bc
    printArrayValues(a);   //[1,2,3]
    printArrayValues(b);   //[1,2,3]
    a[0] = 10;
    printArrayValues(a);   //[10,2,3]
    printArrayValues(b);   //[1,2,3]
}
private void printArrayValues(int[] arr) {
    System.out.print("[");
    for(int i = 0 ; i < arr.length ; i++) {
        System.out.print(arr[i]);
        if (i != arr.length-1)
            System.out.print(",");
    }
    System.out.println("]");
}