Java List to Array...

Question

how to convert a Integer list into a integer array ?

Answer 1

if the result is primitive int[] use for() loop

ArrayList<Integer> aList = new ArrayList<>(List.of(0,1,2,3,4,5) );
int[] ai = new int[aList.size() ];

int i=0;
for(Integer e : aList) ai[i++] = e;

System.out.println(Arrays.toString(ai) );

or if result is Integer[]
Integer[] aI = new Integer[aList.size() ];
aList.toArray(aI);
or
Integer[] aI = aList.toArray(new Integer[0] );