Use Java please

1. Permutation (About ArrayList/Array, 40 points) Write two different methods, one uses recursion while the other uses iteration, to implement the following task: Get a list of integers from user, return all possible permutations. You could ask for size of the list first or you could use a flag to denote end of the list For example, suppose we get number 1, 2, 3 from user, then we have the following [1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], and [3,2,1]