please post you're code and explain how you got you're answer. Must be done in java

This assignment presents multiple problems that must be solved recursively. While some problems might be solved easily with iteration the goal is to get a sense of solving problems recursively. Each problem has an accompanying class file that contains tests to validate your solution as well as the method or methods to implement for each problem. You may implement any additional helper methods to help you solve the problem so long as iteration is not used except where specified. You may not change the initial method header. Problem 4 - Reverse Array (15 points) Reverse order for this problem means from N to 0 where N is the last index of the array. So, if an array has a last index of 3 then reverse order would be 3,2,1,0