get last index of array java

firstNum = numbers[0];
lastNum = numbers[numbers.length-1];

int[] someArray = {1,2,3,4,5};
int first = someArray[0];
int last = someArray[someArray.length - 1];
System.out.println("First: " + first + "\n" + "Last: " + last);

firstNum = numbers.get(0);
lastNum = numbers.get(numbers.size() - 1);