Array Homework

package com.company;

public class Main {

    public static void main(String[] args) {
    int[] arr = {4, 7, 5, 6, 2};
    printArr(arr);
    AdditionArr(arr, 2);
    System.out.println(greaterNum(arr));
    System.out.println(evenArr(arr));
    System.out.println (arrIndex(arr, 2));
    }

    public static int greaterNum(int[] arr){
        int maxNum = arr[0];
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] > maxNum)
                maxNum = arr[i];
        }
        return maxNum;
    }

    public static void printArr(int[] arr){
        System.out.print("{");
        for (int i = 0; i < arr.length; i++) {
            System.out.print(i == arr.length-1 ? arr[i] : arr[i] + ",");
        }
        System.out.println("}");
    }

    public static boolean evenArr(int[] arr){
        boolean isTrue = false;
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] % 2 == 0){
                isTrue = true;
            } else {
                return false;
            }
        }
        return isTrue;
    }

    public static void AdditionArr(int[] arr, int times){
        for (int i = 0; i < arr.length; i++) {
            arr[i] += times;
            System.out.print(arr[i] + " ");
        }
        System.out.println("");
    }

    public  static int arrIndex(int[] arr, int position){
        for (int i = 0; i < arr.length; i++) {
            if(position > arr.length)
                return -1;
        }
        return arr[position];
    }
}