JF-ExcMethods11.Array Manipulator

import java.util.Scanner;

public class Exc11ArrayManipulator {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String[] data = scanner.nextLine().split(" ");
        int[] array = new int[data.length];
        for (int i = 0; i < data.length; i++) {
            array[i] = Integer.parseInt(data[i]);
        }
        String input = scanner.nextLine();
        while (!"end".equals(input)) {
            String[] tokens = input.split(" ");
            String command = tokens[0];
            switch (command) {
                case "exchange": {
                    int index = Integer.parseInt(tokens[1]);
                    if (index < 0 || index >= array.length) {
                        System.out.println("Invalid index");
                    } else {
                        exchange(array, index);
                    }
                }
                break;
                case "min": {
                    String evenOrOdd = tokens[1];
                    if (evenOrOdd.equals("even")) {
                        findMinEven(array);
                    } else if (evenOrOdd.equals("odd")) {
                        findMinOdd(array);
                    }
                }
                break;
                case "max": {
                    String evenOrOdd = tokens[1];
                    if (evenOrOdd.equals("even")) {
                         findMaxEven(array);
                    } else if (evenOrOdd.equals("odd")) {
                        findMaxOdd(array);
                    }
                }
                break;
                case "first": {
                    int count = Integer.parseInt(tokens[1]);
                    if (count > array.length){
                        System.out.println("Invalid count");
                    }else{
                        String evenOrOdd = tokens[2];
                        if (evenOrOdd.equals("even")) {
                            findFirstEvenCount(array,count);
                        } else if (evenOrOdd.equals("odd")) {
                            findFirstOddCount(array,count );
                        }
                    }
                }
                break;
                case "last": {
                    int count = Integer.parseInt(tokens[1]);
                    if (count > array.length){
                        System.out.println("Invalid count");
                    }else {
                        String evenOrOdd = tokens[2];
                        if (evenOrOdd.equals("even")) {
                            findLastEvenCount(array, count);
                        } else if (evenOrOdd.equals("odd")) {
                            findLastOddCount(array, count);
                        }
                    }
                }
                break;
            }
            input = scanner.nextLine();
        }
        printArray(array);
    }

    private static void findLastOddCount(int[] array, int count) {
        int[] result = new int[0];
        for (int i = array.length -1; i >= 0 ; i--) {
            if (array[i] % 2 != 0){
                result = expandAndAddToArrResult(result,array[i]);
                if (result.length == count){
                    break;
                }
            }
        }
        reverseArray(result);
        printArray(result);
    }

    private static void findLastEvenCount(int[] array, int count) {
        int[] result = new int[0];
        for (int i = array.length -1; i >= 0 ; i--) {
            if (array[i] % 2==0){
                result = expandAndAddToArrResult(result,array[i]);
                if (result.length == count){
                    break;
                }
            }
        }
        reverseArray(result);
        printArray(result);
    }

    private static void reverseArray(int[] array) {
        int[] temp = copyArray(array);
        for (int i = array.length - 1; i >= 0 ; i--) {
            array[i] = temp[array.length-1 - i];
        }
    }

    private static void findFirstOddCount(int[] array, int count) {
        int[] result = new int[0];
        for (int i = 0; i < array.length ; i++) {
            if (array[i] % 2 != 0){
                result = expandAndAddToArrResult(result,array[i]);
                if (result.length == count){
                    break;
                }
            }
        }
        printArray(result);
    }

    private static void findFirstEvenCount(int[] array, int count) {
        int[] result = new int[0];
        for (int i = 0; i < array.length ; i++) {
            if (array[i] % 2 == 0){
               result = expandAndAddToArrResult(result,array[i]);
                if (result.length == count){
                    break;
                }
            }
        }
        printArray(result);
    }

    private static void printArray(int[] array) {
        System.out.print("[");
        for (int i = 0; i < array.length; i++) {
            if(i == 0) {
                System.out.print(array[i]);
            }else{
                System.out.print(", " + array[i]);
            }
        }
        System.out.println("]");
    }

    private static int[] expandAndAddToArrResult(int[] oldArray, int newElement) {
        int[] newArray = new int[oldArray.length + 1];
        for (int i = 0; i < oldArray.length; i++) {
            newArray[i]= oldArray[i];
        }
        newArray[newArray.length - 1] = newElement;
        return newArray;
    }

    private static void findMaxOdd(int[] array) {
        int max = Integer.MIN_VALUE;
        int index = -1;
        for (int i = 0; i < array.length; i++) {
            if (array[i] % 2 != 0 && max <= array[i]) {
                max = array[i];
                index = i;
            }
        }
        if (index == -1) {
            System.out.println("No matches");
        } else {
            System.out.println(index);
        }
    }

    private static void findMaxEven(int[] array) {
        int max = Integer.MIN_VALUE;
        int index = -1;
        for (int i = 0; i < array.length; i++) {
            if (array[i] % 2 == 0 && max <= array[i]) {
                max = array[i];
                index = i;
            }
        }
        if (index == -1) {
            System.out.println("No matches");
        } else {
            System.out.println(index);
        }
    }

    private static void findMinOdd(int[] array) {
        int min = Integer.MAX_VALUE;
        int index = -1;
        for (int i = 0; i < array.length; i++) {
            if (array[i] % 2 != 0 && min >= array[i]) {
                min = array[i];
                index = i;
            }
        }
        if (index == -1) {
            System.out.println("No matches");
        } else {
            System.out.println(index);
        }
    }

    private static void findMinEven(int[] array) {
        int min = Integer.MAX_VALUE;
        int index = -1;
        for (int i = 0; i < array.length; i++) {
            if (array[i] % 2 == 0 && min >= array[i]) {
                min = array[i];
                index = i;
            }
        }
        if (index == -1) {
            System.out.println("No matches");
        } else {
            System.out.println(index);
        }
    }

    private static void exchange(int[] array, int index) {
        int[] temp = copyArray(array);
        int count = 0;
        for (int i = index + 1; i < temp.length; i++) {
            array[count] = temp[i];
            count++;
        }
        for (int i = 0; i <= index; i++) {
            array[count] = temp[i];
            count++;
        }
    }

    private static int[] copyArray(int[] arr) {
        int[] newArray = new int[arr.length];
        for (int i = 0; i < arr.length; i++) {
            newArray[i] = arr[i];
        }
        return newArray;
    }
}