Shopping List

import com.sun.source.tree.WhileLoopTree;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;
import java.util.stream.Collectors;

public class ShoppingList {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        List<String> productList = Arrays
                .stream(scanner.nextLine().split("!"))
                .collect(Collectors.toList());

        String inputLine = scanner.nextLine();

        while (!inputLine.equals("Go Shopping!")) {
            String[] commandArr = inputLine.split(" ");
            String command = commandArr[0];

            switch (command) {
                case "Urgent":
                    String itemToAdd = commandArr[1];

                    if (!productList.contains(itemToAdd)) {
                        productList.add(0, itemToAdd);
                    }
                    break;
                case "Unnecessary":
                    String itemToRemove = commandArr[1];

                    productList.remove(itemToRemove);
                    break;
                case "Correct":
                    String oldItem = commandArr[1];
                    String newItem = commandArr[2];

                    if (productList.contains(oldItem)) {
                   int index = productList.indexOf(oldItem);
                       productList.set(index, newItem);
                    }
                    break;
                case "Rearrange":
                    String itemToRearrange = commandArr[1];
                    if (productList.contains(itemToRearrange)) {
                      productList.remove(itemToRearrange);
                      productList.add(itemToRearrange);
                    }
                    break;
            }
            inputLine = scanner.nextLine();
        }
        System.out.println(String.join(", ", productList));
    }
}