How do I convert an array of strings into append-able list?

I have parsed through a CSV file and stored it as an array of strings. I'd like to add an item to each sub-array if certain conditions have been met, as shown below. However, I am not able to use the .add() method and get a "Cannot resolve method" message in my IDE. To try to get around this, I attempted to create a new arraylist in which I placed the contents of the string array, but the problem persisted. How do I make it so that I can add an item to each sublist?

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import java.util.List;
import java.util.ArrayList;


public class Application {
    /**
     * Main entry of the application.
     *
     * @param args This should be empty
     */
    public static void main(final String[] args) {
        String csvFile = "/IUCNListV2.csv";
        List<String[]> listAnimal =
        ReadCSV.readFileAndParseSkipFirstline(Application.class.getResourceAsStream(csvFile));


        List<String[]> list2 = new ArrayList<>();
        for (String [] text : listAnimal) {
            list2.add(text);
        }
        
        for(String[] subList: list2)
            if (null != subList && subList[4].equals("x") &&
                    subList[5].equals("y")) {
                subList.add("z");
            }
    }
}

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To convert an array of String to ArrayList simply use this

String[] x = {"example1","example2"};
ArrayList<String> list = new ArrayList<>(Arrays.asList(x));

You can't use the add method on arrays, because the add method is in the List interface, but you can use List<String> objects in your other list like this, for this solution:

public class Application {
    /**
     * Main entry of the application.
     *
     * @param args This should be empty
     */
    public static void main(final String[] args) {
        String csvFile = "/IUCNListV2.csv";
        List<List<String>> listAnimal =
                ReadCSV.readFileAndParseSkipFirstline(Application.class.getResourceAsStream(csvFile));


        List<List<String>> list2 = new ArrayList<>();
        list2.addAll(listAnimal);

        for(List<String> subList: list2)
            if (null != subList && subList.get(4).equals("x") &&
                    subList.get(5).equals("y")) {
                subList.add("z");
            }
    }
}

You can't add element in string array directly. You can follow those steps

• You can create list from string array
• Add the element in list
• Again convert list to array
• Update the outer list

for (int i = 0; i < list2.size(); i++) {
    String[] subList = list2.get(i);
    if (null != subList && subList[4].equals("x") &&
                    subList[5].equals("y")) {
        ArrayList<String> list = new ArrayList<>(Arrays.asList(subList)); // create a list
        list.add("z"); // add in list
        list2.set(i, list.toArray(new String[0])) // create array from list and update parent list
    }
}

Or create a List<List<String>> from List<String[]> first then add in inner list