The for csv cell value is ABCDEFGHIJK Read csv file like "A","BCD", "EFGH","IJK" based on the character value like - [1,2,5,9]

import com.opencsv.CSVReader;
import java.io.FileReader;
import java.util.Arrays;
import java.util.List;

public class Main {
    public static void main(String[] args) throws Exception {
        // Define the indices to extract
        List<Integer> indices = Arrays.asList(1, 2, 5, 9);

        // Create a CSVReader
        CSVReader reader = new CSVReader(new FileReader("yourfile.csv"));

        // Read the CSV file
        String[] nextLine;
        while ((nextLine = reader.readNext()) != null) {
            // For each line, concatenate the cell values into a single string
            StringBuilder cellValues = new StringBuilder();
            for (String cell : nextLine) {
                cellValues.append(cell);
            }

            // Extract the characters at the specified indices
            for (int index : indices) {
                if (index < cellValues.length()) {
                    System.out.println("Character at index " + index + ": " + cellValues.charAt(index));
                }
            }
        }

        reader.close();
    }
}