如何通过指定几个字符而不是整个字符串来获取java列表的索引？

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

public class Main {
    public static void main(String[] args) {
        List<String> list = new ArrayList<>();
        list.add("apple");
        list.add("banana");
        list.add("cherry");

        String searchChar = "b";
        int index = -1;

        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).indexOf(searchChar) != -1) {
                index = i;
                break;
            }
        }

        System.out.println("Index of '" + searchChar + "' in the list: " + index);
    }
}