jetbrick-commons/src/main/java/jetbrick/lang/StringUtils.java
public static int lastIndexOfIgnoreCase(String s, char c, int startIndex, int endIndex) {
        int total = s.length() - 1;
        if (total < 0) {
            return -1;
        }
        if (startIndex >= total) {
            startIndex = total;
        }
        if (endIndex < 0) {
            endIndex = 0;
        }
        c = Character.toLowerCase(c);
        for (int i = startIndex; i >= endIndex; i--) {
            if (Character.toLowerCase(s.charAt(i)) == c) {
                return i;
            }
        }
        return -1;
    }
public static int lastIndexOfIgnoreCase(String s, char c, int startIndex, int endIndex) {
        int total = s.length() - 1;
        if (total < 0) {
            return -1;
        }
        if (startIndex >= total) {
            startIndex = total;
        }
        if (endIndex < 0) {
            endIndex = 0;
        }
        c = Character.toLowerCase(c);
        for (int i = startIndex; i >= endIndex; i--) {
            if (Character.toLowerCase(s.charAt(i)) == c) {
                return i;
            }
        }
        return -1;
    }
Finds last index of a character in the given source string in specified range [end, start]