String replaceLast

StringExample

public String replaceAtLast(String source,final String matchChar char,final String replaceChar){
    StringBuilder b = new StringBuilder(source);
    b.replace(source.lastIndexOf(char), source.lastIndexOf(char) + 1, replaceChar );
    source = b.toString();
}

public String trimLast(String source ,final String matchChar) {
    if (source.length() > 0 && source.charAt(str.length()-1) == matchChar) {
      source = source.substring(0, source.length()-1);
    }
    return source;
}