code: public static String getPropNameForAccessor(String accessorName) {
          if (!isValidAccessorName(accessorName)) return accessorName;
          int prefixLength = accessorName.startsWith("is") ? 2 : 3;
          return String.valueOf(accessorName.charAt(prefixLength)).toLowerCase() + accessorName.substring(prefixLength + 1);
      }
docs: Returns the property name, e.g. age, given an accessor name, e.g. getAge.
  Returns the original if a valid prefix cannot be removed.
  
  @param accessorName the accessor name of interest, e.g. getAge
  @return the property name, e.g. age, or original if not a valid property accessor name