/**

     * 首字母小写

     *

     * @param str

     * @return

     */

    public static String toLowerCaseFirstChar(String s) {

        if (Character.isLowerCase(s.charAt(0)))

            return s;

        else

            return (new StringBuilder())

                    .append(Character.toLowerCase(s.charAt(0)))

                    .append(s.substring(1)).toString();

    }

    /**

     * 首字母大写

     *

     * @param str

     * @return

     */

    public static String toUpperCaseFirstChar(String s) {

        if (Character.isUpperCase(s.charAt(0)))

            return s;

        else

            return (new StringBuilder())

                    .append(Character.toUpperCase(s.charAt(0)))

                    .append(s.substring(1)).toString();

    }