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/**     * 
Checks if a CharSequence is empty (""), null or whitespace only.
     *     * 
Whitespace is defined by {@link Character#isWhitespace(char)}.
     *     * 
     * StringUtils.isBlank(null)      = true     * StringUtils.isBlank("")        = true     * StringUtils.isBlank(" ")       = true     * StringUtils.isBlank("bob")     = false     * StringUtils.isBlank("  bob  ") = false     * 
     *     * @param cs  the CharSequence to check, may be null     * @return {@code true} if the CharSequence is null, empty or whitespace only     * @since 2.0     * @since 3.0 Changed signature from isBlank(String) to isBlank(CharSequence)     */public static boolean isBlank(final CharSequence cs) {
            int strLen;        if (cs == null || (strLen = cs.length()) == 0) {
                return true;        }        for (int i = 0; i < strLen; i++) {
                if (!Character.isWhitespace(cs.charAt(i))) {
                    return false;            }        }        return true;    }    /**     * 
Checks if a CharSequence is not empty (""), not null and not whitespace only.
     *     * 
Whitespace is defined by {@link Character#isWhitespace(char)}.
     *     * 
     * StringUtils.isNotBlank(null)      = false     * StringUtils.isNotBlank("")        = false     * StringUtils.isNotBlank(" ")       = false     * StringUtils.isNotBlank("bob")     = true     * StringUtils.isNotBlank("  bob  ") = true     * 
     *     * @param cs  the CharSequence to check, may be null     * @return {@code true} if the CharSequence is     *  not empty and not null and not whitespace only     * @since 2.0     * @since 3.0 Changed signature from isNotBlank(String) to isNotBlank(CharSequence)     */    public static boolean isNotBlank(final CharSequence cs) {
            return !isBlank(cs);    }

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