中文或中文字符识别

/**
 * 截取指定长度的字符串（中文或中文标点占两位，其他一位）
 * @param str
 * @param len
 * @return
 */
public static String substrOfLength(String str, int len) {
    String result = null;
    if (str == null || str.equals("")) {
        result = "";
    } else {
        StringBuilder sb = new StringBuilder();
        int strLen = 0;
        for (char c : str.toCharArray()) {
            //中文的编码区间来判断是否中文
            if ((c >= 0x4E00 && c <= 0x9FA5) || isChinese(c)) {
                strLen += 2;
            }else{
                strLen += 1;
            }
            if(strLen <= len){
                sb.append(c);
            }else{
                break;
            }
        }
        result = sb.toString();
    }
    return result;
}

/**
 * 使用Unicode编码来判断中文标点
 * @param c
 * @return
 */
public static boolean isChinese(char c) {
    Character.UnicodeBlock ub = Character.UnicodeBlock.of(c);
    if (ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS
            || ub == Character.UnicodeBlock.CJK_COMPATIBILITY_IDEOGRAPHS
            || ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS_EXTENSION_A
            || ub == Character.UnicodeBlock.GENERAL_PUNCTUATION
            || ub == Character.UnicodeBlock.CJK_SYMBOLS_AND_PUNCTUATION
            || ub == Character.UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS) {
        return true;
    }
    return false;
}