Unicode 编码解码工具类

 /**
     * 字符串转 Unicode 编码（标准格式 \\uXXXX）
     */

  public static String stringToUnicode(String str) {
        if (str == null || str.isEmpty()) {
            return "";
        }
        
        StringBuilder unicode = new StringBuilder();
        for (int i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            // 对非ASCII字符进行编码
            if (ch > 127) {
                unicode.append("\\u").append(String.format("%04x", (int) ch).toUpperCase());
            } else {
                unicode.append(ch);
            }
        }
        return unicode.toString();
    }

    /**
     * Unicode 解码为字符串（标准格式 \\uXXXX）
     */
    public static String unicodeToString(String unicodeStr) {
        if (unicodeStr == null || unicodeStr.isEmpty()) {
            return "";
        }
        
        Pattern pattern = Pattern.compile("(\\\\u[0-9a-fA-F]{4})");
        Matcher matcher = pattern.matcher(unicodeStr);
        
        StringBuffer sb = new StringBuffer();
        while (matcher.find()) {
            String unicode = matcher.group(1);
            char ch = (char) Integer.parseInt(unicode.substring(2), 16);
            matcher.appendReplacement(sb, String.valueOf(ch));
        }
        matcher.appendTail(sb);
        
        return sb.toString();
    }