String 替换 {}里面的内容 正则表达式

    private static String replacePlaceholders(String input, Map<String, Object> placeholders) {
        StringBuffer output = new StringBuffer();


        Pattern pattern = Pattern.compile("\\{(.+?)\\}");
        Matcher matcher = pattern.matcher(input);

        while (matcher.find()) {
            String key = matcher.group(1);
            String replacement = placeholders.getOrDefault(key, "").toString();
            if (!replacement.equals("")) {
                matcher.appendReplacement(output, replacement);
            }

        }

        matcher.appendTail(output);


        return output.toString();
    }