正则表达式 string.replaceAll替换花括号 报错illegal repetition near index 0

String regex = "(\\$|\\#)\\{[^{}]*\\}";//匹配的是#{xxx}或者${xxx}
List<WatcherTaskAgentFileMapping> watcherTaskAgentFileMappingList = agentFileQueryDao.queryWatcherAgentFileList(taskId);
Map<String, String> paramMap = new HashMap<>();
for (WatcherTaskAgentFileMapping watcherTaskAgentFileMapping : watcherTaskAgentFileMappingList) {
    Integer count = 1;
    String fileUrl = watcherTaskAgentFileMapping.getFileUrl();
    Pattern p = Pattern.compile(regex);
    Matcher matcher = p.matcher(fileUrl);
    while (matcher.find()) {
        String searchStr = fileUrl.substring(matcher.start(), matcher.end());
        if (StringUtils.isEmpty(paramMap.get(searchStr))) {
            paramMap.put(searchStr, "${参数" + count++ + "}");
        }
    }
}
if (!CollectionUtils.isEmpty(paramMap)) {
    String regexAll = "(\\$|\\#)\\{[^{参数}]*\\}";//匹配除$/#{参数x} 外的 $/#{xxx}
    Pattern p = Pattern.compile(regexAll);
    for (WatcherTaskAgentFileMapping watcherTaskAgentFileMapping : watcherTaskAgentFileMappingList) {
        for (String paramKey : paramMap.keySet()) {
            String fileUrl = watcherTaskAgentFileMapping.getFileUrl();
            while (p.matcher(fileUrl).find()) {//因为string.replaceAll(a,b) a 参数，可以单独替换‘{’或者‘}’，如果是字符串{xxx},会报错，但是replace就不会
                fileUrl = watcherTaskAgentFileMapping.getFileUrl().replace(paramKey, paramMap.get(paramKey));
            }
            watcherTaskAgentFileMapping.setFileUrl(fileUrl);
        }
    }
}

 replaceAll 替换带有花括号的字符串会报错，单独替换前花括号或者后花括号加上转义符不会报错；例如 "{cesi".replaceAll("\\{","a") = acesi

 replace 替换带有花括号的字符串不会报错