java中正则表达式提取字符串中日期实现代码

public String run(String text) {
        String dateStr = text.replaceAll("r?n", " ");
        dateStr = dateStr.replaceAll("\s+", " ");       
       
        try {
           
            List matches = null;
            Pattern p = Pattern.compile("(\d{1,4}[-|\\/]\d{1,2}[-|\\/]\d{1,2} \d{1,2}:\d{1,2}:\d{1,2})", Pattern.CASE_INSENSITIVE|Pattern.MULTILINE);
            Matcher matcher = p.matcher(dateStr);
            if (matcher.find() && matcher.groupCount() >= 1) {
                matches = new ArrayList();
                for (int i = 1; i <= matcher.groupCount(); i++) {
                    String temp = matcher.group(i);
                    matches.add(temp);
                }
            } else {
                matches = Collections.EMPTY_LIST;
            }           
           
            if (matches.size() > 0) {
                return ((String) matches.get(0)).trim();
            } else {
                return "";
            }
           
        } catch (Exception e) {
            return "";
        }
    }