java正则实现各种日期格式化

packagecom.st.test;

 

importjava.text.DateFormat;

importjava.text.SimpleDateFormat;

importjava.util.Date;

importjava.util.HashMap;

importjava.util.regex.Pattern;

 

publicclass DateFormatUtil {

     

    @SuppressWarnings("finally")

    publicstatic String FormatDate(String dateStr){

 

        HashMap<String, String> dateRegFormat = newHashMap<String, String>();

        dateRegFormat.put(

                "^\\d{4}\\D+\\d{1,2}\\D+\\d{1,2}\\D+\\d{1,2}\\D+\\d{1,2}\\D+\\d{1,2}\\D*$",

                "yyyy-MM-dd-HH-mm-ss");//2014年3月12日 13时5分34秒，2014-03-12 12:05:34，2014/3/12 12:5:34

        dateRegFormat.put("^\\d{4}\\D+\\d{2}\\D+\\d{2}\\D+\\d{2}\\D+\\d{2}$",

                "yyyy-MM-dd-HH-mm");//2014-03-12 12:05

        dateRegFormat.put("^\\d{4}\\D+\\d{2}\\D+\\d{2}\\D+\\d{2}$",

                "yyyy-MM-dd-HH");//2014-03-12 12

        dateRegFormat.put("^\\d{4}\\D+\\d{2}\\D+\\d{2}$","yyyy-MM-dd");//2014-03-12

        dateRegFormat.put("^\\d{4}\\D+\\d{2}$","yyyy-MM");//2014-03

        dateRegFormat.put("^\\d{4}$","yyyy");//2014

        dateRegFormat.put("^\\d{14}$","yyyyMMddHHmmss");//20140312120534

        dateRegFormat.put("^\\d{12}$","yyyyMMddHHmm");//201403121205

        dateRegFormat.put("^\\d{10}$","yyyyMMddHH");//2014031212

        dateRegFormat.put("^\\d{8}$","yyyyMMdd");//20140312

        dateRegFormat.put("^\\d{6}$","yyyyMM");//201403

        dateRegFormat.put("^\\d{2}\\s*:\\s*\\d{2}\\s*:\\s*\\d{2}$",

                "yyyy-MM-dd-HH-mm-ss");//13:05:34  拼接当前日期

        dateRegFormat.put("^\\d{2}\\s*:\\s*\\d{2}$","yyyy-MM-dd-HH-mm");//13:05  拼接当前日期

        dateRegFormat.put("^\\d{2}\\D+\\d{1,2}\\D+\\d{1,2}$","yy-MM-dd");//14.10.18(年.月.日)

        dateRegFormat.put("^\\d{1,2}\\D+\\d{1,2}$","yyyy-dd-MM");//30.12(日.月) 拼接当前年份

        dateRegFormat.put("^\\d{1,2}\\D+\\d{1,2}\\D+\\d{4}$","dd-MM-yyyy");//12.21.2013(日.月.年)

 

        String curDate =newSimpleDateFormat("yyyy-MM-dd").format(newDate());

        DateFormat formatter1 =newSimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        DateFormat formatter2;

        String dateReplace;

        String strSuccess="";

        try{

            for(String key : dateRegFormat.keySet()) {

                if(Pattern.compile(key).matcher(dateStr).matches()) {

                    formatter2 = newSimpleDateFormat(dateRegFormat.get(key));

                    if(key.equals("^\\d{2}\\s*:\\s*\\d{2}\\s*:\\s*\\d{2}$")

                            || key.equals("^\\d{2}\\s*:\\s*\\d{2}$")) {//13:05:34 或 13:05 拼接当前日期

                        dateStr = curDate + "-"+ dateStr;

                    }elseif (key.equals("^\\d{1,2}\\D+\\d{1,2}$")) {//21.1 (日.月) 拼接当前年份

                        dateStr = curDate.substring(0,4) + "-"+ dateStr;

                    }

                    dateReplace = dateStr.replaceAll("\\D+","-");

                    // System.out.println(dateRegExpArr[i]);

                    strSuccess = formatter1.format(formatter2.parse(dateReplace));

                    break;

                }

            }

        }catch(Exception e) {

            System.err.println("-----------------日期格式无效:"+dateStr);

            thrownew Exception( "日期格式无效");

        }finally{

            returnstrSuccess;

        }

    }

    publicstatic void main(String[] args) {

        String[] dateStrArray=newString[]{

                "2014-03-12 12:05:34",

                "2014-03-12 12:05",

                "2014-03-12 12",

                "2014-03-12",

                "2014-03",

                "2014",

                "20140312120534",

                "2014/03/12 12:05:34",

                "2014/3/12 12:5:34",

                "2014年3月12日 13时5分34秒",

                "201403121205",

                "1234567890",

                "20140312",

                "201403",

                "2000 13 33 13 13 13",

                "30.12.2013",

                "12.21.2013",

                "21.1",

                "13:05:34",

                "12:05",

                "14.1.8",

                "14.10.18"  

        };

        for(inti=0;i<dateStrArray.length;i++){

            System.out.println(dateStrArray[i] +"------------------------------".substring(1,30-dateStrArray[i].length())+ FormatDate(dateStrArray[i]));

        }

         

    }

 

}