java正则实现各种日期格式化

package com.st.test;

 

import java.text.DateFormat;

import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.HashMap;

import java.util.regex.Pattern;

 

public class DateFormatUtil {

     

    @SuppressWarnings("finally")

    public static String FormatDate(String dateStr){

 

        HashMap<String, String> dateRegFormat = new HashMap<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 =new SimpleDateFormat("yyyy-MM-dd").format(new Date());

        DateFormat formatter1 =new SimpleDateFormat("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 = new SimpleDateFormat(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;

                    } else if (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);

            throw new Exception( "日期格式无效");

        } finally {

            return strSuccess;

        }

    }

    public static void main(String[] args) {

        String[] dateStrArray=new String[]{

                "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(int i=0;i<dateStrArray.length;i++){

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

        }

         

    }

 

}