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