在Java中解析这种类型的日期格式?[副本]

另一个答案,因为你似乎只专注于撕 String 另外(不是个好主意,imho。)让我们假设字符串是有效的iso8601。你能假定它会 总是 以你引用的格式,还是仅仅是8601?如果是后者,您必须处理一系列场景 these guys did .

他们提出的用于验证8601个备选方案的regex是:

^([\+-]?\d{4}(?!\d{2}\b))((-?)((0[1-9]|1[0-2])(\3([12]\d|0[1-9]|3[01]))?|W([0-4]\d|5[0-2])
 (-?[1-7])?|(00[1-9]|0[1-9]\d|[12]\d{2}|3([0-5]\d|6[1-6])))([T\s]((([01]\d|2[0-3])
 ((:?)[0-5]\d)?|24\:?00)([\.,]\d+(?!:))?)?(\17[0-5]\d([\.,]\d+)?)?
 ([zZ]|([\+-])([01]\d|2[0-3]):?([0-5]\d)?)?)?)?$ 

弄清楚如何取笑正确的捕获组让我头昏眼花。不过,以下内容适用于您的具体案例:

import java.util.regex.Matcher;
import java.util.regex.Pattern;


public class Regex8601
{
  static final Pattern r8601 = Pattern.compile("(\\d{4})-(\\d{2})-(\\d{2})T((\\d{2}):"+
                               "(\\d{2}):(\\d{2})\\.(\\d{3}))((\\+|-)(\\d{2}):(\\d{2}))");


  //2010-09-18T10:00:00.000+01:00

  public static void main(String[] args)
  {
    String thisdate = "2010-09-18T10:00:00.000+01:00";
    Matcher m = r8601.matcher(thisdate);
    if (m.lookingAt()) {
      System.out.println("Year: "+m.group(1));
      System.out.println("Month: "+m.group(2));
      System.out.println("Day: "+m.group(3));
      System.out.println("Time: "+m.group(4));
      System.out.println("Timezone: "+m.group(9));
    } else {
      System.out.println("no match");
    }
  }
}

如果您在日期和时间方面做了一些非常重要的事情,建议使用 JodaTime . 见 this extensive SO discussion ,包括 ISO8601 . 另请参见 "Should I use native data/time..." 。

下面是一个示例代码片段,取自 this example ,如果您想使用JDK SimpleDateFormat .

// 2004-06-14T19:GMT20:30Z
// 2004-06-20T06:GMT22:01Z

// http://www.cl.cam.ac.uk/~mgk25/iso-time.html
//    
// http://www.intertwingly.net/wiki/pie/DateTime
//
// http://www.w3.org/TR/NOTE-datetime
//
// Different standards may need different levels of granularity in the date and
// time, so this profile defines six levels. Standards that reference this
// profile should specify one or more of these granularities. If a given
// standard allows more than one granularity, it should specify the meaning of
// the dates and times with reduced precision, for example, the result of
// comparing two dates with different precisions.

// The formats are as follows. Exactly the components shown here must be
// present, with exactly this punctuation. Note that the "T" appears literally
// in the string, to indicate the beginning of the time element, as specified in
// ISO 8601.

//    Year:
//       YYYY (eg 1997)
//    Year and month:
//       YYYY-MM (eg 1997-07)
//    Complete date:
//       YYYY-MM-DD (eg 1997-07-16)
//    Complete date plus hours and minutes:
//       YYYY-MM-DDThh:mmTZD (eg 1997-07-16T19:20+01:00)
//    Complete date plus hours, minutes and seconds:
//       YYYY-MM-DDThh:mm:ssTZD (eg 1997-07-16T19:20:30+01:00)
//    Complete date plus hours, minutes, seconds and a decimal fraction of a
// second
//       YYYY-MM-DDThh:mm:ss.sTZD (eg 1997-07-16T19:20:30.45+01:00)

// where:

//      YYYY = four-digit year
//      MM   = two-digit month (01=January, etc.)
//      DD   = two-digit day of month (01 through 31)
//      hh   = two digits of hour (00 through 23) (am/pm NOT allowed)
//      mm   = two digits of minute (00 through 59)
//      ss   = two digits of second (00 through 59)
//      s    = one or more digits representing a decimal fraction of a second
//      TZD  = time zone designator (Z or +hh:mm or -hh:mm)
public static Date parse( String input ) throws java.text.ParseException 
{
  //NOTE: SimpleDateFormat uses GMT[-+]hh:mm for the TZ which breaks
  //things a bit.  Before we go on we have to repair this.
  SimpleDateFormat df = new SimpleDateFormat( "yyyy-MM-dd'T'HH:mm:ssz" );

  //this is zero time so we need to add that TZ indicator for 
  if ( input.endsWith( "Z" ) ) {
    input = input.substring( 0, input.length() - 1) + "GMT-00:00";
  } else {
    int inset = 6;

    String s0 = input.substring( 0, input.length() - inset );
    String s1 = input.substring( input.length() - inset, input.length() );    

    input = s0 + "GMT" + s1;
  }

  return df.parse( input );        
}

这个日期在 ISO 8601 format . 这里是 a link to a parser specific to this format 在内部使用Java SimuleDead格式解析API。

你应该用 SimpleDateFormat ,

查找示例 here 和 here 开始吧。

你可以用 javax.xml.datatype.DatatypeFactory#newXMLGregorianCalendar(String lexicalRepresentation) ( API docs )返回的xmlGregorianCalendar允许您访问所有单独的字段。

使用 SimpleDateFormat ,图案为 yyy-MM-dd'T'HH:mm:ss.SSSZ

更新 SimpleDateFormat无法与ISO 8601日期格式一起使用。而是使用, JodaTime 相反。它提供 ISOChronology 符合ISO 8601。

可以在上找到简短的示例 SO 。

最简单的解决方案是:

Date date = null;
SimpleDateFormat isoFormatWithMillis = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX");
try {
    date = isoFormatWithMillis.parse("2010-09-18T10:00:00.000+01:00");
} catch (ParseException e) {
    e.printStackTrace();
}
System.out.println(date);

这将打印 Sat Sep 18 11:00:00 CEST 2010 。

如果您使用Java 7或更早,您可以参考此 post 。

如果你正在使用Java 8,你可以这样做:

    DateTimeFormatter timeFormatter = DateTimeFormatter.ISO_DATE_TIME;
    TemporalAccessor accessor = timeFormatter.parse("2015-10-27T16:22:27.605-07:00");

    Date date = Date.from(Instant.from(accessor));
    System.out.println(date);