January 2008

Parsing 2-Digit Years with Java's SimpleDateFormat

If you have to format and parse date strings like "17.01.2008" (in this case, the German date format) with Java, you'd probably use a java.text.SimpleDateFormat:

SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yyyy");
Date now = new Date();
System.out.println( sdf.format(now) );  // something like "17.01.2008"
Date then = sdf.parse( "17.01.1908" );
System.out.println( sdf.format(then) );  // "17.01.1908"

This works as expected. But now some fancy user dares to input the year with only two digits:

SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yyyy");
Date fancy = sdf.parse( "17.01.08" );
System.out.println( sdf.format(fancy) );  // "17.01.0008" - oops!

This is a feature that one easily fails to see in the API: If the year pattern is not "y" or "yy", year numbers are parsed literally and not relatively to some century. Using the short pattern works fine for parsing, but you'll need a second pattern for output:

SimpleDateFormat input  = new SimpleDateFormat("dd.MM.yy");
SimpleDateFormat output = new SimpleDateFormat("dd.MM.yyyy");
Date ok1 = input.parse( "17.01.08" );
Date ok2 = input.parse( "17.01.2008" );
System.out.println( output.format(ok1) );  // "17.01.2008"
System.out.println( output.format(ok2) );  // "17.01.2008"

You can read (and set) the century offset using the property 2DigitYearStart.

And while we're at it: If you want to prevent SimpleDateFormat from parsing an illegal date like "32.01.2008", you'll have to switch off the lenient mode:

SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yy");
sdf.setLenient( false );
Date illegal = sdf.parse( "32.01.1908" );  // ParseException

iCab 4.0.0 and iCab 3.0.5 Public Releases

Happy New Year 2008 to you all!

In case you didn't notice: Alexander released two new public iCab versions on January 1.

iCab 4.0.0 is the very first public version of the now Cocoa and Webkit based complete rewrite of the cute little internet taxi. It requires Mac OS X 10.3.9 or later and is available as an Universal Binary version.

iCab 3.0.5 is a maintainance release of the older code base that still uses Carbon and its own rendering engine. For Max OS X it's available both as Universal Binary and PPC. For Classic Mac OS you can download a PPC release.