Calendar 1st day of week changes?

[Roger Graff]

Anyone want to guess why the first day of the week is changing on me?

import java.text.*;
import java.util.*;
 
public class TestMe{
 
    public static final boolean DEBUG = false;
 
 
 
    public static void main(String[] args ){
 
 
      TestMe test = null;
 
      try{
          test = new TestMe();
 
 
 
 
          // 2005
          Date seed3 = test.toDate( "03/27/2005", "MM/dd/yyyy" );
  test.calendarTest( seed3 );
 
  Date seed4 = test.toDate( "03/28/2005", "MM/dd/yyyy" );
          test.calendarTest( seed4 );
          test.display("");
 
          // 2005
          Date seed5 = test.toDate( "04/03/2005", "MM/dd/yyyy" );
  test.calendarTest( seed5 );
 
  Date seed6 = test.toDate( "04/04/2005", "MM/dd/yyyy" );
          test.calendarTest( seed6 );
          test.display("");
 
          //2005
          Date seed7 = test.toDate( "04/10/2005", "MM/dd/yyyy" );
  test.calendarTest( seed7 );
 
  Date seed8 = test.toDate( "04/11/2005", "MM/dd/yyyy" );
          test.calendarTest( seed8 );
          test.display("");
 
 
 
  }catch(Exception e ){
      test.display( "Exception in MAIN" );
  } // try-catch
 
    } // main
 
 
 
 
 
     private String dateToString( Date date, String pattern ) throws Exception{
 
if (DEBUG) display( "dateToString()" );
 
String dateStr = null;
 
SimpleDateFormat format = new SimpleDateFormat( pattern );
 
dateStr = format.format( date );
 
return dateStr;
 
} // dateToString
 
 
 
 
private Date toDate( String dateStr, String pattern ) throws Exception{
 
    if (DEBUG) display( "toDate()" );
 
SimpleDateFormat format = new SimpleDateFormat( pattern );
 
Date date = format.parse( dateStr );
 
return date;
 
} // toDate
 
 
 
 
public void calendarTest( Date seed ) throws Exception{
 
if (DEBUG) display( "calendarTest()" );
 
TimeZone timeZone = TimeZone.getTimeZone( "GMT-5" );
Locale locale = Locale.US;
GregorianCalendar calendar = new GregorianCalendar( timeZone, locale );
 
 
calendar.setTime( seed );
 
 
 
// what day is it right now?
//
int dayOfWeek = calendar.get( Calendar.DAY_OF_WEEK );
 
String numPostfix = getPostfix( dayOfWeek );
 
StringBuffer buffer = new StringBuffer();
buffer.append( dateToString(seed, "EEEEEEEE, MM/dd/yyyy")  );
buffer.append( " is the " );
buffer.append( dayOfWeek );
buffer.append( numPostfix );
buffer.append( " day of the week!" );
 
 
display( buffer.toString() );
 
} // calendarTest
 
 
 
 
private String getPostfix( int num ){
 
String postfix = null;
 
switch( num ){
 
case 1:
    postfix = "st";
    break;
 
case 2:
    postfix = "nd";
    break;
 
case 3:
    postfix = "rd";
    break;
 
default:
    postfix = "th";
 
} // switch
 
return postfix;
 
} // getPostfix
 
 
    private void display( String text ){
System.out.println( text );
} // display
 
 
 
} // TestMe

[ June 28, 2005: Message edited by: Roger Graff ]

[Roger Graff]

Here's the output:

Sunday, 03/27/2005 is the 1st day of the week!
Monday, 03/28/2005 is the 2nd day of the week!

Sunday, 04/03/2005 is the 1st day of the week!
Monday, 04/04/2005 is the 1st day of the week!

Sunday, 04/10/2005 is the 7th day of the week!
Monday, 04/11/2005 is the 1st day of the week!

Press any key to continue . . .

[Roger Graff]

Hmmm. I made the following changes and it seems to be working. Shame on me for not using the interface in the first place!

TimeZone timeZone = TimeZone.getTimeZone( "GMT-5" );
Locale locale = Locale.US;
GregorianCalendar calendar = new GregorianCalendar( timeZone, locale );

to

Calendar calendar = Calendar.getInstance();

[Roger Graff]

Okay - here's the culprit:

TimeZone timeZone = TimeZone.getTimeZone( "GMT-5" );