puzzle of the date output is different, 1988-07-14 will change to 1988-07-13

[endswel shui]

import java.text.ParseException;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class Test {

    public static void main(String[] args) throws ParseException {
        do1();
        System.out.println();
        do2();
        System.out.println();
        do3();
        System.out.println();
        do4();
    }

    public static void do1() throws ParseException {
        TimeZone.setDefault(TimeZone.getTimeZone("CTT"));
        java.sql.Date date = java.sql.Date.valueOf("1988-07-14");
        dodo(date);
    }

    public static void do2() throws ParseException {
        TimeZone.setDefault(TimeZone.getTimeZone("CTT"));
        java.sql.Date date = java.sql.Date.valueOf("1978-07-14");
        dodo(date);
    }

    public static void do3() throws ParseException {
        TimeZone.setDefault(TimeZone.getTimeZone("CTT"));
        java.sql.Date date = java.sql.Date.valueOf("1958-07-14");
        dodo(date);
    }

    public static void do4() throws ParseException {
        TimeZone.setDefault(TimeZone.getTimeZone("CTT"));
        java.sql.Date date = java.sql.Date.valueOf("1998-07-14");
        dodo(date);
    }

    private static void dodo(java.sql.Date date) throws ParseException {
        Date newDate = (Date) date;
        System.out.println("------" + newDate.getTimezoneOffset());
        System.out.println("0----" + newDate);
        TimeZone timeZone = TimeZone.getTimeZone("GMT+8");
        Calendar dob = Calendar.getInstance(timeZone);
        dob.setTime(newDate);
        System.out.println("1----" + String.valueOf(dob.get(Calendar.YEAR)) + "-"
                + String.valueOf(dob.get(Calendar.MONTH) + 1) + "-" 
                + String.valueOf(dob.get(Calendar.DATE)));

        java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat("yyyy-MM-dd", java.util.Locale.US);
        String mDateTime = sdf.format(newDate);
        TimeZone timeZone1 = TimeZone.getTimeZone("GMT+8");
        sdf.setTimeZone(timeZone1);
        System.out.println("2----" + sdf.parse(mDateTime));
    }

}

feel very puzzle, why the 1988-07-14 will change to 1988-07-13

-------540
0----1988-07-14
1----1988-7-13
2----Thu Jul 14 01:00:00 CST 1988

-------480
0----1978-07-14
1----1978-7-14
2----Fri Jul 14 00:00:00 CST 1978

-------480
0----1958-07-14
1----1958-7-14
2----Mon Jul 14 00:00:00 CST 1958

-------480
0----1998-07-14
1----1998-7-14
2----Tue Jul 14 00:00:00 CST 1998

[Maneesh Godbole]

Please do take out time to CarefullyChooseOneForum. This forum is for Portals and Portlets. Since your question is not portal related, I have moved it to a more appropriate forum