Date and time componet

[Kay Ra]

I have an int that represents both date and time combined in secs.
I need to separate this to 2 ints
one int having just the date no time
and 2nd int having just the time no date.

Also Do I need to convert it to gregorian calender first.


Thanks for the help

[Jeff Albertson]

That depends on how your int is formatted into date/time. So how is it formatted?

[Kay Ra]

it is unix time seconds from jan 1st 1970


thanks for your speedy reply.

[Jeff Albertson]

You are going to need a calendar. That timestamp is implicitly for the time zone UTC and you will want the time in your local time zone, not to mention handling things like daylight savings time correctly. Use Calendar.

[Kay Ra]

Jeff,

Using Calender. should I add the individual component.


tahnks

[Jeff Albertson]

What do you mean by "individual component"? Won't you start like this:

int timestampInSeconds = ...;
long timestampInMillis = 1000L * timestampInSeconds;
Calendar cal = Calendar.getInstance();
cal.setTimeInMillis(timestampInMillis);

[ May 08, 2006: Message edited by: Jeff Albertson ]

[Paul Clapham]

What you are going to do depends on what int values you want for the separate date and time components. For example you might want the int 20060508 for the date component and the int 110138 for the time component. Or you might want something completely different.

[Kay Ra]

Jeff,

This is how I achieved it. is there a better way

long timestampInMillis = 1000L * timeinseconds // has time in seconds from
Calendar cal = Calendar.getInstance();
cal.setTimeInMillis(timestampInMillis);
GregorianCalendar grecal = new GregorianCalendar(cal.YEAR, cal.MONTH, cal.DAY_OF_MONTH);
Date dt = grecal.getTime();
int dateComp =(int) dt.getTime()/1000; // has the date component
int timeComp = sch.values[0] - dateComp; // has the hr:min:sec component


thanks

[Kay Ra]

Jeff,

This line in my previous mail was cut pasted incorrectly should read as the line in bold
int timeComp = sch.values[0] - dateComp; // has the hr:min:sec component

int timeComp = timeinseconds- dateComp; // has the hr:min:sec component

[Jeff Albertson]

Looking at your code, I see *two* calendars (cal and grecal) and one big mistake: static constants YEAR, MONTH and DAY_OF_MONTH do not give you cal's year, month and date -- after all they are class constants! (One of the basic rules of Java style states that you never to access class constants in this way. Most IDES will warn you about this, too.) Try redoing this code with one calendar and try using the set method to reset the hour of day, minute, seconds and milliseconds to 0. That will wind the clock back to midnight.

[Kay Ra]

Thanks jeff for your input
This what I coded but am not sure if it is correct as in the difference I am not accurately getting the time portion


import java.util.Date;
import java.io.*;
import java.util.Calendar;
import java.lang.Integer;
import java.util.GregorianCalendar;
import java.text.DateFormat;

public class parseDate {


public static void main(String[] args) {


int givenDate = 2145916800; //1/1/2038
int givenTime = 86399; //11:59:59 PM

int totalTime = 2145916800 + 86399;


long totMilliSecs = totalTime *1000L;

System.out.println("befSet" + totMilliSecs);

Calendar cal = Calendar.getInstance();
cal.setTimeInMillis(totMilliSecs);


//testing
long gottotMilliSecs = cal.getTimeInMillis();

System.out.println("aftSet" + gottotMilliSecs);

DateFormat df1 = DateFormat.getDateTimeInstance();
Date dt = cal.getTime();
System.out.println("df1 bef making hour to zero " + df1.format(dt));


cal.set(Calendar.HOUR_OF_DAY,0);
cal.set(Calendar.MINUTE,0);
cal.set(Calendar.SECOND,0);
cal.set(Calendar.MILLISECOND,0);

dt = cal.getTime();
System.out.println("df1 setting hour:mim:sec to zero " + df1.format(dt));
long SecgottotMilliSecs = cal.getTimeInMillis();
System.out.println("aftreset" + SecgottotMilliSecs);

System.out.println("diff now " + (gottotMilliSecs - SecgottotMilliSecs));

}

[Jeff Albertson]

Your code looks okay, but your timestamp for 2038-01-01 is for UTC. Here my code adjusts the Calendar and DateFormat to work in that time zone. You can choose any time zone you like, including your JVM's default:

import java.util.Calendar;
import java.util.TimeZone;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
 
public class ParseDate {
    public static void main(String[] args) {
        TimeZone timeZone = TimeZone.getTimeZone("UTC");
        int givenDate = 2145916800; //1/1/2038
        int givenTime = 86399; //11:59:59 PM
        int totalTime = givenDate + givenTime;
        long totMillis = totalTime *1000L;
        Calendar cal = Calendar.getInstance(timeZone);
        cal.setTimeInMillis(totMillis);
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
        df.setTimeZone(timeZone);
        System.out.println("originally= " + df.format(cal.getTime()));
        cal.set(Calendar.HOUR_OF_DAY,0);
        cal.set(Calendar.MINUTE,0);
        cal.set(Calendar.SECOND,0);
        cal.set(Calendar.MILLISECOND,0);
        System.out.println("rollback=   " + df.format(cal.getTime()));
        long dateMillis = cal.getTimeInMillis();
        System.out.println("date millis=" + dateMillis);
        long timeMillis=totMillis - dateMillis;
        System.out.println("time millis=" + timeMillis);
    }
}

[Kay Ra]

Jeff very gratefull to you, Now my concepts also have gotten clearer.



thanks