Develop Reference

Getting exact time in ( HH:mm:sss a) format from milliseconds

I have to print time in my app in HH:mm:sss AM/PM from milliseconds which is 24 Hours later time .
so to get 24 hours later time to current time i used the code as
public Date roundToNext24Hour() {
Date date = new Date();
Calendar c = Calendar.getInstance();
c = new GregorianCalendar();
c.setTime(date);
c.add(Calendar.HOUR_OF_DAY, 24);
c.set(Calendar.MINUTE, 0);
c.set(Calendar.SECOND, 0);
return c.getTime();
}
now i convert this time in HH:mm:sss am/pm format
SimpleDateFormat df = new SimpleDateFormat("HH:mm:sss a");
timeString = df.format(Utility.roundToNext24Hour())
but problem is timestring is always returning time which is 12 hour later not 24 hour later.
please help..

Try below code.
Date date = new Date();
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss a");
String str = df.format(date);

How to fetch recent seven days from specific date

If the date is 2017-03-30 that i want to fetch the date from 2017-03-23 to 2017-03-30
I try to use this code let my String change to Date format
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date dateParse = sdf.parse("2017-03-30");
then i'm stuck , cause i take the reference is get the current time like this
Calendar c = Calendar.getInstance();
c.add(Calendar.DATE, -7);
//may be my dateParse should put here , but i don't know how to do
Date monday = c.getTime();//it get the current time
String preMonday = sdf.format(monday);
Is any one can teach me how to fetch these seven days ? Thanks in advance.

You can use the code below
SimpleDateFormatdateFormat = new SimpleDateFormat("dd MMM yyyy");
Calendar c = Calendar.getInstance();
String date = dateFormat.format(c.getTime());
c.add(Calendar.DATE, 7);
String date1 = dateFormat.format(c.getTime());

Parse the date:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date myDate = sdf.parse("2017-03-30");
First Solution 1) And then either figure out how many milliseconds you need to subtract:
Date newDate = new Date(myDate.getTime() - 604800000L); // 7 * 24 * 60 * 60 * 1000
Second Solution 2) Or use the API provided by the java.util.Calendar class:
Calendar calendar = Calendar.getInstance();
calendar.setTime(myDate);
calendar.add(Calendar.DAY_OF_YEAR, -7);
Date newDate = calendar.getTime();
Then, if you need to, convert it back to a String:
String date = dateFormat.format(newDate);
This answer is from here
EDIT:
If you need output as 2017-03-29 2017-03-28 2017-03-27 ...... 2017-03-23 then try below code
for(int i = 1; i <= 7; i++){
Calendar calendar = Calendar.getInstance();
calendar.setTime(myDate);
calendar.add(Calendar.DAY_OF_YEAR, -i);
Date newDate = calendar.getTime();
String date = dateFormat.format(newDate);
//here in date you can get all date from and output as 2017-03-29 2017-03-28 2017-03-27 ...... 2017-03-23
}
Hope you need this

How convert timestamp to date on android?

I want convert timestamp to date and set time in this day to 12.00.
How can I do this?
If I use this:
Date date = new Date(event.getActionDate()*1000);
I can't set hour or minutes to this date, becouse methods for this operations are deprecated.
Explanation:
I have timestamp -
1461924872 // Fri, 29 Apr 2016 10:14:32 GMT
I want change hour in this timestamp (10:14 to 00.00).

long timeInMillis = 1461877200000l;
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(timeInMillis);
System.out.println("Date1:"+calendar.getTime().toString());
calendar.set(Calendar.HOUR_OF_DAY, 0); //For 12 AM use 0 and for 12 PM use 12.
calendar.set(Calendar.MINUTE, 0);
calendar.set(Calendar.SECOND, 0);
Date date = calendar.getTime();
System.out.println("Date2:"+date.toString());

Calendar cal = Calendar.getInstance();
TimeZone tz = cal.getTimeZone();//get your local time zone.
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy hh:mm a");
sdf.setTimeZone(tz);//set time zone.
String localTime = sdf.format(new Date(time) * 1000));
Date date = new Date();
date = sdf.parse(localTime);

private String getDate(String timeStampStr){
try{
DateFormat sdf = new SimpleDateFormat("MM/dd/yyyy");
Date netDate = (new Date(Long.parseLong(timeStampStr)));
return sdf.format(netDate);
}
catch(Exception ex){
return dateInStr;
}
}
let me know if it is working?

Change timestamp into another gmt+ timestamp

Here goes my code but getting the same timestamp after changing the timezone.
TimeZone timeZone = TimeZone.getTimeZone("GMT+11");
Calendar cal1 = Calendar.getInstance();
Calendar cal2 = Calendar.getInstance();
cal1.setTimeInMillis(Long.parseLong(classListDto.get(i)
.getClassStartTime()) * THOUSAND);
cal2.setTimeInMillis(Long.parseLong(classListDto.get(i)
.getClassEndTime()) * THOUSAND);
cal1.setTimeZone(timeZone);
cal2.setTimeZone(timeZone);
long startTimestamp = cal1.getTimeInMillis();
long endTimestamp = cal2.getTimeInMillis();

Try something like this, instead of setting the timezone in your Calendar instance.
TimeZone timeZone = TimeZone.getTimeZone("GMT+11");
Calendar cal1 = Calendar.getInstance();
cal1.setTimeInMillis(Long.parseLong(classListDto.get(i).getClassStartTime()) * THOUSAND);
Date tempDate = cal1.getTime();
SimpleDateFormat df = new SimpleDateFormat();
SimpleDateFormat df1 = new SimpleDateFormat();
df.setTimeZone(timeZone);
Date gmtDate = df1.parse(df.format(tempDate)); // Put this in a Try/Catch block
long startTimestamp = gmtDate.getTime();
Hope this helps! I know its crappy to use 2 SimpleDateFormat objects though.

You can see the timezone change in your code if you do a cal1.getField(Calendar.HOUR); instead of just reading the milliseconds. Calendar seems to store the millis only in terms of UTC: http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Calendar.html#getTimeInMillis()

Current date should add 12 hours more in android

In my application i want to add 12 hours with the current date and time,then i have to show it in this format "yyyy-MM-dd HH:mm:ss". I wrote the code but unable to add 12 hours. How can i do? please help.
My code is :
Calendar cal = Calendar.getInstance();
Date date = cal.getTime();
String date1 = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).format(date);
m_tvTrackEnd.setText(date1);

The Calendar class has the add method which you can use to add certain units.
Calendar cal = Calendar.getInstance();
cal.add(Calendar.HOUR, 12);
Date date = cal.getTime();
String date1 = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).format(date);
m_tvTrackEnd.setText(date1);

How about
Calendar cal = Calendar.getInstance();
Date date = cal.getTime()+12*60*60*1000;
String date1 = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).format(date);
m_tvTrackEnd.setText(date1);

You should add the 12 hours to the Calendar object like this:
Calendar cal = Calendar.getInstance();
cal.add(Calendar.HOUR, 12)
Date date = cal.getTime();
String date1 = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).format(date);
m_tvTrackEnd.setText(date1);