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Android - How to add days to date

I have retrieved a Date from a SQLiteDatabase and have formatted it to how I want via the following;
String steepingDate = (c.getString(3));
SimpleDateFormat formatter = new SimpleDateFormat("dd/MMM/yyyy");
Date steepingdate = formatter.parse(steepingDate);
I now want to give the user the option to increase whatever date is in steepingdate by a certain amount of days that the user can input
I know you can use;
Date today = calendar.getTime();
calendar.add(Calendar.DAY_OF_YEAR, 10);
For example to add 10 days onto todays date
But how do you do it so that it uses steepingdate instead of todays date
Thanks
UPDATE;
The calendar is working as I want, but I now want to save the new data to the database, the full code is as following;
String steepingDate = (c.getString(3));
SimpleDateFormat formatter = new SimpleDateFormat("dd/MMM/yyyy");
Date steepingdate = formatter.parse(steepingDate);
Integer amountDays = Integer.parseInt(TSExtend.getText().toString());
Calendar ca = Calendar.getInstance();
ca.setTime(steepingdate);
ca.add(Calendar.DAY_OF_YEAR, amountDays);
DateFormat dateFormat = new SimpleDateFormat("dd/MMM/yyyy");
String newDate = dateFormat.format(ca);
I'm getting the error;
Bad class: class
java.util.GregorianCalendar
Any ideas?

To add 10 days to steepingdate, you can use:
Calendar calendar = Calendar.getInstance();
calendar.setTime(steepingdate);
calendar.add(Calendar.DAY_OF_YEAR, 10);
it the number is provided, through the user interface, you can use the View.OnClickListener and when onClick is fired, read the value from an EditText, and use this value instead of 10

Set the time of the calendar to your date, then add the days
Calendar cal = Calendar.getInstance();
cal.setTime(steepingdate);
cal.add(Calendar.DATE, 10);
UPDATE:
You can't directly format a Calendar, first get the Date from the Calendar, then format it.
String newDate = dateFormat.format(ca.getTime());

json to human readable date date shows one less than actual date

I convert json date to human readable date but it shows less one then actual date. I
used this code to convert it:
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
Calendar calendar = Calendar.getInstance();
Long timeInMillis = Long.valueOf(AttendanceModelList.get(position).getEmpdate());
calendar.setTimeInMillis(timeInMillis);
Date date=new Date(timeInMillis);
viewHolder.textemployeedate.setText(df.format(date));
Please help

You say as summary:
Your calendar date is one day less than expected when you try to
interprete a global timestamp of type java.util.Date as calendar
date.
This phenomenon can happen due to timezone effects or midnight change. Before viewing the technical solution, you have to ask yourself:
What is your default (system) timezone using TimeZone.getDefault()?
Do you run your code on a server which has not the expected timezone?
In which timezone do you wish to view the calendar date? (the timezone associated with your expected "actual" date)
How to specify the timezone?
java.util.Date d = ...; // from your JSON-timeInMillis?
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String tz = "Asia/Kolkata"; // or any other valid tz id
sdf.setTimeZone(TimeZone.getTimeZone(tz));
System.out.println(sdf.format(d));

System.currentTimeMillis() give wrong output android

when i am print System.currentTimeMillis()
give me :
11-03 14:47:05.400: INFO/System.out(7579): date is :: 14475410111
What is the correct procedure to get entire date with time.?

To get current date and time in Android, You can use:
Calendar c = Calendar.getInstance();
System.out.println("Current time => "+c.getTime());
Output:
Current time => Thu Nov 03 15:00:45 GMT+05:30 2011
FYI, once you have this time in 'c' object, you can use SimpleDateFormat class to get date/time in desired format.
Final Solution:
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Sring formattedDate = df.format(c.getTime()); // c is Calendar object
System.out.println("========> formatted date => "+formattedDate);
Output:
========> formatted date => 2011-11-03 15:13:37

Date now = new Date(System.currentTimeMillis());
By the way : currentTimeMillis()
Returns the current system time in milliseconds since January 1, 1970 00:00:00 UTC.

Yes This is the correct way to get the current time and date. afte that you need to convert it to desired format.
public static String getDateFromTimeStamp(String timeStamp){
return new Date(Long.parseLong(timeStamp)).toString();
}

Use the Date class.
(What makes you think that's wrong? You're asking for the time in milliseconds.)

Use SimpleDateFormat

Calendar not returning GMT

I am trying to get a calendar object set to GMT, but the getTime() always returns the time in GMT+1 (my current time). I have tried:
Calendar cal = new GregorianCalendar(TimeZone.getTimeZone("GMT"));
Calendar cal = new GregorianCalendar(TimeZone.getTimeZone("UTC"));
Calendar cal = new GregorianCalendar(TimeZone.getTimeZone("skeniver"));
They all apparently return GMT, because
cal.getTimeZone().getDisplayName()
returns "GMT+00:00"; but
cal.getTime().toString();
always displays the time in GMT+1.
Does anyone have any idea why this is happening?

You need to adjust for daylight savings. I'm not sure if this will help but it's code I use for adjusting any timezone to UTC in an app that's currently being used by a number of people around the world. I use Date instead of Calendar but it works...
Date dateTimeNow = new Date();
TimeZone tz = TimeZone.getDefault();
int currentOffsetFromUTC = tz.getRawOffset() + (tz.inDaylightTime(dateTimeNow) ? tz.getDSTSavings() : 0);
Date dateTimeNowUTC = new Date(dateTimeNow.getTime() - currentOffsetFromUTC);

If you want to in string then prefer the DateFormat or SimpleDateFormat for this
here is example
SimpleDateFormat sdf = new SimpleDateFormat(); // here you can also define your format of date for e.g. "dd/MM/yyyy z"
sdf.setTimeZone("GMT");
Calendar cal = Calendar.getInstance();
System.out.println(sdf.format(cal.getTime()));

Calendar.getTime() returns a Date object. In Java, a Date is just a holder to a long timestamp starting in the UNIX epoch.
To display a Date in a different TimeZone than the default, you can use a SimpleDateFormat.

how to add no days to date object not calendar object

I have a Date object. Now I want to add days to that Date object.
So how that can be done? Actually using Calendar object that can be done I know.
But in my case, I haven't used a calendar objects. Instead only used date object.
For Example, suppose I have a date object
Date dtStartDate=o.getStartDate();
int x=28;
Now what I want to do is to add 28 to this date object, means if the dtStartDate is 1 July 2011
then after adding 28, dtStartDate will be 29 July 2011.
Please suggest it to me.
Thanks in advance

You can add Day using below
Calendar c1 = Calendar.getInstance();
c1.add(Calendar.DAY_OF_MONTH, 1);
Here 1 is number of Day you can add.
OR
Date dtStartDate=o.getStartDate();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm");
Calendar c = Calendar.getInstance();
c.setTime(dtStartDate);
c.add(Calendar.DATE, 3); // number of days to add
String dt = sdf.format(c.getTime()); // dt is now the new date
Toast.makeText(this, "" + dt, 5000).show();
May be your problem solved.

You could add the equivilent number of milliseconds to the time retrieved from Date, e.g.:
long millis = dtStartDate.getTime();
millis = millis + x*24*60*60*1000;
Date dtEndDate = new Date();
dtEndDate.setTime(millis);

You can easily do this in two simple ways my friend. First one is:
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DAY_OF_MONTH, 1);
and the second one is:
Calendar cal = Calendar.getInstance();
cal.add(Calendar.HOUR_OF_DAY, 24);
I think you would like to find this thing. Though there are so many persons are there who choose the first method.
Thanks.