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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());

comparing milliseconds with data in android

I have data+time in saved in database (sq lite) in milliseconds, now I want to get data from sq-lite of a specific date and I have date in this format "26-December-2012", how to compare this with milliseconds.
what should be the query to fetch data from database?

You have to convert the milliseconds into date format then compare two dates
convert into date formate
public static String getDate(long milliSeconds, String dateFormat)
{`enter code here`
// Create a DateFormatter object for displaying date in specified format.
DateFormat formatter = new SimpleDateFormat(dateFormat);
// Create a calendar object that will convert the date and time value in milliseconds to date.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(milliSeconds);
return formatter.format(calendar.getTime());
}
compare dates
SimpleDateFormat curFormater = new SimpleDateFormat("dd/MM/yyyy");
Date date1 = curFormater.parse(date1Str);
Date date2 = curFormater.parse(date2Str);
if (date1.before(date2))
{
}

Simply create a new Calendar with the timeInMilliseconds data from the database.
So, if you have the time in a column called date and the data is in a table called myTable the query to get that is:
select date from myTable ... other constraints
In android, simply use the long value retrieved from the database to construct a new Calendar:
Calendar cal = new Calendar.getInstance();
cal.setTimeInMillis(timeInMsFromDatabase);
Once you have a Calendar object, you can retrieve the values you want with the get(int field) method.
Or, you can use the DateFormat class.
Make sense?

I hope this will be helpful to you
public long getDateLong(String dateString, String format) throws ParseException
{
SimpleDateFormat f = new SimpleDateFormat(format);
Date d = f.parse(dateString);
return d.getTime();
}
//
long timeMillis; // Your long time millis
boolean compare = timeMillis > getDateLong("26-December-2012", "dd-MMMM-yyyy");

How to database.update the date value

I have a date value in this format: yyyy-MM-dd kk:mm:ss
So from this line data = params.getString("data"); i get the date I have set before in another activity.
So with a button click I need to add + 10 minutes to the date value.
I do know its through the value.put("...",...); but as I don't want to change the DATE only the TIME of the value. How should do I do it?

Use an instance of Calendar:
SimpleDateFormat currentDate = new SimpleDateFormat("yyyy-MM-dd kk:mm:ss");
Calendar c = Calendar.getInstance();
c.setTime(currentDate.parse(data)); // your date value
c.add(Calendar.MINUTE,10);
newDate = c.getTime()

How to get Date object in “YYYY-MM-DD” format in android

I have a requirement that I need to compare two Dates. One Date will come from DB which is String in "YYYY-DD-MM" firm and I need to compare this String Date with current Date.
for this I am converting Date String into Date object.
Now I need current Date also in "YYYY-MM-DD" format and it should be Date object so that I can use.compareTo() method compare two dates..
Please help me how to do that...

Date cDate = new Date();
String fDate = new SimpleDateFormat("yyyy-MM-dd").format(cDate);

You can do it in following way
// pick current system date
Date dt = new Date();
// set format for date
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
// parse it like
String check = dateFormat.format(dt);
System.out.println("DATE TO FROM DATEBASE " +
arrayOfStringDate[d].toString());
System.out.println("CURRENT DATE " + check);
// and compare like
System.out.println("compare "+
arrayOfStringDate[d].toString().equals(check));

Calendar c = Calendar.getInstance();
SimpleDateFormat tf = new SimpleDateFormat("yyyy-MM-dd");
String time=DB time;
Date parseTime= tf.parse(time);
Integer dayNow=c.getTime().getDate();
Integer dayDb=parseTime.getDate();
then you can compare dayNow and dayDb.

If your current date is actually an instance of the java.util.Date class, you don't need to specify a format for it; it's just a millisecond value that represents a specific moment in time.
You can get the current date like so:
Date currentDate = new Date();

You can use 2 ways:
DateFormat object. Use parse method.
Make your own parser of the Date. I mean, you convert the year, month and day in an integer each, and use Date constructor to get the Date.

How to Compare system date with mydate in android 2.1?

in my Android application, i am taking date and time from database. but i am not able to get the date in the "Date" Format from the database into my application, the date is in string format, so i am not able to compare the system date to database date.
if i convert the system date into string then i am not able to update the date into the database in recurring case. i also want to update the database date if the system date and database date is matched.
how can i achieve this is android.
Thanks in advance.

You can convert String to Date like this:
String str = "12/12/1912";
SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
Date date = formatter.parse(str);
And back to String
SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
System.out.println("Date is : " + formatter.format(date));
And Date has before and after methods and can be compared to each other.
By the way there is also a library called Joda, you can also check it out.

Try this code:
Calendar c = Calendar.getInstance();
System.out.println("Current time => " + c.getTime());
SimpleDateFormat df = new SimpleDateFormat("dd-MMMM");
formattedDate = df.format(c.getTime());