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Issue in convert calendar object to date android

I want to convert calendar object to date as follow.
int year,month,day;
mCalendarEnd = Calendar.getInstance();
year = mCalendarEnd.get(Calendar.YEAR);
month = mCalendarEnd.get(Calendar.MONTH)+1;
day = mCalendarEnd.get(Calendar.DAY_OF_MONTH);
Now convert it to date object
Date d1 = new Date(day,month,year);
when I print date object:
System.out.println("Date : "+d1.getDay()+"/"+d1.getMonth()+"/"+d1.getYear());
it should print current date but in above code it prints the wrong date. Any idea how can I solve this problem? your all suggestion are appreciable.

You need to do it like this
//Set calendar
Calendar calendar = Calendar.getInstance();
Date date1 = calendar.getTime(); // gives a date object
//To get day difference, Just an example
calendar.add(Calendar.DAY_OF_MONTH, -7);
Date date2 = calendar.getTime(); // gives a date object
long differenceInMillis = Date1.getTime() - Date2.getTime();
long differenceInDays = TimeUnit.DAYS.convert(differenceInMillis, TimeUnit.MILLISECONDS);
Or No need of date objects
Calendar calendar = Calendar.getInstance();
long date1InMillis = calendar.getTimeInMillis();
calendar.add(Calendar.DAY_OF_MONTH, -7);
long date2InMillis = calendar.getTimeInMillis();
long differenceInMillis = date1InMillis - date2InMillis;
long differenceInDays = TimeUnit.DAYS.convert(differenceInMillis, TimeUnit.MILLISECONDS);
calendar.getTimeInMillis()

calendar.getTime() returns Date object.
but if you just need today date new Date() returns today date as Date object, too.
Calendar example:
Calendar calendar = Calendar.getInstance()
Log.i("My Tag", "calendar getTime -----> " + calendar.getTime());
Output:
My Tag: calendar getTime -----> Wed Dec 05 13:03:43 GMT+03:30 2018
Date Example:
Log.i("My Tag", "new Date -----> " + new Date());
Output:
My Tag: new Date -----> Wed Dec 05 13:05:38 GMT+03:30 2018
as you see both of them have the same output.

Why you don't use just the calendar?
System.out.println("Date : " + day + "/" + month + "/" + year);
result 1/1/1900
or you want other format? but dont increment the month with 1
System.out.println("Date : " + day + "/" + new DateFormatSymbols().getMonths()[month] + "/" + year);
result 1/January/1900

Put this in your code:
Date d1 = new Date(year, month, day);
System.out.println("Date : " + d1.getDate() + "/" +d1.getMonth() + "/" + d1.getYear());
you will get the correct date.

d1=new Date(year, month, day);
System.out.println("Dt:"+d1.getDate()+"/"+d1.getMonth()+"/"+d1.getYear());

Calculating date certain period from now

I have a start date (day, month, year) and need the date say 4 weeks from that date. How can I calculate that? I know how to find the difference between two dates using Calendar so I assume I'm not too far from the answer... Thank you!!!
edit:
This is the final code I wound up using. It returns a String whose value is a date span formatted "MM/dd/YYYY - MM/dd/YYYY"
#SuppressLint("SimpleDateFormat")
private String getSessionDate(int position) {
MySession ms = mSessionList.get(position);
SimpleDateFormat format = new SimpleDateFormat("MM/dd/yyyy");
Calendar calendar = Calendar.getInstance();
calendar.set(ms.getStartYear(), ms.getStartMonth(), ms.getStartDay());
Date startDate = calendar.getTime();
String durationString = ms.getDurationString(); // Format is "## weeks"
int i = 0;
while (Character.isDigit(durationString.charAt(i))) {
i++;
}
int weeks = Integer.parseInt(durationString.substring(0, i));
calendar.add(Calendar.WEEK_OF_YEAR, weeks);
return (format.format(startDate) + " - " + format.format(calendar.getTime()));
}

You can use Calender instance for that.
Calendar calendar = Calendar.getInstance();
calendar.setTime(currentdate);
calendar.add(Calendar.DAY_OF_YEAR, no_of_days)
Date newDate = calendar.getTime();
You can calculate the date by adding or subtracting the no of days
Example :
Get date after 1 week
calendar.add(Calendar.DAY_OF_YEAR, 7);
Get date before 1 week
calendar.add(Calendar.DAY_OF_YEAR, -7);

Date date=null;
SimpleDateFormat originalFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
try {
date = originalFormat.parse(strDate); // strDate is your date from which you want to get date after 4 weeks
} catch (Exception e) {
e.printStackTrace();
}
long timeFor4week=4*7*24 * 60 * 60 * 1000; /// here 24*60*60*1000 =24 hours i.e 1 day
long timeAfter4week=date.getTime()+timeFor4week;
String finalDateString=originalFormat.format(new Date(timeAfter4week));
So you can get day after 4 weeks.

Convert Date to Year and Month

I am writing an application in which I have to display a date . Now I want to convert that date into Year and Month from the Current Date.
My Date is Like - 29/03/2017.
I want to convert this date into Year and Months.
Sorry I think you are not able to understand my question. I want the Difference of current date and above date in year and months.
Sorry for my explanation.

You can use Joda Time and compute a Period between two LocalDate values (which is what you've got here) using months and years as the units.
example
LocalDate dob = new LocalDate(1992, 12, 30);
LocalDate date = new LocalDate(2010, 12, 29);
Period period = new Period(dob, date, PeriodType.yearMonthDay());
System.out.println(period.getYears() + " years and " +
period.getMonths() + " months");

I found my answer using Calender class .
First i find the difference between two days and using that days i found the years and months.
Here i post my code, which i think help to others.
int days = Integer.parseInt(Utility.getDateDiffString("29/03/2017"));
int years = days/365;
int remainingDays = days - (365*years);
int months = remainingDays/30;
getDateDiffString() Method. In this method we need to pass end date
public static String getDateDiffString(String endDate)
{
try
{
Calendar cal = Calendar.getInstance();
SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
Date dateTwo = dateFormat.parse(endDate);
long timeOne = cal.getTimeInMillis();
long timeTwo = dateTwo.getTime();
long oneDay = 1000 * 60 * 60 * 24;
long delta = (timeTwo - timeOne) / oneDay;
if (delta > 0) {
return "" + delta + "";
}
else {
delta *= -1;
return "" + delta + "";
}
}
catch (Exception e)
{
e.printStackTrace();
}
return "";
}

if your date's format is fixed, you can do it like this :
String myDate = "29/03/2017";
String newDate = myDate.subString(6, 10) + "-" + myDate.subString(3, 5)

this method to convert the normal string to date format
String currentDateString = "02/27/2012 17:00:00";
SimpleDateFormat sd = new SimpleDateFormat("mm/dd/yyyy HH:mm:ss");
Date currentDate = sd.parse(currentDateString);
after that you get the formal method

You Should use SimpleDateFormate !
For Example:--- You can get time & Date as you want:-
Date email_date = m.getSentDate();// this is date which you are getting
DateFormat date = new SimpleDateFormat("EEE MMM yyyy");
DateFormat time = new SimpleDateFormat("hh:mm aa");
String date_str=date.format(email_date);
String time_str=time.format(email_date);

Use Java Calendar class to get year from date
Calendar c=Calendar.getInstance();
SimpleDateFormat simpleDateformat=new SimpleDateFormat("yyyy MMM");
System.out.println(simpleDateformat.format(c.getTime()));
To get difference between two date
int diffInDays = (int)( (newerDate.getTime() - olderDate.getTime())
/ (1000 * 60 * 60 * 24) )

long timeDiff = (d1.getTime() - d2.getTime());
String diff=String.format("%d year(s) %d day(s) %d hour(s) %d min(s) %d sec(s)",(TimeUnit.MILLISECONDS.toDays(timeDiff)/365),TimeUnit.MILLISECONDS.toDays(timeDiff)%365,
TimeUnit.MILLISECONDS.toHours(timeDiff)
- TimeUnit.DAYS.toHours(TimeUnit.MILLISECONDS
.toDays(timeDiff)),
TimeUnit.MILLISECONDS.toMinutes(timeDiff)
- TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS
.toHours(timeDiff)),
TimeUnit.MILLISECONDS.toSeconds(timeDiff)
- TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS
.toMinutes(timeDiff)));
System.out.println(diff);
Specify correct date here in d1 & d2.Then you will get right answer of difference

First put your Date into a String variable as:
String dateToConvert = "29/03/2017";
Instantiate Calendar as:
Calendar convertedDate = Calendar.getInstance();
Set that date to calendar
convertedDate.set(dateToConvert);<br/>
Then use this line:
String datePicked = DateFormat.getDateInstance().format(convertedDate.getTime());
Output: Mar 29, 2017

Get Date of past 7days from current in android

I am trying to fetch the date 7days prior to today's date.
I am using SimpleDateFormat to fetch today's date.
SimpleDateFormat sdf1 = new SimpleDateFormat("dd/MM/yyyy");
Please guide me through this
Updated answer which I found most useful
SimpleDateFormat sdf=new SimpleDateFormat("dd/MM/yyyy");
String currentDateandTime = sdf.format(new Date());
Date cdate=sdf.parse(currentDateandTime);
Calendar now2= Calendar.getInstance();
now2.add(Calendar.DATE, -7);
String beforedate=now2.get(Calendar.DATE)+"/"+(now2.get(Calendar.MONTH) + 1)+"/"+now2.get(Calendar.YEAR);
Date BeforeDate1=sdf.parse(beforedate);
cdate.compareTo(BeforeDate1);
Thank you for you reply

Use java.util.Calendar, set it to today's date and then subtract 7 days.
Calendar cal = GregorianCalendar.getInstance();
cal.setTime(new Date());
cal.add(Calendar.DAY_OF_YEAR, -7);
Date 7daysBeforeDate = cal.getTime();
Edit: In Java 8 it can be done much easier by using classes from java.time package:
final LocalDate date = LocalDate.now();
final LocalDate dateMinus7Days = date.minusDays(7);
//Format and display date
final String formattedDate = dateMinus7Days.format(DateTimeFormatter.ISO_LOCAL_DATE);
System.out.println(formattedDate);

You can try out this,
import java.util.Calendar;
public class AddDaysToCurrentDate {
public static void main(String[] args) {
//create Calendar instance
Calendar now = Calendar.getInstance();
System.out.println("Current date : " + (now.get(Calendar.MONTH) + 1)
+ "-"
+ now.get(Calendar.DATE)
+ "-"
+ now.get(Calendar.YEAR));
//add days to current date using Calendar.add method
now.add(Calendar.DATE,1);
System.out.println("date after one day : " + (now.get(Calendar.MONTH) + 1)
+ "-"
+ now.get(Calendar.DATE)
+ "-"
+ now.get(Calendar.YEAR));
//substract days from current date using Calendar.add method
now = Calendar.getInstance();
now.add(Calendar.DATE, -10);
System.out.println("date before 10 days : " + (now.get(Calendar.MONTH) + 1)
+ "-"
+ now.get(Calendar.DATE)
+ "-"
+ now.get(Calendar.YEAR));
}
}
/*
Typical output would be
Current date : 12-25-2007
date after one day : 12-26-2007
date before 10 days : 12-15-2007
*/

Android get date before 7 days (one week)
Date myDate = dateFormat.parse(dateString);
And then either figure out how many milliseconds you need to subtract:
Date newDate = new Date(myDate.getTime() - 604800000L); // 7 * 24 * 60 * 60 * 1000
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:
and finally
String date = dateFormat.format(newDate);

you can use this kotlin function to get any date before the current date.
/**
* get specific date before current date
* [day] number of day
* [month] number of month
* [year] number of year
* [count] number of day, month, year
*
* return date
*/
fun getBeforeDate(day: Boolean = false, month: Boolean = false, year: Boolean = false, count: Int = 0): String{
val currentCalendar = Calendar.getInstance()
val myFormat = "dd/MM/yyyy" // you can use your own date format
val sdf = SimpleDateFormat(myFormat, Locale.getDefault())
if (day){
currentCalendar.add(Calendar.DAY_OF_YEAR, -count)
}else if(month){
currentCalendar.add(Calendar.MONTH, -count)
}else if(year){
currentCalendar.add(Calendar.YEAR, -count)
}else{
// if user not provide any value then give current date
currentCalendar.add(Calendar.DAY_OF_YEAR, 0)
// or you can throw Exception
//throw Exception("Please provide at least one value")
}
return sdf.format(currentCalendar.time)
}

fun getBeforeDate(day: Boolean = false, month: Boolean = false, year: Boolean = false, count: Int = 0): String{
val currentCalendar = Calendar.getInstance()
val myFormat = "dd/MM/yyyy" // you can use your own date format
val sdf = SimpleDateFormat(myFormat, Locale.getDefault())
if (day){
currentCalendar.add(Calendar.DAY_OF_YEAR, -count)
}else if(month){
currentCalendar.add(Calendar.MONTH, -count)
}else if(year){
currentCalendar.add(Calendar.YEAR, -count)
}else{
// if user not provide any value then give current date
currentCalendar.add(Calendar.DAY_OF_YEAR, 0)
// or you can throw Exception
//throw Exception("Please provide at least one value")
}
return sdf.format(currentCalendar.time)
}

Need get Time in a 24 hour format while adding Time

I had written a function for Adding time as given below
private void Delay15Minute() {
String pkManifest = manifest.pkManifestNo;
manifest_helper = new manifest_helper(this);
cursor = manifest_helper.GetDeliveries(pkManifest);
cursor.moveToFirst();
for (int i = 0; i < cursor.getCount(); i++) {
cursor.getString(cursor.getColumnIndex("PKDelivery"));
// String
// RevisedTime=cursor.getString(cursor.getColumnIndex("RevisedEstimatedDeliveryTime"));
String RevisedTime = "12:55";
// get hour and minute from time string
StringTokenizer st1 = new StringTokenizer(RevisedTime, ":");
int j = 0;
int[] val = new int[st1.countTokens()];
// iterate through tokens
while (st1.hasMoreTokens()) {
val[j] = Integer.parseInt(st1.nextToken());
j++;
}
// call time add method with current hour, minute and minutesToAdd,
// return added time as a string
String date = addTime(val[0], val[1], 15);
// Tioast the new time
Toast.makeText(this, "date is =" + date, Toast.LENGTH_SHORT).show();
}
}
public String addTime(int hour, int minute, int minutesToAdd) {
Calendar calendar = new GregorianCalendar(1990, 1, 1, hour, minute);
calendar.add(Calendar.MINUTE, minutesToAdd);
SimpleDateFormat sdf = new SimpleDateFormat("hh:mm");
String date = sdf.format(calendar.getTime());
return date;
}
I am getting the oupt of this as 01:10 as 12 hours fromat...
I need to get it in 13:10 format ie 24 hour format.....Please help me

You used hh in your SimpleDateFormat pattern. Thats the 12 hour format. Use kk instead, that gives you the hours of the day in a 24 hour format. See SimpleDateFormat.

Simply create the instance of Calendar and get 24 hr time by,
Calendar c = Calendar.getInstance();
int Hr24=c.get(Calendar.HOUR_OF_DAY);
int Min=c.get(Calendar.MINUTE);

Use this code
long date = System.currentTimeMillis();
SimpleDateFormat date1 = new SimpleDateFormat("dd-MM-yyyy"); // for current date
SimpleDateFormat time1 = new SimpleDateFormat("kk:mm:ss"); // for 24 hour time
SimpleDateFormat time2 = new SimpleDateFormat("hh:mm:ss"); // for 12 hour time
String dateString = date1.format(date); //This will return current date in 31-12-2018 format
String timeString1 = time1.format(date); //This will return current time in 24 Hour format
String timeString2 = time2.format(date); //This will return current time in 12 Hour format
Log.e("TAG_1", "24 hour Time - " + timeString1);
Log.e("TAG_1", "24 hour Time - " + timeString1);
Log.e("TAG_1", "dd-MM-yyyy Date format - " + dateString);
than open your logcat to check result.