How to get current date and time in Android? - android

There are many questions like this on StackOverflow but no one has the answer I need. I have seen these 3 questions:
Get Value Of Day Month form Date Object in Android?
How to get month and day in android?
Get current time and date on Android
From these 3 questions I have learnt that to get date and time, we need to use Calendar. I have visited its documentation page but that is too hard to understand.
Now my question is I want to get current day i.e 12, current month i.e November, current year i.e 2014 and hour, minute, not seconds and AM or PM.
I only know till here:
Calendar c = Calendar.getInstance();
Now what should I do next?

You can customize the format you want using
DateFormat df = new SimpleDateFormat("dd MM yyyy, HH:mm");
String date = df.format(Calendar.getInstance().getTime());

Calendar calander = Calendar.getInstance();
cDay = calander.get(Calendar.DAY_OF_MONTH);
cMonth = calander.get(Calendar.MONTH) + 1;
cYear = calander.get(Calendar.YEAR);
selectedMonth = "" + cMonth;
selectedYear = "" + cYear;
cHour = calander.get(Calendar.HOUR);
cMinute = calander.get(Calendar.MINUTE);
cSecond = calander.get(Calendar.SECOND);

Use SimpleDateFormat to get date and time in desired format :
Calendar c = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("dd,MMMM,YYYY hh,mm,a");
String strDate = sdf.format(c.getTime());

Calendar localCalendar = Calendar.getInstance(TimeZone.getDefault());
Date currentTime = localCalendar.getTime();
int currentDay = localCalendar.get(Calendar.DATE);
int currentMonth = localCalendar.get(Calendar.MONTH) + 1;
int currentYear = localCalendar.get(Calendar.YEAR);
int currentDayOfWeek = localCalendar.get(Calendar.DAY_OF_WEEK);
int currentDayOfMonth = localCalendar.get(Calendar.DAY_OF_MONTH);
int CurrentDayOfYear = localCalendar.get(Calendar.DAY_OF_YEAR);
System.out.println("Current Date and time details in local timezone");
System.out.println("Current Date: " + currentTime);
System.out.println("Current Day: " + currentDay);
System.out.println("Current Month: " + currentMonth);
System.out.println("Current Year: " + currentYear);
System.out.println("Current Day of Week: " + currentDayOfWeek);
System.out.println("Current Day of Month: " + currentDayOfMonth);
System.out.println("Current Day of Year: " + CurrentDayOfYear);

tl;dr
I want to get current day i.e 12, current month i.e November, current year i.e 2014 and hour, minute, not seconds and AM or PM.
ZonedDateTime
.now(
ZoneId.of( "Pacific/Auckland" ) // Or "Asia/India", "Africa/Tunis", etc.
)
.format(
DateTimeFormatter
.ofPattern(
"dd MMMM uuuu HH:mm"
)
.withLocale(
Locale.CANADA_FRENCH // Or `Locale.US`, or `new Locale( "en" , "IN" )` for English language with India culture.
)
)
See this code run live at IdeOne.com.
28 septembre 2019 08:48
java.time
From these 3 questions I have learnt that to get date and time, we need to use Calendar.
Nope.
The Calendar class is terrible, along with Date & SimpleDateFormat and such. These classes were all supplanted years ago by the modern java.time classes defined in JSR 310.
Now my question is I want to get current day i.e 12, current month i.e November, current year i.e 2014 and hour, minute, not seconds and AM or PM.
Determining a date and time-of-day requires a time zone. For any given moment, the date varies around the globe by zone. For example, a few minutes after midnight in Paris France is a new day while still “yesterday” in Montréal Québec.
If no time zone is specified, the JVM implicitly applies its current default time zone. That default may change at any moment during runtime(!), so your results may vary. Better to specify your desired/expected time zone explicitly as an argument. If you want to depend on the JVM’s current default time zone, make your intention clear by calling ZoneId.systemDefault(). If critical, confirm the zone with your user.
Specify a proper time zone name in the format of Continent/Region, such as America/Montreal, Africa/Casablanca, or Pacific/Auckland. Never use the 2-4 letter abbreviation such as EST or IST as they are not true time zones, not standardized, and not even unique(!).
ZoneId z = ZoneId.of( "Asia/Kolkata" ) ;
Capture the current moment as seen in the wall-clock time used by the people of a certain region (a time zone).
ZonedDateTime zdt = ZonedDateTime.now( z ) ;
If you do not care about the seconds or fractional-second, truncate.
ZonedDateTime zdt = ZonedDateTime.now( z ).truncatedTo( ChronoUnit.MINUTES ) ;
Generate a string in standard ISO 8601 format, wisely extended to append the name of the time zone in square brackets.
String output = zdt.toString() ;
2019-09-28T01:42+05:30[Asia/Kolkata]
Generate a string, automatically localized.
Locale locale = new Locale( "en" , "IN" ) ; // English language, India culture.
DateTimeFormatter f = DateTimeFormatter.ofLocalizedDateTime( FormatStyle.LONG ).withLocale( locale ) ;
String output2 = zdt.format( f ) ;
28 September 2019 at 1:42:00 AM IST
See this code run live at IdeOne.com.
About java.time
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java SE 6 and Java SE 7
Most of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
Later versions of Android bundle implementations of the java.time classes.
For earlier Android (<26), the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….

public class XYZ extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.main);
Calendar c = Calendar.getInstance();
System.out.println("Current time => "+c.getTime());
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String formattedDate = df.format(c.getTime());
// formattedDate have current date/time
Toast.makeText(this, formattedDate, Toast.LENGTH_SHORT).show();
// Now we display formattedDate value in TextView
TextView txtView = new TextView(this);
txtView.setText("Current Date and Time : "+formattedDate);
txtView.setGravity(Gravity.CENTER);
txtView.setTextSize(20);
setContentView(txtView);
}
}
Calendar calander = Calendar.getInstance();
cDay = calander.get(Calendar.DAY_OF_MONTH);
cMonth = calander.get(Calendar.MONTH) + 1;
cYear = calander.get(Calendar.YEAR);
selectedMonth = "" + cMonth;
selectedYear = "" + cYear;
cHour = calander.get(Calendar.HOUR);
cMinute = calander.get(Calendar.MINUTE);
cSecond = calander.get(Calendar.SECOND);

Related

Calendar won't return date with AM/PM

I want the date in AM/PM format. Examples suggest to use a SimpleDateFormat with a or aa but this is simply not working for me.
First I set the day. Then I set view to visible for start time.
Result is format of Wed May 20 01:00:00 EDT 2020 want something like Wed May 20 01:00:00 AM EDT 2020
This applies to calendar.getTime() in the setStartTime method. The first method is only included because the day selected is linked as a global variable. Problem lies within the second method.
I could probably manually change the final date as string and convert it back but I don't want to add unnecessary complexity. I want to find out why Calendar won't succeed since this should be extremely basic.
In the end my goal is to add the date to firebase. It must be uniform across Android, IOS and Web. Therefore I need the date to be in this exact format.
Here is code:
SimpleDateFormat serviceSETimeFormat = new SimpleDateFormat("MMM dd, yyyy HH:mm aa");
public void setStartDay(View view)
{
Calendar calendar = Calendar.getInstance();
DatePickerDialog picker = new DatePickerDialog(ServiceCreation.this,
new DatePickerDialog.OnDateSetListener() {
#Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
GregorianCalendar mCal = new GregorianCalendar(year, monthOfYear, dayOfMonth);
Date dateForDisplay = mCal.getTime();
int startHourIndex = getThirdSpaceIndex(dateForDisplay.toString());
//SimpleDateFormat fmt = new SimpleDateFormat("dd-MMM-yyyy");
serviceSETimeFormat.setCalendar(mCal);
Date dateFormatted = null;
try{
dateFormatted= serviceSETimeFormat.parse(serviceSETimeFormat.format(mCal.getTime()));
currBaseStartDate=dateFormatted;
}
catch(ParseException p){
Log.wtf("SC","Parse exc34");
}
Log.wtf("SC","Here is orig date: "+dateFormatted);
//Don't show hh/mm/ss (these are held as 0)
startDayView.setText(dateForDisplay.toString().substring(0,startHourIndex));
startEndTimeWrapper.setVisibility(View.VISIBLE);
}
}, calendar.get(Calendar.YEAR),calendar.get(Calendar.MONTH),calendar.get(Calendar.DAY_OF_MONTH));
long currentTime = new Date().getTime();
picker.getDatePicker().setMinDate(currentTime);
picker.show();
}
public void setStartTime(View view) {
TimePickerDialog mTimePicker = new TimePickerDialog(ServiceCreation.this,
android.R.style.Theme_Holo_Light_Dialog_NoActionBar, new TimePickerDialog.OnTimeSetListener() {
#Override
public void onTimeSet(TimePicker timePicker, int selectedHour, int selectedMinute) {
String minuteAsS = Integer.toString(selectedMinute);
if(minuteAsS.length()==1){
minuteAsS="0"+minuteAsS;
}
if(selectedHour==0){
startTimeView.setText((selectedHour+12)+":"+minuteAsS+" AM");
}
else if(selectedHour<12){
startTimeView.setText(selectedHour+":"+minuteAsS+" AM");
}
else if(selectedHour==12){
startTimeView.setText((selectedHour)+":"+minuteAsS+" PM");
}
else{
startTimeView.setText((selectedHour-12)+":"+minuteAsS+" PM");
}
(findViewById(R.id.endTimeWrapper)).setVisibility(View.VISIBLE);
Calendar calendar = new GregorianCalendar();
calendar.setTime(currBaseStartDate);
calendar.set(Calendar.MINUTE, selectedMinute);
Log.wtf("SC","Hour before condition: "+selectedHour);
if(selectedHour>=12){
if(selectedHour!=12){
Log.wtf("SC","Decrementing hour");
selectedHour-=12;
}
Log.wtf("SC","Hour set: "+selectedHour);
calendar.set(Calendar.AM_PM,Calendar.PM);
calendar.set(Calendar.HOUR_OF_DAY,selectedHour);
}
else{
calendar.set(Calendar.AM_PM,Calendar.AM);
calendar.set(Calendar.HOUR_OF_DAY,selectedHour);
}
startTime=calendar.getTime();
Log.wtf("SC","Here is orig start time: "+startTime);
try{
startTime=serviceSETimeFormat.parse(serviceSETimeFormat.format(startTime));
Log.wtf("SC","Here is parsed start time: "+startTime);
}
catch(ParseException e){
Log.wtf("SC","START DATE PARSE EXCEPTION");
}
}
}, 12, 0, false);
mTimePicker.setTitle("Select Start Time: ");
mTimePicker.show();
}
Three points:
Even on Android and even on API levels under 26 consider using java.time, the modern Java date and time API. Calendar, GregorianCalendar, SimpleDateFormat and Date are confusing, poorly designed and long outdated classes. The modern API is so much nicer to work with.
You don’t want a Calendar or Date with AM or PM. You want to keep your model and your presentation to the user separate. In the model you want a LocalDateTime or other appropriate date-time object, and you don’t want to worry about its format, whether it uses a 12 hours or 24 hours clock. For display to your user you want date and time in a string in an appropriate format for you user, including AM or PM. This is also why your views have a setText method and no setDate method.
No Date with AM/PM format can exist. You are asking the impossible.
java.time and ThreeTenABP
Construct a LocalDate object from your three integers for year, month and day:
int year = 2020;
int monthOfYear = Calendar.MAY; // Don’t use Calendar, though
int dayOfMonth = 11;
LocalDate date = LocalDate.of(year, monthOfYear + 1, dayOfMonth);
System.out.println(date);
Output:
2020-05-11
I believe that your date picker numbers months from 0 for January through 11 for December. So we need to add 1 to the month number to convert to the way humans and LocalDate number months. I am only using the constant from the Calendar class to initialize the variable to a 0-based month number, don’t do it in your code since the value comes from the data picker. Calendar uses the same insane numbering.
To display the date back to the user format it into a string using a formatter:
DateTimeFormatter dateFormatter = DateTimeFormatter
.ofLocalizedDate(FormatStyle.MEDIUM)
.withLocale(Locale.US);
String dateForDisplay = date.format(dateFormatter);
System.out.println(dateForDisplay);
May 11, 2020
Give the appropriate locale, or leave out the call to withLocale() to rely on the locale setting of the device.
When the user selects the time:
int selectedHour = 1;
int selectedMinute = 0;
LocalTime selectedTime = LocalTime.of(selectedHour, selectedMinute);
LocalDateTime dateTime = date.atTime(selectedTime);
System.out.println(dateTime);
2020-05-11T01:00
The time can be formatted in a way that is very similar to what we did with the date:
DateTimeFormatter timeFormatter = DateTimeFormatter
.ofLocalizedTime(FormatStyle.MEDIUM)
.withLocale(Locale.US);
String timeForDisplay = selectedTime.format(timeFormatter);
System.out.println(timeForDisplay);
1:00:00 AM
Question: Doesn’t java.time require Android API level 26?
java.time works nicely on both older and newer Android devices. It just requires at least Java 6.
In Java 8 and later and on newer Android devices (from API level 26) the modern API comes built-in.
In non-Android Java 6 and 7 get the ThreeTen Backport, the backport of the modern classes (ThreeTen for JSR 310; see the links at the bottom).
On (older) Android use the Android edition of ThreeTen Backport. It’s called ThreeTenABP. And make sure you import the date and time classes from org.threeten.bp with subpackages.
Links
My thorougher answer to a similar question: want current date and time in “dd/MM/yyyy HH:mm:ss.SS” format
Oracle tutorial: Date Time explaining how to use java.time.
Java Specification Request (JSR) 310, where java.time was first described.
ThreeTen Backport project, the backport of java.time to Java 6 and 7 (ThreeTen for JSR-310).
ThreeTenABP, Android edition of ThreeTen Backport
Question: How to use ThreeTenABP in Android Project, with a very thorough explanation.

Check to see if current time is 00:00:00 [duplicate]

How can I get the current time and date in an Android app?
You could use:
import java.util.Calendar;
import java.util.Date;
Date currentTime = Calendar.getInstance().getTime();
There are plenty of constants in Calendar for everything you need.
Check the Calendar class documentation.
You can (but no longer should - see below!) use android.text.format.Time:
Time now = new Time();
now.setToNow();
From the reference linked above:
The Time class is a faster replacement
for the java.util.Calendar and
java.util.GregorianCalendar classes.
An instance of the Time class
represents a moment in time, specified
with second precision.
NOTE 1:
It's been several years since I wrote this answer,
and it is about an old, Android-specific and now deprecated class.
Google now says that
"[t]his class has a number of issues and it is recommended that GregorianCalendar is used instead".
NOTE 2: Even though the Time class has a toMillis(ignoreDaylightSavings) method, this is merely a convenience to pass to methods that expect time in milliseconds. The time value is only precise to one second; the milliseconds portion is always 000. If in a loop you do
Time time = new Time(); time.setToNow();
Log.d("TIME TEST", Long.toString(time.toMillis(false)));
... do something that takes more than one millisecond, but less than one second ...
The resulting sequence will repeat the same value, such as 1410543204000, until the next second has started, at which time 1410543205000 will begin to repeat.
If you want to get the date and time in a specific pattern you can use the following:
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault());
String currentDateandTime = sdf.format(new Date());
Or,
Date:
String currentDate = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault()).format(new Date());
Time:
String currentTime = new SimpleDateFormat("HH:mm:ss", Locale.getDefault()).format(new Date());
For those who might rather prefer a customized format, you can use:
DateFormat df = new SimpleDateFormat("EEE, d MMM yyyy, HH:mm");
String date = df.format(Calendar.getInstance().getTime());
Whereas you can have DateFormat patterns such as:
"yyyy.MM.dd G 'at' HH:mm:ss z" ---- 2001.07.04 AD at 12:08:56 PDT
"hh 'o''clock' a, zzzz" ----------- 12 o'clock PM, Pacific Daylight Time
"EEE, d MMM yyyy HH:mm:ss Z"------- Wed, 4 Jul 2001 12:08:56 -0700
"yyyy-MM-dd'T'HH:mm:ss.SSSZ"------- 2001-07-04T12:08:56.235-0700
"yyMMddHHmmssZ"-------------------- 010704120856-0700
"K:mm a, z" ----------------------- 0:08 PM, PDT
"h:mm a" -------------------------- 12:08 PM
"EEE, MMM d, ''yy" ---------------- Wed, Jul 4, '01
Actually, it's safer to set the current timezone set on the device with Time.getCurrentTimezone(), or else you will get the current time in UTC.
Time today = new Time(Time.getCurrentTimezone());
today.setToNow();
Then, you can get all the date fields you want, like, for example:
textViewDay.setText(today.monthDay + ""); // Day of the month (1-31)
textViewMonth.setText(today.month + ""); // Month (0-11)
textViewYear.setText(today.year + ""); // Year
textViewTime.setText(today.format("%k:%M:%S")); // Current time
See android.text.format.Time class for all the details.
UPDATE
As many people are pointing out, Google says this class has a number of issues and is not supposed to be used anymore:
This class has a number of issues and it is recommended that
GregorianCalendar is used instead.
Known issues:
For historical reasons when performing time calculations all
arithmetic currently takes place using 32-bit integers. This limits
the reliable time range representable from 1902 until 2037.See the
wikipedia article on the Year 2038 problem for details. Do not rely on
this behavior; it may change in the future. Calling
switchTimezone(String) on a date that cannot exist, such as a wall
time that was skipped due to a DST transition, will result in a date
in 1969 (i.e. -1, or 1 second before 1st Jan 1970 UTC). Much of the
formatting / parsing assumes ASCII text and is therefore not suitable
for use with non-ASCII scripts.
tl;dr
Instant.now() // Current moment in UTC.
…or…
ZonedDateTime.now( ZoneId.of( "America/Montreal" ) ) // In a particular time zone
Details
The other answers, while correct, are outdated. The old date-time classes have proven to be poorly designed, confusing, and troublesome.
java.time
Those old classes have been supplanted by the java.time framework.
Java 8 and later: The java.time framework is built-in.
Java 7 & 6: Use the backport of java.time.
Android: Use this wrapped version of that backport.
These new classes are inspired by the highly successful Joda-Time project, defined by JSR 310, and extended by the ThreeTen-Extra project.
See the Oracle Tutorial.
Instant
An Instant is a moment on the timeline in UTC with resolution up to nanoseconds.
Instant instant = Instant.now(); // Current moment in UTC.
Time Zone
Apply a time zone (ZoneId) to get a ZonedDateTime. If you omit the time zone your JVM’s current default time zone is implicitly applied. Better to specify explicitly the desired/expected time zone.
Use proper time zone names in the format of continent/region such as America/Montreal, Europe/Brussels, or Asia/Kolkata. Never use the 3-4 letter abbreviations such as EST or IST as they are neither standardized nor unique.
ZoneId zoneId = ZoneId.of( "America/Montreal" ); // Or "Asia/Kolkata", "Europe/Paris", and so on.
ZonedDateTime zdt = ZonedDateTime.ofInstant( instant , zoneId );
Generating Strings
You can easily generate a String as a textual representation of the date-time value. You can go with a standard format, your own custom format, or an automatically localized format.
ISO 8601
You can call the toString methods to get text formatted using the common and sensible ISO 8601 standard.
String output = instant.toString();
2016-03-23T03:09:01.613Z
Note that for ZonedDateTime, the toString method extends the ISO 8601 standard by appending the name of the time zone in square brackets. Extremely useful and important information, but not standard.
2016-03-22T20:09:01.613-08:00[America/Los_Angeles]
Custom format
Or specify your own particular formatting pattern with the DateTimeFormatter class.
DateTimeFormatter formatter = DateTimeFormatter.ofPattern( "dd/MM/yyyy hh:mm a" );
Specify a Locale for a human language (English, French, etc.) to use in translating the name of day/month and also in defining cultural norms such as the order of year and month and date. Note that Locale has nothing to do with time zone.
formatter = formatter.withLocale( Locale.US ); // Or Locale.CANADA_FRENCH or such.
String output = zdt.format( formatter );
Localizing
Better yet, let java.time do the work of localizing automatically.
DateTimeFormatter formatter = DateTimeFormatter.ofLocalizedDateTime( FormatStyle.MEDIUM );
String output = zdt.format( formatter.withLocale( Locale.US ) ); // Or Locale.CANADA_FRENCH and so on.
About java.time
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.
Where can the java.time classes be obtained?
Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
Java 9 brought some minor features and fixes.
Java SE 6 and Java SE 7
Most of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
Later versions of Android (26+) bundle implementations of the java.time classes.
For earlier Android (<26), the process of API desugaring brings a subset of the java.time functionality not originally built into Android.
If the desugaring does not offer what you need, the ThreeTenABP project adapts ThreeTen-Backport (mentioned above) to Android. See How to use ThreeTenABP….
For the current date and time, use:
String mydate = java.text.DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime());
Which outputs:
Feb 27, 2012 5:41:23 PM
Try with the following way. All formats are given below to get the date and time formats.
Calendar c = Calendar.getInstance();
SimpleDateFormat dateformat = new SimpleDateFormat("dd-MMM-yyyy hh:mm:ss aa");
String datetime = dateformat.format(c.getTime());
System.out.println(datetime);
To ge the current time you can use System.currentTimeMillis() which is standard in Java. Then you can use it to create a date
Date currentDate = new Date(System.currentTimeMillis());
And as mentioned by others to create a time
Time currentTime = new Time();
currentTime.setToNow();
You can use the code:
Calendar c = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String strDate = sdf.format(c.getTime());
Output:
2014-11-11 00:47:55
You also get some more formatting options for SimpleDateFormat from here.
Easy. You can dissect the time to get separate values for current time, as follows:
Calendar cal = Calendar.getInstance();
int millisecond = cal.get(Calendar.MILLISECOND);
int second = cal.get(Calendar.SECOND);
int minute = cal.get(Calendar.MINUTE);
// 12-hour format
int hour = cal.get(Calendar.HOUR);
// 24-hour format
int hourofday = cal.get(Calendar.HOUR_OF_DAY);
Same goes for the date, as follows:
Calendar cal = Calendar.getInstance();
int dayofyear = cal.get(Calendar.DAY_OF_YEAR);
int year = cal.get(Calendar.YEAR);
int dayofweek = cal.get(Calendar.DAY_OF_WEEK);
int dayofmonth = cal.get(Calendar.DAY_OF_MONTH);
SimpleDateFormat databaseDateTimeFormate = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
SimpleDateFormat databaseDateFormate = new SimpleDateFormat("yyyy-MM-dd");
SimpleDateFormat sdf1 = new SimpleDateFormat("dd.MM.yy");
SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy.MM.dd G 'at' hh:mm:ss z");
SimpleDateFormat sdf3 = new SimpleDateFormat("EEE, MMM d, ''yy");
SimpleDateFormat sdf4 = new SimpleDateFormat("h:mm a");
SimpleDateFormat sdf5 = new SimpleDateFormat("h:mm");
SimpleDateFormat sdf6 = new SimpleDateFormat("H:mm:ss:SSS");
SimpleDateFormat sdf7 = new SimpleDateFormat("K:mm a,z");
SimpleDateFormat sdf8 = new SimpleDateFormat("yyyy.MMMMM.dd GGG hh:mm aaa");
String currentDateandTime = databaseDateTimeFormate.format(new Date()); //2009-06-30 08:29:36
String currentDateandTime = databaseDateFormate.format(new Date()); //2009-06-30
String currentDateandTime = sdf1.format(new Date()); //30.06.09
String currentDateandTime = sdf2.format(new Date()); //2009.06.30 AD at 08:29:36 PDT
String currentDateandTime = sdf3.format(new Date()); //Tue, Jun 30, '09
String currentDateandTime = sdf4.format(new Date()); //8:29 PM
String currentDateandTime = sdf5.format(new Date()); //8:29
String currentDateandTime = sdf6.format(new Date()); //8:28:36:249
String currentDateandTime = sdf7.format(new Date()); //8:29 AM,PDT
String currentDateandTime = sdf8.format(new Date()); //2009.June.30 AD 08:29 AM
Date format Patterns
G Era designator (before christ, after christ)
y Year (e.g. 12 or 2012). Use either yy or yyyy.
M Month in year. Number of M's determine length of format (e.g. MM, MMM or MMMMM)
d Day in month. Number of d's determine length of format (e.g. d or dd)
h Hour of day, 1-12 (AM / PM) (normally hh)
H Hour of day, 0-23 (normally HH)
m Minute in hour, 0-59 (normally mm)
s Second in minute, 0-59 (normally ss)
S Millisecond in second, 0-999 (normally SSS)
E Day in week (e.g Monday, Tuesday etc.)
D Day in year (1-366)
F Day of week in month (e.g. 1st Thursday of December)
w Week in year (1-53)
W Week in month (0-5)
a AM / PM marker
k Hour in day (1-24, unlike HH's 0-23)
K Hour in day, AM / PM (0-11)
z Time Zone
For the current date and time with format, use:
In Java
Calendar c = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String strDate = sdf.format(c.getTime());
Log.d("Date", "DATE: " + strDate)
In Kotlin
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
val current = LocalDateTime.now()
val formatter = DateTimeFormatter.ofPattern("dd.MM.yyyy. HH:mm:ss")
var myDate: String = current.format(formatter)
Log.d("Date", "DATE: " + myDate)
} else {
var date = Date()
val formatter = SimpleDateFormat("MMM dd yyyy HH:mma")
val myDate: String = formatter.format(date)
Log.d("Date", "DATE: " + myDate)
}
Date formatter patterns
"yyyy.MM.dd G 'at' HH:mm:ss z" ---- 2001.07.04 AD at 12:08:56 PDT
"hh 'o''clock' a, zzzz" ----------- 12 o'clock PM, Pacific Daylight Time
"EEE, d MMM yyyy HH:mm:ss Z"------- Wed, 4 Jul 2001 12:08:56 -0700
"yyyy-MM-dd'T'HH:mm:ss.SSSZ"------- 2001-07-04T12:08:56.235-0700
"yyMMddHHmmssZ"-------------------- 010704120856-0700
"K:mm a, z" ----------------------- 0:08 PM, PDT
"h:mm a" -------------------------- 12:08 PM
"EEE, MMM d, ''yy" ---------------- Wed, Jul 4, '01
final Calendar c = Calendar.getInstance();
int mYear = c.get(Calendar.YEAR);
int mMonth = c.get(Calendar.MONTH);
int mDay = c.get(Calendar.DAY_OF_MONTH);
textView.setText("" + mDay + "-" + mMonth + "-" + mYear);
This is a method that will be useful to get date and time:
private String getDate(){
DateFormat dfDate = new SimpleDateFormat("yyyy/MM/dd");
String date=dfDate.format(Calendar.getInstance().getTime());
DateFormat dfTime = new SimpleDateFormat("HH:mm");
String time = dfTime.format(Calendar.getInstance().getTime());
return date + " " + time;
}
You can call this method and get the current date and time values:
2017/01//09 19:23
If you need the current date:
Calendar cc = Calendar.getInstance();
int year = cc.get(Calendar.YEAR);
int month = cc.get(Calendar.MONTH);
int mDay = cc.get(Calendar.DAY_OF_MONTH);
System.out.println("Date", year + ":" + month + ":" + mDay);
If you need the current time:
int mHour = cc.get(Calendar.HOUR_OF_DAY);
int mMinute = cc.get(Calendar.MINUTE);
System.out.println("time_format" + String.format("%02d:%02d", mHour , mMinute));
You can also use android.os.SystemClock.
For example SystemClock.elapsedRealtime() will give you more accurate time readings when the phone is asleep.
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
System.out.println("time => " + dateFormat.format(cal.getTime()));
String time_str = dateFormat.format(cal.getTime());
String[] s = time_str.split(" ");
for (int i = 0; i < s.length; i++) {
System.out.println("date => " + s[i]);
}
int year_sys = Integer.parseInt(s[0].split("/")[0]);
int month_sys = Integer.parseInt(s[0].split("/")[1]);
int day_sys = Integer.parseInt(s[0].split("/")[2]);
int hour_sys = Integer.parseInt(s[1].split(":")[0]);
int min_sys = Integer.parseInt(s[1].split(":")[1]);
System.out.println("year_sys => " + year_sys);
System.out.println("month_sys => " + month_sys);
System.out.println("day_sys => " + day_sys);
System.out.println("hour_sys => " + hour_sys);
System.out.println("min_sys => " + min_sys);
Use:
Time time = new Time();
time.setToNow();
System.out.println("time: " + time.hour + ":" + time.minute);
This will give you, for example, "12:32".
Remember to import android.text.format.Time;.
You can simply use the following code:
DateFormat df = new SimpleDateFormat("HH:mm"); // Format time
String time = df.format(Calendar.getInstance().getTime());
DateFormat df1 = new SimpleDateFormat("yyyy/MM/dd"); // Format date
String date = df1.format(Calendar.getInstance().getTime());
Current time and date in Android with the format
Calendar c = Calendar.getInstance();
System.out.println("Current dateTime => " + c.getTime());
SimpleDateFormat df = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss a");
String formattedDate = df.format(c.getTime());
System.out.println("Format dateTime => " + formattedDate);
Output
I/System.out: Current dateTime => Wed Feb 26 02:58:17 GMT+05:30 2020
I/System.out: Format dateTime => 26-02-2020 02:58:17 AM
For a customized time and date format:
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZZZZ",Locale.ENGLISH);
String cDateTime = dateFormat.format(new Date());
The output is in this format:
2015-06-18T10:15:56-05:00
Time now = new Time();
now.setToNow();
Try this works for me as well.
You can obtain the date by using:
Time t = new Time(Time.getCurrentTimezone());
t.setToNow();
String date = t.format("%Y/%m/%d");
This will give you a result in a nice form, as in this example: "2014/02/09".
Well, I had problems with some answers by the API, so I fused this code:
Time t = new Time(Time.getCurrentTimezone());
t.setToNow();
String date1 = t.format("%Y/%m/%d");
Date date = new Date(System.currentTimeMillis());
SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm aa", Locale.ENGLISH);
String var = dateFormat.format(date);
String horafecha = var+ " - " + date1;
tvTime.setText(horafecha);
Output:
03:25 PM - 2017/10/03
Java
Long date=System.currentTimeMillis();
SimpleDateFormat dateFormat =new SimpleDateFormat("dd / MMMM / yyyy - HH:mm", Locale.getDefault());
String dateStr = dateFormat.format(date);
Kotlin
date if milliseconds and 13 digits(hex to date)
val date=System.currentTimeMillis() //here the date comes in 13 digits
val dtlong = Date(date)
val sdfdate = SimpleDateFormat(pattern, Locale.getDefault()).format(dtlong)
Date Formatter
"dd / MMMM / yyyy - HH:mm" -> 29 / April / 2022 - 12:03
"dd / MM / yyyy" -> 29 / 03 / 2022
"dd / MMM / yyyy" -> 29 / Mar / 2022 (shortens the month)
"EEE, d MMM yyyy HH:mm:ss" -> Wed, 4 Jul 2022 12:08:56
Date todayDate = new Date();
todayDate.getDay();
todayDate.getHours();
todayDate.getMinutes();
todayDate.getMonth();
todayDate.getTime();
Try This
String mytime = (DateFormat.format("dd-MM-yyyy hh:mm:ss", new java.util.Date()).toString());
You should use the Calender class according to the new API. The Date class is deprecated now.
Calendar cal = Calendar.getInstance();
String date = "" + cal.get(Calendar.DATE) + "-" + (cal.get(Calendar.MONTH)+1) + "-" + cal.get(Calendar.YEAR);
String time = "" + cal.get(Calendar.HOUR_OF_DAY) + ":" + cal.get(Calendar.MINUTE);
The below method will return the current date and time in a String, Use a different time zone according to your actual time zone. I've used GMT.
public static String GetToday(){
Date presentTime_Date = Calendar.getInstance().getTime();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
return dateFormat.format(presentTime_Date);
}

Android converting calendar in one TimeZone to local TimeZone

I am using following code to convert timezone (GMT-3) to device local timezone.
int hour=17,minute=0,day=12,month=6,year=2014;
Calendar cal = new GregorianCalendar(TimeZone.getTimeZone("GMT-3"));
cal.set(year, (month-1), day,hour,minute);
cal.setTimeZone(TimeZone.getDefault());
Log.d("Time", cal.get(Calendar.DATE)+"/"+cal.get(Calendar.MONTH)+"/"+cal.get(Calendar.YEAR)+" , "+cal.get(Calendar.HOUR_OF_DAY)+":"+cal.get(Calendar.MINUTE)+" "+cal.get(Calendar.AM_PM));
My local timezone is GMT+5:30
Expected result is
Time 13/5/2014, 1:30 0
But I am getting the result
12/5/2014 , 13:30 1
Sorry for you, GregorianCalendar is sometimes the hell. Your problem is following:
If you immediately set the timezone after having set the fields for year, month etc. then this mutable calendar class will only shift the timezone retaining the already set fields containing the local time. Those fields for year, month etc. will NOT be recalculated. This behaviour causes a shift on the global timeline represented by cal.getTime(), too.
In order to force the calendar object to recalculate the fields you need to call a getter. Watch out for following code and especially remove the comment marks to see the effect.
int hour = 17, minute = 0, day = 12, month = 6, year = 2014;
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mmZ");
TimeZone tz1 = TimeZone.getTimeZone("GMT-3");
sdf.setTimeZone(tz1);
Calendar cal = new GregorianCalendar(tz1);
cal.set(year, (month - 1), day, hour, minute);
// System.out.println(sdf.format(cal.getTime()));
// System.out.println("Hour=" + cal.get(Calendar.HOUR_OF_DAY));
TimeZone tz2 = TimeZone.getTimeZone("GMT+0530");
sdf.setTimeZone(tz2);
cal.setTimeZone(tz2);
System.out.println(sdf.format(cal.getTime()));
System.out.println("Hour=" + cal.get(Calendar.HOUR_OF_DAY));
Output with comment-disabled lines:
2014-06-12T17:00+0530
Hour=17
Output with enabled lines after having removed the comment marks:
2014-06-12T17:00-0300
Hour=17
2014-06-13T01:30+0530
Hour=1

Formatting a calendar date

I just want the date to show up like so:
Saturday, May 26, 2012 at 10:42 PM
Here's my code so far:
Calendar calendar = Calendar.getInstance();
String theDate = calendar.get(Calendar.MONTH) + " " + calendar.get(Calendar.DAY_OF_MONTH) + " " + calendar.get(Calendar.YEAR);
lastclick.setText(getString(R.string.lastclick) + " " + theDate);
This shows the numbers of the month, day, and year, but there's got to be a better way of doing this? Isn't there some simple way of doing this like using PHP's date() function?
Calendar calendar = Calendar.getInstance();
SimpleDateFormat format = new SimpleDateFormat("EEEE, MMMM d, yyyy 'at' h:mm a");
System.out.println(format.format(calendar.getTime()));
Running the above code outputs the current time (e.g., Saturday, May 26, 2012 at 11:03 PM).
See the Android documentation for SimpleDateFormat for more information.
The format specification of SimpleDateFormat is similar to that of PHP's date function:
echo date("l, M j, Y \a\\t g:i A");
You're right. Compared to the Java code, the PHP code is much more succinct.
Use the below to format the date as required. Refer this LINK
Calendar calendar = Calendar.getInstance();
lastclick.setText(getString(R.string.lastclick) + " " + String.format("%1$tA %1$tb %1$td %1$tY at %1$tI:%1$tM %1$Tp", calendar));
Where %1$tA for staurday,
%1$tb for May,
and so on...
This is actually a fairly subtle problem to get right, and I've not seen another answer here on SO that addresses both:
The Calendar's time zone (which means that it might be showing a different date than local)
The device's Locale (which affects the "right" way to format dates)
The previous answers to this question ignore locale, and other answers that involve conversion to a Date ignore the time zone. So here's a more complete, general solution:
Calendar cal = Calendar.getInstance(); // the value to be formatted
java.text.DateFormat formatter = java.text.DateFormat.getDateInstance(
java.text.DateFormat.LONG); // one of SHORT, MEDIUM, LONG, FULL, or DEFAULT
formatter.setTimeZone(cal.getTimeZone());
String formatted = formatter.format(cal.getTime());
Note that you need to use java.text.DateFormat here, not Android's own (confusingly-named) android.text.format.DateFormat.
Even simpler answer:
SimpleDateFormat.getDateTimeInstance().format(cal.getTime())
For me this works perfectly:
val cal = Calendar.getInstance()
val pattern = "EEEE, MMMM d, yyyy 'at' h:mm a"
val primaryLocale = getLocales(resources.configuration).get(0)
val dateFormat = SimpleDateFormat(dateFormatPattern, primaryLocale)
val formatedDate: String = dateFormat.format(cal.time)
I use this solution which is a mix of the other answers and also includes time
You can customize the DateFormat.SHORT parts to other constants to show more/different details
Short leads to this on my device: 17/07/2021 04:11
You can simply pass Calendar.getInstance() to get the current time
fun formatDateTime(calendar: Calendar):String{
val formatter = DateFormat.getDateTimeInstance(DateFormat.SHORT,DateFormat.SHORT)
formatter.timeZone = calendar.timeZone
return formatter.format(calendar.time)
}

How to conert local time to UTC time in android [duplicate]

Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
When I create a new Date object, it is initialized to the current time but in the local timezone. How can I get the current date and time in GMT?
tl;dr
Instant.now() // Capture the current moment in UTC.
Generate a String to represent that value:
Instant.now().toString()
2016-09-13T23:30:52.123Z
Details
As the correct answer by Jon Skeet stated, a java.util.Date object has no time zone†. But its toString implementation applies the JVM’s default time zone when generating the String representation of that date-time value. Confusingly to the naïve programmer, a Date seems to have a time zone but does not.
The java.util.Date, j.u.Calendar, and java.text.SimpleDateFormat classes bundled with Java are notoriously troublesome. Avoid them. Instead, use either of these competent date-time libraries:
java.time.* package in Java 8
Joda-Time
java.time (Java 8)
Java 8 brings an excellent new java.time.* package to supplant the old java.util.Date/Calendar classes.
Getting current time in UTC/GMT is a simple one-liner…
Instant instant = Instant.now();
That Instant class is the basic building block in java.time, representing a moment on the timeline in UTC with a resolution of nanoseconds.
In Java 8, the current moment is captured with only up to milliseconds resolution. Java 9 brings a fresh implementation of Clock captures the current moment in up to the full nanosecond capability of this class, depending on the ability of your host computer’s clock hardware.
It’s toString method generates a String representation of its value using one specific ISO 8601 format. That format outputs zero, three, six or nine digits digits (milliseconds, microseconds, or nanoseconds) as necessary to represent the fraction-of-second.
If you want more flexible formatting, or other additional features, then apply an offset-from-UTC of zero, for UTC itself (ZoneOffset.UTC constant) to get a OffsetDateTime.
OffsetDateTime now = OffsetDateTime.now( ZoneOffset.UTC );
Dump to console…
System.out.println( "now.toString(): " + now );
When run…
now.toString(): 2014-01-21T23:42:03.522Z
About java.time
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java SE 6 and Java SE 7
Most of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
Later versions of Android bundle implementations of the java.time classes.
For earlier Android (<26), the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….
The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.
Joda-Time
UPDATE: The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
Using the Joda-Time 3rd-party open-source free-of-cost library, you can get the current date-time in just one line of code.
Joda-Time inspired the new java.time.* classes in Java 8, but has a different architecture. You may use Joda-Time in older versions of Java. Joda-Time continues to work in Java 8 and continues to be actively maintained (as of 2014). However, the Joda-Time team does advise migration to java.time.
System.out.println( "UTC/GMT date-time in ISO 8601 format: " + new org.joda.time.DateTime( org.joda.time.DateTimeZone.UTC ) );
More detailed example code (Joda-Time 2.3)…
org.joda.time.DateTime now = new org.joda.time.DateTime(); // Default time zone.
org.joda.time.DateTime zulu = now.toDateTime( org.joda.time.DateTimeZone.UTC );
Dump to console…
System.out.println( "Local time in ISO 8601 format: " + now );
System.out.println( "Same moment in UTC (Zulu): " + zulu );
When run…
Local time in ISO 8601 format: 2014-01-21T15:34:29.933-08:00
Same moment in UTC (Zulu): 2014-01-21T23:34:29.933Z
For more example code doing time zone work, see my answer to a similar question.
Time Zone
I recommend you always specify a time zone rather than relying implicitly on the JVM’s current default time zone (which can change at any moment!). Such reliance seems to be a common cause of confusion and bugs in date-time work.
When calling now() pass the desired/expected time zone to be assigned. Use the DateTimeZone class.
DateTimeZone zoneMontréal = DateTimeZone.forID( "America/Montreal" );
DateTime now = DateTime.now( zoneMontréal );
That class holds a constant for UTC time zone.
DateTime now = DateTime.now( DateTimeZone.UTC );
If you truly want to use the JVM’s current default time zone, make an explicit call so your code is self-documenting.
DateTimeZone zoneDefault = DateTimeZone.getDefault();
ISO 8601
Read about ISO 8601 formats. Both java.time and Joda-Time use that standard’s sensible formats as their defaults for both parsing and generating strings.
† Actually, java.util.Date does have a time zone, buried deep under layers of source code. For most practical purposes, that time zone is ignored. So, as shorthand, we say java.util.Date has no time zone. Furthermore, that buried time zone is not the one used by Date’s toString method; that method uses the JVM’s current default time zone. All the more reason to avoid this confusing class and stick with Joda-Time and java.time.
java.util.Date has no specific time zone, although its value is most commonly thought of in relation to UTC. What makes you think it's in local time?
To be precise: the value within a java.util.Date is the number of milliseconds since the Unix epoch, which occurred at midnight January 1st 1970, UTC. The same epoch could also be described in other time zones, but the traditional description is in terms of UTC. As it's a number of milliseconds since a fixed epoch, the value within java.util.Date is the same around the world at any particular instant, regardless of local time zone.
I suspect the problem is that you're displaying it via an instance of Calendar which uses the local timezone, or possibly using Date.toString() which also uses the local timezone, or a SimpleDateFormat instance, which, by default, also uses local timezone.
If this isn't the problem, please post some sample code.
I would, however, recommend that you use Joda-Time anyway, which offers a much clearer API.
SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
//Local time zone
SimpleDateFormat dateFormatLocal = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");
//Time in GMT
return dateFormatLocal.parse( dateFormatGmt.format(new Date()) );
This definitely returns UTC time: as String and Date objects !
static final String DATE_FORMAT = "yyyy-MM-dd HH:mm:ss";
public static Date getUTCdatetimeAsDate() {
// note: doesn't check for null
return stringDateToDate(getUTCdatetimeAsString());
}
public static String getUTCdatetimeAsString() {
final SimpleDateFormat sdf = new SimpleDateFormat(DATE_FORMAT);
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
final String utcTime = sdf.format(new Date());
return utcTime;
}
public static Date stringDateToDate(String StrDate) {
Date dateToReturn = null;
SimpleDateFormat dateFormat = new SimpleDateFormat(DATEFORMAT);
try {
dateToReturn = (Date)dateFormat.parse(StrDate);
}
catch (ParseException e) {
e.printStackTrace();
}
return dateToReturn;
}
Calendar c = Calendar.getInstance();
System.out.println("current: "+c.getTime());
TimeZone z = c.getTimeZone();
int offset = z.getRawOffset();
if(z.inDaylightTime(new Date())){
offset = offset + z.getDSTSavings();
}
int offsetHrs = offset / 1000 / 60 / 60;
int offsetMins = offset / 1000 / 60 % 60;
System.out.println("offset: " + offsetHrs);
System.out.println("offset: " + offsetMins);
c.add(Calendar.HOUR_OF_DAY, (-offsetHrs));
c.add(Calendar.MINUTE, (-offsetMins));
System.out.println("GMT Time: "+c.getTime());
Actually not time, but it's representation could be changed.
SimpleDateFormat f = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");
f.setTimeZone(TimeZone.getTimeZone("UTC"));
System.out.println(f.format(new Date()));
Time is the same in any point of the Earth, but our perception of time could be different depending on location.
This works for getting UTC milliseconds in Android.
Calendar c = Calendar.getInstance();
int utcOffset = c.get(Calendar.ZONE_OFFSET) + c.get(Calendar.DST_OFFSET);
Long utcMilliseconds = c.getTimeInMillis() + utcOffset;
Calendar aGMTCalendar = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
Then all operations performed using the aGMTCalendar object will be done with the GMT time zone and will not have the daylight savings time or fixed offsets applied
Wrong!
Calendar aGMTCalendar = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
aGMTCalendar.getTime(); //or getTimeInMillis()
and
Calendar aNotGMTCalendar = Calendar.getInstance(TimeZone.getTimeZone("GMT-2"));aNotGMTCalendar.getTime();
will return the same time. Idem for
new Date(); //it's not GMT.
This code prints the current time UTC.
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;
public class Test
{
public static void main(final String[] args) throws ParseException
{
final SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
f.setTimeZone(TimeZone.getTimeZone("UTC"));
System.out.println(f.format(new Date()));
}
}
Result
2013-10-26 14:37:48 UTC
Here is what seems to be incorrect in Jon Skeet's answer. He said:
java.util.Date is always in UTC. What makes you think it's in local
time? I suspect the problem is that you're displaying it via an
instance of Calendar which uses the local timezone, or possibly using
Date.toString() which also uses the local timezone.
However, the code:
System.out.println(new java.util.Date().getHours() + " hours");
gives the local hours, not GMT (UTC hours), using no Calendar and no SimpleDateFormat at all.
That is why is seems something is incorrect.
Putting together the responses, the code:
System.out.println(Calendar.getInstance(TimeZone.getTimeZone("GMT"))
.get(Calendar.HOUR_OF_DAY) + " Hours");
shows the GMT hours instead of the local hours -- note that getTime.getHours() is missing because that would create a Date() object, which theoretically stores the date in GMT, but gives back the hours in the local time zone.
If you want a Date object with fields adjusted for UTC you can do it like this with Joda Time:
import org.joda.time.DateTimeZone;
import java.util.Date;
...
Date local = new Date();
System.out.println("Local: " + local);
DateTimeZone zone = DateTimeZone.getDefault();
long utc = zone.convertLocalToUTC(local.getTime(), false);
System.out.println("UTC: " + new Date(utc));
You can use:
Calendar aGMTCalendar = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
Then all operations performed using the aGMTCalendar object will be done with the GMT time zone and will not have the daylight savings time or fixed offsets applied. I think the previous poster is correct that the Date() object always returns a GMT it's not until you go to do something with the date object that it gets converted to the local time zone.
SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyy-MM-dd");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
System.out.println(dateFormatGmt.format(date));
Here is my implementation of toUTC:
public static Date toUTC(Date date){
long datems = date.getTime();
long timezoneoffset = TimeZone.getDefault().getOffset(datems);
datems -= timezoneoffset;
return new Date(datems);
}
There's probably several ways to improve it, but it works for me.
You can directly use this
SimpleDateFormat dateFormatGmt = new SimpleDateFormat("dd:MM:yyyy HH:mm:ss");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
System.out.println(dateFormatGmt.format(new Date())+"");
Here an other suggestion to get a GMT Timestamp object:
import java.sql.Timestamp;
import java.util.Calendar;
...
private static Timestamp getGMT() {
Calendar cal = Calendar.getInstance();
return new Timestamp(cal.getTimeInMillis()
-cal.get(Calendar.ZONE_OFFSET)
-cal.get(Calendar.DST_OFFSET));
}
Here is another way to get GMT time in String format
String DATE_FORMAT = "EEE, dd MMM yyyy HH:mm:ss z" ;
final SimpleDateFormat sdf = new SimpleDateFormat(DATE_FORMAT);
sdf.setTimeZone(TimeZone.getTimeZone("GMT"));
String dateTimeString = sdf.format(new Date());
With:
Calendar cal = Calendar.getInstance();
Then cal have the current date and time.
You also could get the current Date and Time for timezone with:
Calendar cal2 = Calendar.getInstance(TimeZone.getTimeZone("GMT-2"));
You could ask cal.get(Calendar.DATE); or other Calendar constant about others details.
Date and Timestamp are deprecated in Java. Calendar class it isn't.
Sample code to render system time in a specific time zone and a specific format.
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
public class TimZoneTest {
public static void main (String[] args){
//<GMT><+/-><hour>:<minutes>
// Any screw up in this format, timezone defaults to GMT QUIETLY. So test your format a few times.
System.out.println(my_time_in("GMT-5:00", "MM/dd/yyyy HH:mm:ss") );
System.out.println(my_time_in("GMT+5:30", "'at' HH:mm a z 'on' MM/dd/yyyy"));
System.out.println("---------------------------------------------");
// Alternate format
System.out.println(my_time_in("America/Los_Angeles", "'at' HH:mm a z 'on' MM/dd/yyyy") );
System.out.println(my_time_in("America/Buenos_Aires", "'at' HH:mm a z 'on' MM/dd/yyyy") );
}
public static String my_time_in(String target_time_zone, String format){
TimeZone tz = TimeZone.getTimeZone(target_time_zone);
Date date = Calendar.getInstance().getTime();
SimpleDateFormat date_format_gmt = new SimpleDateFormat(format);
date_format_gmt.setTimeZone(tz);
return date_format_gmt.format(date);
}
}
Output
10/08/2011 21:07:21
at 07:37 AM GMT+05:30 on 10/09/2011
at 19:07 PM PDT on 10/08/2011
at 23:07 PM ART on 10/08/2011
Just to make this simpler, to create a Date in UTC you can use Calendar :
Calendar.getInstance(TimeZone.getTimeZone("UTC"));
Which will construct a new instance for Calendar using the "UTC" TimeZone.
If you need a Date object from that calendar you could just use getTime().
Converting Current DateTime in UTC:
DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
DateTimeZone dateTimeZone = DateTimeZone.getDefault(); //Default Time Zone
DateTime currDateTime = new DateTime(); //Current DateTime
long utcTime = dateTimeZone.convertLocalToUTC(currDateTime .getMillis(), false);
String currTime = formatter.print(utcTime); //UTC time converted to string from long in format of formatter
currDateTime = formatter.parseDateTime(currTime); //Converted to DateTime in UTC
public static void main(String args[]){
LocalDate date=LocalDate.now();
System.out.println("Current date = "+date);
}
This worked for me, returns the timestamp in GMT!
Date currDate;
SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
SimpleDateFormat dateFormatLocal = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");
long currTime = 0;
try {
currDate = dateFormatLocal.parse( dateFormatGmt.format(new Date()) );
currTime = currDate.getTime();
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
The Simple Function that you can use:
Edit: this version uses the modern java.time classes.
private static final DateTimeFormatter FORMATTER
= DateTimeFormatter.ofPattern("dd-MM-uuuu HH:mm:ss z");
public static String getUtcDateTime() {
return ZonedDateTime.now(ZoneId.of("Etc/UTC")).format(FORMATTER);
}
Return value from the method:
26-03-2022 17:38:55 UTC
Original function:
public String getUTC_DateTime() {
SimpleDateFormat dateTimeFormat = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss z");
dateTimeFormat.setTimeZone(TimeZone.getTimeZone("UTC"));//gmt
return dateTimeFormat.format(new Date());
}
return of above function:
26-03-2022 08:07:21 UTC
To put it simple. A calendar object stores information about time zone but when you perform cal.getTime() then the timezone information will be lost. So for Timezone conversions I will advice to use DateFormat classes...
this is my implementation:
public static String GetCurrentTimeStamp()
{
Calendar cal=Calendar.getInstance();
long offset = cal.getTimeZone().getOffset(System.currentTimeMillis());//if you want in UTC else remove it .
return new java.sql.Timestamp(System.currentTimeMillis()+offset).toString();
}
Use this Class to get ever the right UTC Time from a Online NTP Server:
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
class NTP_UTC_Time
{
private static final String TAG = "SntpClient";
private static final int RECEIVE_TIME_OFFSET = 32;
private static final int TRANSMIT_TIME_OFFSET = 40;
private static final int NTP_PACKET_SIZE = 48;
private static final int NTP_PORT = 123;
private static final int NTP_MODE_CLIENT = 3;
private static final int NTP_VERSION = 3;
// Number of seconds between Jan 1, 1900 and Jan 1, 1970
// 70 years plus 17 leap days
private static final long OFFSET_1900_TO_1970 = ((365L * 70L) + 17L) * 24L * 60L * 60L;
private long mNtpTime;
public boolean requestTime(String host, int timeout) {
try {
DatagramSocket socket = new DatagramSocket();
socket.setSoTimeout(timeout);
InetAddress address = InetAddress.getByName(host);
byte[] buffer = new byte[NTP_PACKET_SIZE];
DatagramPacket request = new DatagramPacket(buffer, buffer.length, address, NTP_PORT);
buffer[0] = NTP_MODE_CLIENT | (NTP_VERSION << 3);
writeTimeStamp(buffer, TRANSMIT_TIME_OFFSET);
socket.send(request);
// read the response
DatagramPacket response = new DatagramPacket(buffer, buffer.length);
socket.receive(response);
socket.close();
mNtpTime = readTimeStamp(buffer, RECEIVE_TIME_OFFSET);
} catch (Exception e) {
// if (Config.LOGD) Log.d(TAG, "request time failed: " + e);
return false;
}
return true;
}
public long getNtpTime() {
return mNtpTime;
}
/**
* Reads an unsigned 32 bit big endian number from the given offset in the buffer.
*/
private long read32(byte[] buffer, int offset) {
byte b0 = buffer[offset];
byte b1 = buffer[offset+1];
byte b2 = buffer[offset+2];
byte b3 = buffer[offset+3];
// convert signed bytes to unsigned values
int i0 = ((b0 & 0x80) == 0x80 ? (b0 & 0x7F) + 0x80 : b0);
int i1 = ((b1 & 0x80) == 0x80 ? (b1 & 0x7F) + 0x80 : b1);
int i2 = ((b2 & 0x80) == 0x80 ? (b2 & 0x7F) + 0x80 : b2);
int i3 = ((b3 & 0x80) == 0x80 ? (b3 & 0x7F) + 0x80 : b3);
return ((long)i0 << 24) + ((long)i1 << 16) + ((long)i2 << 8) + (long)i3;
}
/**
* Reads the NTP time stamp at the given offset in the buffer and returns
* it as a system time (milliseconds since January 1, 1970).
*/
private long readTimeStamp(byte[] buffer, int offset) {
long seconds = read32(buffer, offset);
long fraction = read32(buffer, offset + 4);
return ((seconds - OFFSET_1900_TO_1970) * 1000) + ((fraction * 1000L) / 0x100000000L);
}
/**
* Writes 0 as NTP starttime stamp in the buffer. --> Then NTP returns Time OFFSET since 1900
*/
private void writeTimeStamp(byte[] buffer, int offset) {
int ofs = offset++;
for (int i=ofs;i<(ofs+8);i++)
buffer[i] = (byte)(0);
}
}
And use it with:
long now = 0;
NTP_UTC_Time client = new NTP_UTC_Time();
if (client.requestTime("pool.ntp.org", 2000)) {
now = client.getNtpTime();
}
If you need UTC Time "now" as DateTimeString use function:
private String get_UTC_Datetime_from_timestamp(long timeStamp){
try{
Calendar cal = Calendar.getInstance();
TimeZone tz = cal.getTimeZone();
int tzt = tz.getOffset(System.currentTimeMillis());
timeStamp -= tzt;
// DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",Locale.getDefault());
DateFormat sdf = new SimpleDateFormat();
Date netDate = (new Date(timeStamp));
return sdf.format(netDate);
}
catch(Exception ex){
return "";
}
}
and use it with:
String UTC_DateTime = get_UTC_Datetime_from_timestamp(now);
If you want to avoid parsing the date and just want a timestamp in GMT, you could use:
final Date gmt = new Timestamp(System.currentTimeMillis()
- Calendar.getInstance().getTimeZone()
.getOffset(System.currentTimeMillis()));
public class CurrentUtcDate
{
public static void main(String[] args) {
Date date = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss");
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
System.out.println("UTC Time is: " + dateFormat.format(date));
}
}
Output:
UTC Time is: 22-01-2018 13:14:35
You can change the date format as needed.
Current date in the UTC
Instant.now().toString().replaceAll("T.*", "");

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