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Get current Date with custom time

I have some time Strings such as "09:00" and "17:30" and I need to check if the current time is between that range.
I thought I could make this comparison:
SimpleDateFormat format = new SimpleDateFormat("HH:mm");
Date now = new Date();
Date begin;
Date end;
begin = format.parse(begin_string);
end = format.parse(end_string);
if (now.compareTo(begin) > 0 && end.compareTo(now) > 0)
return true;
else
return false;
Turns out that when I parse the strings, the times are parsed correctly, but the date is set to Jan 1st 1970. This way, the code will always return false.
I'd like to know how can I set begin and end to the current date, but with the times from their strings.

You could also just reuse your format object for current time like this way:
SimpleDateFormat format = new SimpleDateFormat("HH:mm");
Date now = new Date();
String time = format.format(now); // format to wall time loosing current date
System.out.println(time);
now = format.parse(time); // reparse wall time
System.out.println(now);
So you transform now to 1970 using implicitly the standard time zone of your system and can then use it for direct comparisons with begin and end.
Date begin = format.parse("09:00");
Date end = format.parse("21:30");
return (begin.before(now) && end.after(now)); // open-bounded interval

Get current time, Calendar.getInstance();
Get another 2 instance of current time, and set time fields based on your input
For example:
Calendar.set(Calendar.HOUR_OF_DAY, 1);
and invoke compare() on the boundry of time

You should really use a Calendar. Then you can individually set the hours and minutes from values parsed from the string. Then get the time in milliseconds and compare those.
Date now = new Date();
Calendar cal = Calendar.getInstance();
cal.setTime(now);
cal.set(Calendar.HOUR_OF_DAY, hours);
cal.set(Calendar.MINUTE, minutes);
long time = cal.getTimeInMillis();
You could also use the wonderful Joda library. In my opinion Joda is a much better way to work with Dates and Times.

The bundled java.util.Date & .Calendar classes are notoriously troublesome. Avoid them. Use either Joda-Time library or the new java.time package found in Java 8 (inspired by Joda-Time, defined by JSR 310).
If you truly do not care about time zone or date, use either the Joda-Time LocalTime class or the java.time LocalTime class.
Caution: Naïve programmers often think they need only local time and can therefore ignore time zones, but then live to regret that position.
Joda-Time
If your times are in proper ISO 8601 format (24-hours, correct number of digits), then you can directly pass the string inputs to the constructor of LocalTime without bothering to parse. That class has a built-in ISO 8601 style parser.
String inputStart = "09:00";
String inputStop = "17:30";
LocalTime start = new LocalTime( inputStart );
LocalTime stop = new LocalTime( inputStop );
LocalTime now = LocalTime.now();
// Comparing using Half-Open logic, where beginning is inclusive and ending is exclusive.
boolean isNowContainedWithinInterval = ( ( now.isEqual( start ) ) || ( now.isAfter( start ) ) ) && ( now.isBefore( stop ) );
Dump to console…
System.out.println( "start: " + start );
System.out.println( "stop: " + stop );
System.out.println( "now: " + now );
System.out.println( "isNowContainedWithinInterval: " + isNowContainedWithinInterval );
When run…
start: 09:00:00.000
stop: 17:30:00.000
now: 12:42:06.567
isNowContainedWithinInterval: true
In the real-world, I would add an assertion test proving the stop time is later than the start time, to validate inputs.

Format a Date object with DateFormat in Java

I'm trying to learn about Date objects and the DateFormat class and I keep getting an error in the examples I'm trying to do. The goal is to get a due date by adding 30 days to a pretend invoice date, and then to format that due date. The dueDate method, I believe, is correct, but I'm having trouble formatting it properly.
Here is the first thing I have that takes the invoice date and adds 30 days to it.
public Date getDueDate()
{
Calendar cal = new GregorianCalendar();
cal.setTime(getInvoiceDate());
cal.add(Calendar.DATE, 30);
Date dueDate = cal.getTime();
return dueDate;
}
The next part is where I'm having the trouble, as it keeps telling me it expects a Date object but is receiving a String and I'm not sure why, as I'm supplying a Date object.
public Date getFormattedDueDate()
{
Date dueDate = getDueDate();
DateFormat shortDate = DateFormat.getDateInstance(DateFormat.SHORT);
return shortDate.format(dueDate);
}
Can anyone help me figure out why it's telling me that my supplied variable (dueDate) is a String when it's coded as a Date object?

format(Date date) Formats a Date into a date/time String.

Shamse is right
shortDate.format(dueDate);
returns a String, you can easly fix this changing your return type
public String getFormattedDueDate()
{
Date dueDate = getDueDate();
DateFormat shortDate = DateFormat.getDateInstance(DateFormat.SHORT);
return shortDate.format(dueDate);
}

The answer by Shamse is correct.
For the heck of it, here's the same kind of code but:
Written using the third-party library, Joda-Time 2.3
Care taken with time zones. Depending on default time zones is risky.
// © 2013 Basil Bourque. This source code may be used freely forever by anyone taking full responsibility for doing so.
java.util.Date date = new Date(); // = getInvoiceDate();
org.joda.time.DateTime invoiceStoredDateTime = new org.joda.time.DateTime( date );
// Set to desired time zone. Ideally that invoice date was stored in UTC.
// Time Zone list: http://joda-time.sourceforge.net/timezones.html
org.joda.time.DateTimeZone denverTimeZone = org.joda.time.DateTimeZone.forID( "America/Denver" );
org.joda.time.DateTime invoiceZonedDateTime = invoiceStoredDateTime.toDateTime( denverTimeZone );
// Call method .withTimeAtStartOfDay() to set the time component to first moment of the day.
org.joda.time.DateTime dueDateInThirtyDays = invoiceZonedDateTime.plusDays( 30 ).withTimeAtStartOfDay();
org.joda.time.DateTime dueDateInOneMonth = invoiceZonedDateTime.plusMonths( 1 ).withTimeAtStartOfDay(); // Smart month calculation, aiming at same day number of month.
// Style – Specify a character of 'S' for short style, 'M' for medium, 'L' for long, and 'F' for full. First for date, second for time.
// A date or time may be omitted by specifying a style character '-'.
String dueDateAsString = org.joda.time.format.DateTimeFormat.forStyle("S-").withLocale( Locale.US ).print( dueDateInThirtyDays );
org.joda.time.DateTime dueDateInUtcForStorage = dueDateInThirtyDays.toDateTime( org.joda.time.DateTimeZone.UTC );
Show values on the console:
System.out.println( "date: " + date );
System.out.println( "invoiceZonedDateTime: " + invoiceZonedDateTime );
System.out.println( "dueDateInThirtyDays: " + dueDateInThirtyDays );
System.out.println( "dueDateInOneMonth: " + dueDateInOneMonth );
System.out.println( "dueDateAsString: " + dueDateAsString );
System.out.println( "dueDateInUtcForStorage: " + dueDateInUtcForStorage );
When run…
date: Thu Nov 28 13:39:05 PST 2013
invoiceZonedDateTime: 2013-11-28T14:39:05.125-07:00
dueDateInThirtyDays: 2013-12-28T00:00:00.000-07:00
dueDateInOneMonth: 2013-12-28T00:00:00.000-07:00
dueDateAsString: 12/28/13
dueDateInUtcForStorage: 2013-12-28T07:00:00.000Z

Changing timezone without changing time in Java

I'm receiving a datetime from a SOAP webservice without timzone information. Hence, the Axis deserializer assumes UTC. However, the datetime really is in Sydney time. I've solved the problem by substracting the timezone offset:
Calendar trade_date = trade.getTradeDateTime();
TimeZone est_tz = TimeZone.getTimeZone("Australia/Sydney");
long millis = trade_date.getTimeInMillis() - est_tz.getRawOffset();
trade_date.setTimeZone( est_tz );
trade_date.setTimeInMillis( millis );
However, I'm not sure if this solution also takes daylight saving into account. I think it should, because all operations are on UTC time. Any experiences with manipulating time in Java? Better ideas on how to solve this problem?

I pity the fool who has to do dates in Java.
What you have done will almost certainly go wrong around the daylight savings transitions. The best way to to it is probably to create a new Calendar object, set the Timezone on it, and then set all of the fields individually, so year, month, day, hour, minute, second, getting the values from the Date object.
Edit:
To keep the everyone happy, you should probably do this:
Calendar utcTime = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
Calendar sydneyTime = Calendar.getInstance(TimeZone.getTimeZone("Australia/Sydney");
utcTime.setTime(trade_date);
for (int i = 0; i < Calendar.FIELD_COUNT; i++) {
sydneyTime.set(i, utcTime.get(i));
}
Then you won't be using any deprecated methods.

I want to thank the person for responce 6. This was a great start for me and an approach I did not consider. There are some addtional steps required to bring it to production code level. In particular observe the steps required for DST_OFFSET and ZONE_OFFSET. I want to share the solution I came up with.
This takes the time from the input Calendar object, copies it to the output time, sets the new time zone to the output. This is used when taking time literally from the database and setting the Time Zone without changing the time.
public static Calendar setNewTimeZoneCopyOldTime( Calendar inputTime,
TimeZone timeZone ) {
if( (inputTime == null) || (timeZone == null) ) { return( null ); }
Calendar outputTime = Calendar.getInstance( timeZone );
for( int i = 0; i < Calendar.FIELD_COUNT; i++ ) {
if( (i != Calendar.ZONE_OFFSET) && (i != Calendar.DST_OFFSET) ) {
outputTime.set(i, inputTime.get(i));
}
}
return( (Calendar) outputTime.clone() );
}

However, I'm not sure if this solution
also takes daylight saving into
account. I think it should, because
all operations are on UTC time.
Yes, you should take the daylight saving into account, since it affects the offset to UTC.
Any experiences with manipulating time in Java? Better ideas on how to solve this problem?
Joda-Time is a better time API. Maybe the following snippet could be of help :
DateTimeZone zone; // TODO : get zone
DateTime fixedTimestamp = new DateTime(year, monthOfYear, dayOfMonth, hourOfDay, minuteOfHour, secondOfMinute, millisOfSecond, zone);
JodaTime types are immutable which is also a benefit.

I normally do it this way
Calendar trade_date_utc = trade.getTradeDateTime();
TimeZone est_tz = TimeZone.getTimeZone("Australia/Sydney");
Calendar trade_date = Calendar.GetInstance(est_tz);
trade_date.setTimeInMillis( millis );

Are you getting an ISO 8601 style string from that messed-up Web Service? If so, the Joda-Time 2.3 library makes this very easy.
If you are getting an ISO 8601 string without any time zone offset, you pass a time zone object to the DateTime constructor.
DateTimeZone timeZone = DateTimeZone.forID( "Australia/Sydney" );
String input = "2014-01-02T03:00:00"; // Note the lack of time zone offset at end.
DateTime dateTime = new DateTime( input, timeZone );
Dump to console…
System.out.println( "dateTime: " + dateTime );
When run…
dateTime: 2014-01-02T03:00:00.000+11:00

#Test
public void tzTest() {
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS Z");
TimeZone tz1 = TimeZone.getTimeZone("Europe/Moscow");
Calendar cal1 = Calendar.getInstance(tz1);
long l1 = cal1.getTimeInMillis();
df.setTimeZone(tz1);
System.out.println(df.format(cal1.getTime()));
System.out.println(l1);
TimeZone tz2 = TimeZone.getTimeZone("Africa/Douala");
Calendar cal2 = Calendar.getInstance(tz2);
long l2 = l1 + tz1.getRawOffset() - tz2.getRawOffset();
cal2.setTimeInMillis(l2);
df.setTimeZone(tz2);
System.out.println(df.format(cal2.getTime()));
System.out.println(l2);
assertNotEquals(l2, l1);
}
Running CalendarTest
2016-06-30 19:09:16.522 +0300
1467302956522
2016-06-30 19:09:16.522 +0100
1467310156522
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.137 sec

I've decided to reparse the datetime string received with the correct time zone set. This should also consider daylight saving:
public class DateTest {
private static SimpleDateFormat soapdatetime = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
/**
* #param args
*/
public static void main(String[] args) {
TimeZone oztz = TimeZone.getTimeZone("Australia/Sydney");
TimeZone gmtz = TimeZone.getTimeZone("GMT");
Calendar datetime = Calendar.getInstance( gmtz );
soapdatetime.setTimeZone( gmtz );
String soap_datetime = soapdatetime.format( datetime.getTime() );
System.out.println( soap_datetime );
soapdatetime.setTimeZone( oztz );
datetime.setTimeZone( oztz );
try {
datetime.setTime(
soapdatetime.parse( soap_datetime )
);
} catch (ParseException e) {
e.printStackTrace();
}
soapdatetime.setTimeZone( gmtz );
soap_datetime = soapdatetime.format( datetime.getTime() );
System.out.println( soap_datetime );
}
}

how to find out whether or not a date is 1 year before today's date in java

In java, how can I find out if a specific date is within 1 year of today's date.
I have the following but not sure if this is the best approach.
String date = "01/19/2005";
DateFormat df = new SimpleDateFormat("dd/MM/yyyy");
Date lastExamTakenDate = null;
Calendar todaysDateMinus1Year = Calendar.getInstance();
todaysDateMinus1Year.add(Calendar.YEAR, -1);
if (date!=null)
{
try {
lastExamTakenDate = df.parse(date);
if (lastExamTakenDate.before(todaysDateMinus1Year.getTime()))
hasToTakeExam = true;
} catch (ParseException ex) {
//exception
}
}

The java.util.Date & .Calendar classes bundled with Java are notoriously troublesome. Avoid them. Use either Joda-Time or the new java.time package bundled with Java 8 (and inspired by Joda-Time).
Joda-Time
If you are certain you want date only without time or time zone, use the LocalDate class (found in both Joda-Time and java.time).
Note the use of a time zone when asking for the current date. The date varies depending on where you are at on earth at the moment. If you fail to specify a date, the JVM’s default time zone will be used. Generally better to specify.
Here is some example code using Joda-Time 2.3.
String input = "01/19/2005";
DateTimeFormatter formatter = DateTimeFormat.forPattern( "MM/dd/yyyy" );
LocalDate localDate = LocalDate.parse( input, formatter );
DateTimeZone timeZone = DateTimeZone.forID( "Europe/Paris" );
LocalDate now = LocalDate.now( timeZone );
LocalDate yearAgo = now.minusYears( 1 );
boolean withinYearAgo = ( ( localDate.isAfter( yearAgo ) ) & ( localDate.isBefore( now ) ) );
Dump to console…
System.out.println( "input: " + input );
System.out.println( "localDate: " + localDate );
System.out.println( "now: " + now );
System.out.println( "yearAgo: " + yearAgo );
System.out.println( "withinYearAgo: " + withinYearAgo );
When run…
input: 01/19/2005
localDate: 2005-01-19
now: 2014-04-10
yearAgo: 2013-04-10
withinYearAgo: false
You might want to add a test for "or is equal to" depending on your definition of "within last year".

If you call getTime() on a date object it will return a long with milliseconds since epoch (jan 1. 1970). Checking if a date is within the last year is then a simple matter of creating one date object with a date one year ago and doing comparison on the long values (someDate > aYearAgo). Alternatively you can use the after() method on a calendar object. To create a calendar/date object with a value one year ago you can use calObj.add(Calendar.YEAR, -1).

I believe something like this will get you the start of the calendar day so that time of day is not a factor.
GregorianCalendar calToday = new GregorianCalendar();
GregorianCalendar oneYearAgoTodayAtMidnight = new GregorianCalendar(calToday.get(Calendar.YEAR) - 1, calToday.get(Calendar.MONTH), calToday.get(Calendar.DATE));

This approach ignores leap-years (and other calendar-caused oddities), but is very straightforward:
public boolean isWithinAYear(Date inputDate) {
Date d = new Date() // Get "now".
long dLong = d.getTime();
// You could multiply this next line out and use a single constant,
// I didn't do that for clarity (and the compiler will optimize it
// out for us anyhow.)
long oneYearAgo = dLong - (365 * 24 * 60 * 60 * 1000);
return inputDate.getTime() > oneYearAgo;
}
Your solution using GregorianCalendar is technically more correct.

This woks perfectly.
public class X {
public static Date date ;
public static Date date1 ;
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
Calendar cal = Calendar.getInstance();
cal.add(Calendar.YEAR, 0);
boolean time;
date = cal.getTime();
System.out.println(date);
time = withinYear(date);
System.out.println(time);
}
private static boolean result;
public static boolean withinYear(Date inputDate)
{
Calendar todaysDateMinus1Year = Calendar.getInstance();
todaysDateMinus1Year.add(Calendar.YEAR, -1);
date1 = todaysDateMinus1Year.getTime();
if (inputDate.before(date1))
result= true;
return result;
}

How to get all dates of sundays in a particular year in Java?

I am seriously looking for this code...I am new programmer.
Actually I want to make all dates with flag, which all are sunday in a particular year.
Please, I am eagerly waiting for your response....

Create a new calendar. Set the time to 1/1/yyyy and some time. Check if the current date is a Sunday and roll forward one day until it is. That's the first Sunday of the year. Roll forward 7 days until the year no longer matches, marking as you go.

Study the the docs of java.util.Calendar carefully.

If i was doing it I would use Joda Time to find the first Sunday in the year using LocalDate. Create 1st of Jan and then add 1 day until it is a Sunday, then add 7 days until your run out of year.
LocalDate date = new LocalDate(YEAR, 1, 1);
while ( date.dayOfWeek() != 7 )
{
date = date.addDays(1);
}
while ( date.year() == YEAR )
{
date = date.addDays(7);
}
Or something like that.

Something like this should work.
int year = 2009;
Calendar cal = new GregorianCalendar(year, Calendar.JANUARY, 1);
for (int i = 0, inc = 1; i < 366 && cal.get(Calendar.YEAR) == year; i+=inc) {
if (cal.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
// this is a sunday
cal.add(Calendar.DAY_OF_MONTH, 7);
inc = 7;
} else {
cal.add(Calendar.DAY_OF_MONTH, 1);
}
}

This is an example code using java.util.Calendar and java.util.GregorianCalendar that prints out each Sunday of the year 2009.
A lot of optimizing can be done in formatting the date, but i'll leave that as an exercise for you.
import java.util.Calendar;
import java.util.GregorianCalendar;
public class Test
{
public static void main(String[] args)
{
int year =2009;
int dayOfWeek = Calendar.SUNDAY;
String dayOfWeekString = "Sunday";
// instantiate Calender and set to first Sunday of 2009
Calendar cal = new GregorianCalendar();
cal.set(2009, 0, 1, 0, 0); cal.getTime();
cal.set(Calendar.DAY_OF_WEEK, dayOfWeek); cal.getTime();
int i = 1;
while (cal.get(Calendar.YEAR) == 2009)
{
System.out.println(dayOfWeekString + " " + i + ": " + cal);
cal.add(Calendar.DAY_OF_MONTH, 7);
i++;
}
}
}
As you can see, TiGz's way of using Joda Time is a lot simpler.

List arrList = new ArrayList();
SimpleDateFormat format1 = new SimpleDateFormat("dd-M-yyyy");
Date date = null;
Calendar cal = Calendar.getInstance();
for (int i = 0; i <= 51; i++)
{
try
{
cal.add(Calendar.WEEK_OF_YEAR, +1);
cal.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
String formatted = format1.format(cal.getTime());
date = format1.parse(formatted);
arrList.add(date);
} catch (Exception e) {
e.printStackTrace();
}
}

java.time
Java 8 and later comes with the new java.time package. Inspired by Joda-Time, defined by JSR 310, extended by the ThreeTen-Extra project. These new classes supplant the notoriously troublesome java.util.Date/.Calendar & java.text.SimpleDateFormat and such.
Note that we specify a time zone, crucial for determining a date. For example, a new day dawns earlier in Paris than in Montréal.
ZoneId zoneId = ZoneId.of( "America/Montreal" ); // Time zone is crucial in determining the date. A new day dawns earlier in Paris than In Montréal, for example.
You would write this code to use only LocalDate without any time-of-day. But in business, the full date-time is often more useful. So my example here uses ZonedDateTime.
To be neat, I want the time-of-day set to first moment of the day. You might assume that means 00:00:00.0 but not always because of anomalies such as Daylight Saving Time. To soft-code this first-moment, we want to call the atStartOfDay method found on LocalDate. So we start with LocalDate, then use that method to get a ZonedDateTime object.
Again, note that we specify a time zone when getting today’s date. A very common mistake is to omit time zone. When omitted, the JVM’s current default time zone will be implicitly applied. That means your results can vary by machine or by admin’s settings. Even worse, any code in any thread of any app within this JVM can make a call to change that default time zone at any moment during runtime while your app executes! So always specify rather than rely implicitly on current default.
LocalDate today = LocalDate.now( zoneId ); // We want a ZonedDateTime, but starting with a LocalDate in order to get first moment of the day (see next line).
ZonedDateTime todayStart = today.atStartOfDay( zoneId ); // Set time-of-day to first moment of this date, just to be neat. Usually that time is '00:00:00.0' but not always.
The java.time framework includes some handy TemporalAdjustors to get first day of year, and from there, the first Sunday of that month.
ZonedDateTime firstOfThisYear = todayStart.with( TemporalAdjusters.firstDayOfYear( ) );
ZonedDateTime zdtFirstOfNextYear = firstOfThisYear.with( TemporalAdjusters.firstDayOfNextYear( ) );
ZonedDateTime firstSundayOfThisYear = firstOfThisYear.with( TemporalAdjusters.dayOfWeekInMonth( 1, DayOfWeek.SUNDAY ) );
Now we are set to loop through all the weeks of the year. We increment a week at a time until we find ourselves in the next year. We collect each Sunday in a List.
ZonedDateTime zdt = firstSundayOfThisYear; // Var changing throughout loop.
List< ZonedDateTime > sundays = new ArrayList<>( 53 ); // Set initial capacity to maximum number of values.
while ( zdt.isBefore( zdtFirstOfNextYear ) ) {
// Handle this iteration.
sundays.add( zdt );
System.out.println( "Sunday # " + sundays.size( ) + " : " + zdt );
// Prepare next iteration.
zdt = zdt.plusWeeks( 1 );
}
When run.
Sunday # 1 : 2015-01-04T00:00-05:00[America/Montreal]
Sunday # 2 : 2015-01-11T00:00-05:00[America/Montreal]
…
Sunday # 51 : 2015-12-20T00:00-05:00[America/Montreal]
Sunday # 52 : 2015-12-27T00:00-05:00[America/Montreal]

A year has approximately 365 days, so the Big-O's n is pretty manageable. I'd say just iterate from the beginning of the year through to the last day of the year, and check if each day is a Sunday or not.
You need at least Calendar.get(), Calendar.DAY_OF_WEEK and Calendar.SUNDAY

I recently developed [Lamma Date] which is designed to serve this type of use cases.
Following code will print out all Sundays in 2014:
List<Date> sundays2014 = Dates.from(2014, 1, 1).to(2014, 12, 31).byWeek().on(DayOfWeek.SUNDAY).build();
for(Date date: sundays2014) {
System.out.println(date);
}

**this will give u all Sundays of the year **
invented By me and friend Hemant
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
public class Test {
public static void main(String[] args) {
SimpleDateFormat format =new SimpleDateFormat("dd-MMM-yyyy");
String DATE_FORMAT = "yyyy MM dd";
SimpleDateFormat sdf = new SimpleDateFormat(DATE_FORMAT);
Calendar c1 = Calendar.getInstance(); // today
String y=sdf.format(c1.getTime());
String years=y.substring(0,4);
int year=Integer.parseInt(years);
//Connection con=null;
Calendar cal = new GregorianCalendar(year, Calendar.JANUARY, 1);
for (int i = 0, inc = 1; i <366 && cal.get(Calendar.YEAR) == year; i+=inc) {
if (cal.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
// this is a sunday
String frm="";
frm=format.format(cal.getTime());
//System.out.println("From :"+frm);
System.out.println("the value of the sunday is "+format.format(cal.getTime()));
cal.add(Calendar.DAY_OF_MONTH, 7);
} else {
cal.add(Calendar.DAY_OF_MONTH, 1);
}
}
}
}