comparing the two times is greater or lesser in java

Question

  Date date1= new java.util.Date();
                  java.sql.Date Sqldob = new java.sql.Date(date1.getTime());
                  System.out.println("date" +Sqldob);

                  Time Sqldob1 = new Time(date1.getTime());
                  System.out.println("User Time: " +Sqldob1);
                  String yourTime="09:30:00"; 

                  SimpleDateFormat ra = new SimpleDateFormat("HH:mm:ss");
                  Date yourDate = ra.parse(yourTime);
                  Time sqlTime3 = new Time(yourDate.getTime());
                  System.out.println("your time"+sqlTime3);

                  if(Sqldob1.before(sqlTime3)){
                     Sqldob1 = sqlTime3; 
                     System.out.println("inside loop");
                  }

In the code above I am comparing two time variables for equality, but it is giving me the same value -1 for all the types of input

Please see http://stackoverflow.com/questions/2592501/compare-dates-in-java — fluminis, Sep 27 '13 at 08:28
as per your code it just can return -1 for **one** type of input: `sqlTime3.compareTo(Sqldob1)` since it's the only place where you make the comparison. besides, please, be kind and shows also what are the potential values for `Sqldob1`... — Alonso Dominguez, Sep 27 '13 at 08:30
sqldob1 will be given from user that is from java.util.date it may vary above or below 9:30:00 thnk u — user2767354, Sep 27 '13 at 08:33
To the usage: a loop is something that can repeat. An `if` statement cannot repeat in itself, so it is not a loop. — Ole V.V., Jul 07 '17 at 10:55

Rahul · Accepted Answer · 2013-09-27T11:11:28.517

10

You need to use the Date#before(Date),Date#after(Date) and Date#equals(Date) methods for basic date comparisons.

E.g:

Date d1 = new Date();
Date d2 = new Date();

if(d1.after(d2)){
    // Do something
}

if(d1.before(d2)){
    // Do something
}

if(d1.equals(d2)){
    // Do something
}

You can use the Date#compareTo(Date) method also, but then, you need to interpret the output of the compareTo method accordingly.

As the docs say:

The value 0 if the argument Date is equal to this Date; a value less than 0 if this Date is before the Date argument; and a value greater than 0 if this Date is after the Date argument.

In your case, you are getting -1 because

new SimpleDateFormat("HHH:mm:ss"); is wrong. Should be new SimpleDateFormat("HH:mm:ss");
int compare= sqlTime3.compareTo(Sqldob1); This sqlTime3 has only time in it. The date is the epoch date as you've not mentioned that, and hence, its always going to be before new Date() which is today.

Your solution:- (Hope this addresses your problem)

java.util.Date date1= new java.util.Date();

Time Sqldob1 = new Time(date1.getTime());
System.out.println("User Time: " +Sqldob1);

Calendar cal = Calendar.getInstance();
cal.set(Calendar.HOUR_OF_DAY, 19); // Your hour
cal.set(Calendar.MINUTE, 30); // Your Mintue
cal.set(Calendar.SECOND, 00); // Your second

Time sqlTime3 = new Time(cal.getTime().getTime());
System.out.println("your time: "+sqlTime3);

if(Sqldob1.before(sqlTime3)){
   Sqldob1 = sqlTime3; 
   System.out.println("inside loop");
}

edited Sep 27 '13 at 11:11

answered Sep 27 '13 at 08:31

Rahul

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thnk u plz helping me – user2767354 Sep 27 '13 at 08:40
Look at my answer. I've editing to show a couple of problems in your code and why you're getting `-1` always. – Rahul Sep 27 '13 at 08:42
can u plz explain here am giving only the constant time as sqltime3 it is not comparing properly can u plz assist me – user2767354 Sep 27 '13 at 09:04
SimpleDateFormat ra = new SimpleDateFormat("HH:mm:ss"); – user2767354 Sep 27 '13 at 09:10
@user2767354 - look at the point 2. You've not mentioned any date at all. That's why the epoch date is taken by default. – Rahul Sep 27 '13 at 09:23
can u plz tell me that time wht am comparing is constant time 09:30:00 but the date will vary every day how can mention the date in it than k u – user2767354 Sep 27 '13 at 09:26
hi can plz help me in it – user2767354 Sep 27 '13 at 09:38
What is your ultimate goal? What do you want to achieve with it? You have to tell that, else its really not clear what you want to compare?! – Rahul Sep 27 '13 at 09:40
just i want to compare the sqldob1 that is from user when login with sqltime3 that i have taken that as manually i.e 09:30:00 if sqldob1 is less than 09:30 i want to enter my time as 09:30:00 otherwise i will enter sqldob1 time to database thats it ...thnk u – user2767354 Sep 27 '13 at 09:46
@user2767354 - Look at my edit! I hope it helps you solve this! – Rahul Sep 27 '13 at 09:55
thnk u i will check it – user2767354 Sep 27 '13 at 09:57
hi i'm sorry that above code is also not working can u plz plz check once i will updated my code now thnk u – user2767354 Sep 27 '13 at 10:15
control will not enter inside the loop itself – user2767354 Sep 27 '13 at 10:17
Obviously it won't cuz the current time now is past 9:30. Try to change the 9:30 to 19:30 and then run the code. It'll enter the `if` block. – Rahul Sep 27 '13 at 10:28
here i'm changing my system timings can u plz explain me whts wrong in it – user2767354 Sep 27 '13 at 10:32
Don't change that. Change this static time and check. – Rahul Sep 27 '13 at 10:51
even that also i done it.Can u plz tell me is there any mistakes in my above code thnk u – user2767354 Sep 27 '13 at 10:53

score 3 · Answer 2 · answered Sep 27 '13 at 08:31

3

You need to parse the date and call methods like before(), after() and equals() like this,

if(date.before(date1)){
    System.out.println(" date is before date1 ");
}
if(date.after(date1)){
    System.out.println(" date is after date1 ");
}

If both date and date1 are equal you can use equals method,

if(date.equals(date1)){
    System.out.println(" date and date1 are equal");
}

answered Sep 27 '13 at 08:31

Lucky

16,787
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thnk u for helping me – user2767354 Sep 27 '13 at 08:40
You're welcome..cheers.. if it helped, mark the answer as accepted. (Tick below the vote counter) – Lucky Sep 27 '13 at 08:57

Ole V.V. · Answer 3 · 2017-07-07T03:52:50.250

Modern version:

    LocalDateTime dateTime1 = LocalDateTime.now(ZoneId.systemDefault());
    LocalDate dob = dateTime1.toLocalDate();
    System.out.println("date " + dob);

    LocalTime dob1 = dateTime1.toLocalTime();
    System.out.println("User Time: " + dob1);

    String yourTime = "09:30:00"; 
    LocalTime time3 = LocalTime.parse(yourTime);
    System.out.println("your time " + time3);

    if (dob1.isBefore(time3)) {
        dob1 = time3;
        System.out.println("inside if statement");
    }

When I ran this code this morning, it printed:

date 2017-07-07
User Time: 05:32:01.881
your time 09:30
inside if statement

The point is: With the old and now long outdated classes Date and Time it is easy not to get things right. With the modern classes I use here, it’s much easier to get them right.

Are you using java.sql types because you really need to get your date and time from a database and/or store them into one? This was what these were for, you shouldn’t really have used them for other purposes. I use “was” and “were” intentionally because you don’t need them for this purpose either anymore. With a new JDBC driver, you can get a LocalDateTime from the database and store one back, or depending on your column datatype get an Instant and convert it to LocalDateTime:

    LocalDateTime dateTime2 = instantFromDb.atZone(ZoneId.systemDefault())
            .toLocalDateTime();

PS Item 2. in SoduRahul’s answer gives the real and correct explanation of what went wrong in your program: though Time was meant for time-of-day only, your Sqldob1 ends up holding today’s date and sqlTime3 the date of the epoch (January 1, 1970), so the former will always be after the latter by their before method.

score 0 · Answer 4 · answered Sep 27 '13 at 08:44

0

compareTo() method always return zero for equal and non-zero for unequal dates.

answered Sep 27 '13 at 08:44

Dax Joshi

143
11

comparing the two times is greater or lesser in java

4 Answers4