This question already has answers here:
how to add days to java simple date format
(2 answers)
Closed 8 years ago.
I need to increment date by some days.
private Date now = new Date();
private Date result;
public void incrementDate(Integer days) {
result =
}
So if days equals 3 i need to increment my now date on 3 days and set it to result.
I know that java 8 has plusDays method in LocalDate class. Is there a way how to implement this in java 7.
Use Calendar
Calendar cal = Calendar.getInstance ();
cal.setTime (now);
cal.add (Calendar.DATE, days);
plus other fun stuff.
Use Calendar to do this:
Calendar cal = new GregorianCalendar();
cal.add(Calendar.DATE,3);
result = cal.getTime()
I suggest you make the function static and pass in now. return Date and use a Calendar. Something like,
public static Date incrementDate(Date now, int days) {
Calendar cal = Calendar.getInstance();
cal.setTime(now);
cal.add(Calendar.DAY_OF_MONTH, days);
return cal.getTime();
}
And then to test it
public static void main(String[] args) {
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
Date now = new Date();
System.out.println(df.format(now));
System.out.println(df.format(incrementDate(now, 3)));
}
Output here (today) is
2014-11-12
2014-11-15
try this code :
SimpleDateFormat sdf=new SimpleDateFormat("yyyy/MM/dd");
Calendar cal=Calendar.getInstance();
String today=sdf.format(cal.getTime());
System.out.println(today);
cal.add(Calendar.DATE, 20);
String After=sdf.format(cal.getTime());
System.out.println(After);
Date now = new Date();
Related
This question already has answers here:
Calendar date to yyyy-MM-dd format in java
(11 answers)
Closed 4 years ago.
I am encountering an issue which is related to Java Date Function.
I'm getting the date from Application (example: 6/5/18) which is in MM/DD/YY format. Now I need to do -2 from the date. I know how to do -2 from current system date using calendar object (see the below code).
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE,-2);
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yy");
String PastDate = dateFormat.format(cal.getTime());
info("Date is displayed as : "+ PastDate );
I'm not able to put the date which I'm getting from Application in this format. Can someone please help me? (Any other way to do it would also be fine)
I suggest you to use Java 8 compatible Date and Time types.
If you use java.time.LocalDate then this is the solution:
LocalDate.now().minusDays(2)
From your question, it seems that you have the challenge in dealing with formatting, and then doing the subtraction.
I would recommend Java Date and Time Apis for this purpose, using a formatter.
A junit method to achieve your requirement is given below
#Test
public void testDateFormatUsingJava8() {
CharSequence inputdateTxt = "6/5/18";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("M/d/yy");
LocalDate inputDate = LocalDate.parse(inputdateTxt, formatter);
System.out.println(inputDate.minusDays(2L).format(formatter));
}
#Test
public void testDateCalenderUsingStringSplit() {
String inputdateTxt = "6/5/18";
String[] dateComponenets = inputdateTxt.split("//");
Calendar cal = Calendar.getInstance();
//Know where are the year month and date are stored.
cal.set(Integer.parseInt(dateComponenets[2]), Integer.parseInt(dateComponenets[0]), Integer.parseInt(dateComponenets[2]) );
cal.add(Calendar.DATE,-2);
DateFormat dateFormat = new SimpleDateFormat("M/d/yy");
String pastDate = dateFormat.format(cal.getTime());
System.out.println("Date is displayed as : "+ pastDate );
}
#Test
public void testDateCalenderUsingJavaUtilDateApi() throws ParseException {
String inputdateTxt = "6/5/18";
DateFormat dateFormat = new SimpleDateFormat("M/d/yy");
Date date = dateFormat.parse(inputdateTxt);
Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.add(Calendar.DATE,-2);
String pastDate = dateFormat.format(cal.getTime());
System.out.println("Date is displayed as : "+ pastDate );
The reason why I use "M/d/yy" is because your question does not pad the date and month fields in the input date with a zero. If there is a guarantee that you receive a padded value in the date and month field, using "MM/dd/yy" is suggested.
See the following answer for your reference :
DateTimeFormatterSupport for Single Digit Values
EDIT: considering the limitation to not use Java 8 Date Time APIs, I have added two other alternatives to solve the problem. The OP is free to choose any one of the solutions. Kept the Java 8 solution intact for information purposes.
Calendar cal = Calendar.getInstance();
cal.set(2018, 5, 6); // add this, setting data from the value you parsed
cal.add(Calendar.DATE,-2);
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yy");
String PastDate = dateFormat.format(cal.getTime());
System.out.println("Date is displayed as : "+ PastDate);
This question already has answers here:
Adding n hours to a date in Java?
(16 answers)
Closed 5 years ago.
I got Codes below, it generates my current time.
public static void main(String[] args) {
long timeInMillis = System.currentTimeMillis();
Calendar cal1 = Calendar.getInstance();
cal1.setTimeInMillis(timeInMillis);
SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm:ss a");
String dateforrow = dateFormat.format(cal1.getTime());
System.out.println(dateforrow );
}
Now How can I add hours to the current time? Like for example my current time 4:30:00 PM , and I want to add 8 hours to it, so maybe the output is 0:30:00 AM. I have no Idea.
You can try something like,
public static void main(String[] args) {
long timeInMillis = System.currentTimeMillis();
Calendar cal1 = Calendar.getInstance();
cal1.setTimeInMillis(timeInMillis);
cal1.add(Calendar.HOUR, 8);
SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm:ss a");
String dateforrow = dateFormat.format(cal1.getTime());
System.out.println(dateforrow );
}
long timeInMillis = System.currentTimeMillis();
Calendar cal1 = Calendar.getInstance();
cal1.setTimeInMillis(timeInMillis);
Date date = cal1.getTime();
//add two hour
date.setHours(date.getHours()+2);
cal1.setTime(date);
SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm:ss a");
String dateforrow = dateFormat.format(cal1.getTime());
System.out.println(dateforrow );
add two hour
I try to use current date in date formats but when I use different date formats this makes different results..at first I used this code:
private String getTodayDateString() {
Calendar cal = Calendar.getInstance();
int month=cal.get(Calendar.MONTH);
return Integer.toString(month);
}
and this return me 5 for result for month.
but when I use this code:
private String getTodayDateString2() {
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
return dateFormat.format(cal.getTime());
}
function returns me 14/6/2016 and this means month is calculated 6 in this dateformat.why?where is the problem?
months in calender starts from 0
0 =january
11=december
if you see the source code of Calendar class you will find public final static int JANUARY = 0;
similarily for december public final static int DECEMBER = 11;
Check the source code here
I want to do something like:
Date date = new Date(); // current date
date = date - 300; // substract 300 days from current date and I want to use this "date"
How to do it?
Java 8 and later
With Java 8's date time API change, Use LocalDate
LocalDate date = LocalDate.now().minusDays(300);
Similarly you can have
LocalDate date = someLocalDateInstance.minusDays(300);
Refer to https://stackoverflow.com/a/23885950/260990 for translation between java.util.Date <--> java.time.LocalDateTime
Date in = new Date();
LocalDateTime ldt = LocalDateTime.ofInstant(in.toInstant(), ZoneId.systemDefault());
Date out = Date.from(ldt.atZone(ZoneId.systemDefault()).toInstant());
Java 7 and earlier
Use Calendar's add() method
Calendar cal = Calendar.getInstance();
cal.setTime(dateInstance);
cal.add(Calendar.DATE, -30);
Date dateBefore30Days = cal.getTime();
#JigarJoshi it's the good answer, and of course also #Tim recommendation to use .joda-time.
I only want to add more possibilities to subtract days from a java.util.Date.
Apache-commons
One possibility is to use apache-commons-lang. You can do it using DateUtils as follows:
Date dateBefore30Days = DateUtils.addDays(new Date(),-30);
Of course add the commons-lang dependency to do only date subtract it's probably not a good options, however if you're already using commons-lang it's a good choice. There is also convenient methods to addYears,addMonths,addWeeks and so on, take a look at the api here.
Java 8
Another possibility is to take advantage of new LocalDate from Java 8 using minusDays(long days) method:
LocalDate dateBefore30Days = LocalDate.now(ZoneId.of("Europe/Paris")).minusDays(30);
Simply use this to get date before 300 days, replace 300 with your days:
Date date = new Date(); // Or where ever you get it from
Date daysAgo = new DateTime(date).minusDays(300).toDate();
Here,
DateTime is org.joda.time.DateTime;
Date is java.util.Date
Java 8 Time API:
Instant now = Instant.now(); //current date
Instant before = now.minus(Duration.ofDays(300));
Date dateBefore = Date.from(before);
As you can see HERE there is a lot of manipulation you can do. Here an example showing what you could do!
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
//Add one day to current date.
cal.add(Calendar.DATE, 1);
System.out.println(dateFormat.format(cal.getTime()));
//Substract one day to current date.
cal = Calendar.getInstance();
cal.add(Calendar.DATE, -1);
System.out.println(dateFormat.format(cal.getTime()));
/* Can be Calendar.DATE or
* Calendar.MONTH, Calendar.YEAR, Calendar.HOUR, Calendar.SECOND
*/
With Java 8 it's really simple now:
LocalDate date = LocalDate.now().minusDays(300);
A great guide to the new api can be found here.
In Java 8 you can do this:
Instant inst = Instant.parse("2018-12-30T19:34:50.63Z");
// subtract 10 Days to Instant
Instant value = inst.minus(Period.ofDays(10));
// print result
System.out.println("Instant after subtracting Days: " + value);
I have created a function to make the task easier.
For 7 days after dateString: dateCalculate(dateString,"yyyy-MM-dd",7);
To get 7 days upto dateString: dateCalculate(dateString,"yyyy-MM-dd",-7);
public static String dateCalculate(String dateString, String dateFormat, int days) {
Calendar cal = Calendar.getInstance();
SimpleDateFormat s = new SimpleDateFormat(dateFormat);
try {
cal.setTime(s.parse(dateString));
} catch (ParseException e) {
e.printStackTrace();
}
cal.add(Calendar.DATE, days);
return s.format(cal.getTime());
}
You may also be able to use the Duration class. E.g.
Date currentDate = new Date();
Date oneDayFromCurrentDate = new Date(currentDate.getTime() - Duration.ofDays(1).toMillis());
You can easily subtract with calendar with SimpleDateFormat
public static String subtractDate(String time,int subtractDay) throws ParseException {
Calendar cal = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm", Locale.ENGLISH);
cal.setTime(sdf.parse(time));
cal.add(Calendar.DATE,-subtractDay);
String wantedDate = sdf.format(cal.getTime());
Log.d("tag",wantedDate);
return wantedDate;
}
This question already has answers here:
How to check if a date Object equals yesterday?
(9 answers)
Closed 8 years ago.
The following function produces today's date; how can I make it produce only yesterday's date?
private String toDate() {
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date date = new Date();
return dateFormat.format(date).toString();
}
This is the output:
2012-07-10
I only need yesterday's date like below. Is it possible to do this in my function?
2012-07-09
Update
There has been recent improvements in datetime API with JSR-310.
Instant now = Instant.now();
Instant yesterday = now.minus(1, ChronoUnit.DAYS);
System.out.println(now);
System.out.println(yesterday);
https://ideone.com/91M1eU
Outdated answer
You are subtracting the wrong number:
Use Calendar instead:
private Date yesterday() {
final Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, -1);
return cal.getTime();
}
Then, modify your method to the following:
private String getYesterdayDateString() {
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
return dateFormat.format(yesterday());
}
See
IDEOne Demo
You can do following:
private Date getMeYesterday(){
return new Date(System.currentTimeMillis()-24*60*60*1000);
}
Note: if you want further backward date multiply number of day with 24*60*60*1000 for example:
private Date getPreviousWeekDate(){
return new Date(System.currentTimeMillis()-7*24*60*60*1000);
}
Similarly, you can get future date by adding the value to System.currentTimeMillis(), for example:
private Date getMeTomorrow(){
return new Date(System.currentTimeMillis()+24*60*60*1000);
}
Calendar cal = Calendar.getInstance();
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
System.out.println("Today's date is "+dateFormat.format(cal.getTime()));
cal.add(Calendar.DATE, -1);
System.out.println("Yesterday's date was "+dateFormat.format(cal.getTime()));
Use Calender Api
Try this one:
private String toDate() {
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
// Create a calendar object with today date. Calendar is in java.util pakage.
Calendar calendar = Calendar.getInstance();
// Move calendar to yesterday
calendar.add(Calendar.DATE, -1);
// Get current date of calendar which point to the yesterday now
Date yesterday = calendar.getTime();
return dateFormat.format(yesterday).toString();
}
Try this;
public String toDate() {
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, -1);
return dateFormat.format(cal.getTime());
}
changed from your code :
private String toDate(long timestamp) {
Date date = new Date (timestamp * 1000 - 24 * 60 * 60 * 1000);
return new SimpleDateFormat("yyyy-MM-dd").format(date).toString();
}
but you do better using calendar.
There is no direct function to get yesterday's date.
To get yesterday's date, you need to use Calendar by subtracting -1.
Calendar cal = Calendar.getInstance();
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
System.out.println("Today's date is "+dateFormat.format(cal.getTime()));
cal.add(Calendar.DATE, -1);
System.out.println("Yesterday's date was "+dateFormat.format(cal.getTime()));