🌀 Java Day Of Year

2. D in a SimpleDateFormat pattern is the day of the year, not days since The Epoch. The simplest thing is probably to multiply by the number of milliseconds in a day (86400000 = 24 * 60 * 60 * 1000) and use new Date (milliseconds): long days = 17749; Date d = new Date (days * 86400000L); The old java.util.Date is a failed API, though. 5. You might try my lib Time4J which offers a Jewish/Hebrew calendar and use following code: HebrewCalendar hebcal = HebrewCalendar.nowInSystemTime (); int weekOfYear = hebcal.getInt (HebrewCalendar.WEEK_OF_YEAR); It uses the default week model/definition in Israel which starts the week on Sunday (after Sabbat). Get start date of that quarter (as seen in code below, passing year & month & dayOfMonth to constructor). stopDateOfPreviousQuarter( someDate ) Call "startDateOfQuarter" method, passing the date in question. On the start date returned, call the Joda-Time method minusDays(1). Voilà, you have the date of the last day in the previous quarter. /** * Obtains an instance of {@code LocalDate} from a year and day-of-year. *

* The day-of-year must be valid for the year, otherwise an exception will be thrown. * * @param year the year to represent, from MIN_YEAR to MAX_YEAR * @param dayOfYear the day-of-year to represent, from 1 to 366 * @return the local date, not null * @throws A date without a time-zone in the ISO-8601 calendar system, such as 2007-12-03. LocalDate is an immutable date-time object that represents a date, often viewed as year-month-day. Other date fields, such as day-of-year, day-of-week and week-of-year, can also be accessed. For example, the value "2nd October 2007" can be stored in a LocalDate. We’re using Date.prototype.getFullYear() and Date() to the get the first day of the year and subtract one from another and divide by the milliseconds in a day. Finally, we’re using Math.floor() to round the result and print it as an integer. function dayOfTheYear(date) { return Math.floor((date - new Date(date.getFullYear(), 0, 0)) / 1000 Now, let’s take the simple Date Time API which converts the String value to Date value using SimpleDateFormat: Java introduced a new Date Time API call with its version 8 to represent the Date time parameters known as “java.time”. The old call in all the previous versions to represent the date was java.util.date. In this I get leap & ordinary year and month, but I don't know how to get day of the given date month year. And also having one question: 1800 and 1900 are ordinary year but I get these years Years age = Years.yearsBetween (birthDate, currentDate); return age.getYears (); } 4. Using Java 7. Without a dedicated API in Java 7, we are left to roll our own, and so there are quite a few approaches. public int calculateAgeWithJava7( Date birthDate, Date currentDate) { // validate inputs In our case, this is 08. Divide it by 4 and discard any remainder. 08 / 4 = 02. Add the day of the month. In our example, 02 + 01 = 03. The month in our example is January, which has the key value of 1. Therefore, 03 + 01 = 04. Since the date is in January of a leap year, subtract 1 from step 4 i.e. 04 – 01 = 03. dr [0] = c.getTime (); line you will get time for SUNDAY because you set it and the date then returns 23.3. Principal is the same for the end of week: On the line. c.set (day, c.getActualMaximum (day)); you set "DAY_OF_WEEK" to SATURDAY and then it will return you date 22.3. //EDIT2: method for calculating start and end of week. Create and array that contains the numbers of days for each month: int [] daysInMonth=new int [13]; int [1]=31; // January (month 1) has 31 days int [2]=28; // or 29 if it's a leap year. And so on. Note that I created an array with 13 positions but I'm ignoring position 0 just to make January as month 1 instead of 0. Then you do a loop like that: 26dS.

java day of year