תאריך Java 8 – LocalDate, LocalDateTime, Instant

package com.journaldev.java8.time;

import java.time.LocalDate;
import java.time.Month;
import java.time.ZoneId;

/**
 * LocalDate דוגמאות
 * @author pankaj
 *
 */
public class LocalDateExample {

	public static void main(String[] args) {
		
		//תאריך נוכחי
		LocalDate today = LocalDate.now();
		System.out.println("Current Date="+today);
		
		//יצירת LocalDate על ידי הזנת ארגומנטים קלט
		LocalDate firstDay_2014 = LocalDate.of(2014, Month.JANUARY, 1);
		System.out.println("Specific Date="+firstDay_2014);
		
		
		//נסו ליצור תאריך על ידי הזנת קלטים לא חוקיים
		//LocalDate feb29_2014 = LocalDate.of(2014, Month.FEBRUARY, 29);
		//חריגה בניתוח של "main" java.time.DateTimeException: 
		//תאריך לא חוקי '29 בפברואר' מאחר ו-'2014' אינו שנה מעוברת
		
		//התאריך הנוכחי ב"Asia/Kolkata", ניתן לקבל אותו מתיעוד ה-ZoneId
		LocalDate todayKolkata = LocalDate.now(ZoneId.of("Asia/Kolkata"));
		System.out.println("Current Date in IST="+todayKolkata);

		//java.time.zone.ZoneRulesException: מזהה אזור זמן לא ידוע: IST
		//LocalDate todayIST = LocalDate.now(ZoneId.of("IST"));
		
		//קבלת תאריך מהתאריך הבסיסי כלומר 01/01/1970
		LocalDate dateFromBase = LocalDate.ofEpochDay(365);
		System.out.println("365th day from base date= "+dateFromBase);
		
		LocalDate hundredDay2014 = LocalDate.ofYearDay(2014, 100);
		System.out.println("100th day of 2014="+hundredDay2014);
	}

}

Current Date=2014-04-28
Specific Date=2014-01-01
Current Date in IST=2014-04-29
365th day from base date= 1971-01-01
100th day of 2014=2014-04-10

package com.journaldev.java8.time;

import java.time.LocalTime;
import java.time.ZoneId;

/**
 * LocalTime Examples
 * @author pankaj
 *
 */
public class LocalTimeExample {

	public static void main(String[] args) {
		
		//הזמן הנוכחי
		LocalTime time = LocalTime.now();
		System.out.println("Current Time="+time);
		
		//יצירת LocalTime על ידי מסירת ארגומנטים כקלט
		LocalTime specificTime = LocalTime.of(12,20,25,40);
		System.out.println("Specific Time of Day="+specificTime);
		
		
		//נסו ליצור זמן על ידי מסירת קלטים לא חוקיים
		//LocalTime invalidTime = LocalTime.of(25,20);
		//Exception in thread "main" java.time.DateTimeException: 
		//ערך לא חוקי עבור שעתי היום (ערכים חוקיים 0 - 23): 25
		
		//תאריך הנוכחי באזור זמן "Asia/Kolkata", ניתן לקבל אותו מתיעוד ה־ZoneId
		LocalTime timeKolkata = LocalTime.now(ZoneId.of("Asia/Kolkata"));
		System.out.println("Current Time in IST="+timeKolkata);

		//java.time.zone.ZoneRulesException: Unknown time-zone ID: IST
		//LocalTime todayIST = LocalTime.now(ZoneId.of("IST"));
		
		//משיכת תאריך מהתאריך הבסיסי, כלומר 01/01/1970
		LocalTime specificSecondTime = LocalTime.ofSecondOfDay(10000);
		System.out.println("10000th second time= "+specificSecondTime);

	}

}

Current Time=15:51:45.240
Specific Time of Day=12:20:25.000000040
Current Time in IST=04:21:45.276
10000th second time= 02:46:40

package com.journaldev.java8.time;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.Month;
import java.time.ZoneId;
import java.time.ZoneOffset;

public class LocalDateTimeExample {

	public static void main(String[] args) {
		
		//תאריך נוכחי
		LocalDateTime today = LocalDateTime.now();
		System.out.println("Current DateTime="+today);
		
		//תאריך נוכחי באמצעות LocalDate ו־LocalTime
		today = LocalDateTime.of(LocalDate.now(), LocalTime.now());
		System.out.println("Current DateTime="+today);
		
		//יצירת LocalDateTime על ידי מתן ארגומנטים קלט
		LocalDateTime specificDate = LocalDateTime.of(2014, Month.JANUARY, 1, 10, 10, 30);
		System.out.println("Specific Date="+specificDate);
		
		
		//נסו ליצור תאריך על ידי מתן קלטים לא חוקיים
		//LocalDateTime feb29_2014 = LocalDateTime.of(2014, Month.FEBRUARY, 28, 25,1,1);
		//Exception in thread "main" java.time.DateTimeException: 
		//ערך לא חוקי עבור שעת היום (ערכים חוקיים 0 - 23): 25

		
		//תאריך נוכחי ב"Asia/Kolkata", ניתן לקבל אותו מתיעוד ה־ZoneId
		LocalDateTime todayKolkata = LocalDateTime.now(ZoneId.of("Asia/Kolkata"));
		System.out.println("Current Date in IST="+todayKolkata);

		//java.time.zone.ZoneRulesException: Unknown time-zone ID: IST
		//LocalDateTime todayIST = LocalDateTime.now(ZoneId.of("IST"));
		
		//קבלת תאריך מתאריך הבסיס, כלומר 01/01/1970
		LocalDateTime dateFromBase = LocalDateTime.ofEpochSecond(10000, 0, ZoneOffset.UTC);
		System.out.println("10000th second time from 01/01/1970= "+dateFromBase);

	}

}

Current DateTime=2014-04-28T16:00:49.455
Current DateTime=2014-04-28T16:00:49.493
Specific Date=2014-01-01T10:10:30
Current Date in IST=2014-04-29T04:30:49.493
10000th second time from 01/01/1970= 1970-01-01T02:46:40

package com.journaldev.java8.time;

import java.time.Duration;
import java.time.Instant;

public class InstantExample {

	public static void main(String[] args) {
		// חותמת זמן נוכחית
		Instant timestamp = Instant.now();
		System.out.println("Current Timestamp = "+timestamp);
		
		// Instant מתוך חותמת זמן
		Instant specificTime = Instant.ofEpochMilli(timestamp.toEpochMilli());
		System.out.println("Specific Time = "+specificTime);
		
		// דוגמה ל-Duration
		Duration thirtyDay = Duration.ofDays(30);
		System.out.println(thirtyDay);
	}

}

Current Timestamp = 2014-04-28T23:20:08.489Z
Specific Time = 2014-04-28T23:20:08.489Z
PT720H

package com.journaldev.java8.time;

import java.time.LocalDate;
import java.time.LocalTime;
import java.time.Period;
import java.time.temporal.TemporalAdjusters;

public class DateAPIUtilities {

	public static void main(String[] args) {
		
		LocalDate today = LocalDate.now();
		
		//קבל את השנה, בדוק אם זו שנה מעוברת
		System.out.println("Year "+today.getYear()+" is Leap Year? "+today.isLeapYear());
		
		//השווה בין שני LocalDate לפני ואחרי
		System.out.println("Today is before 01/01/2015? "+today.isBefore(LocalDate.of(2015,1,1)));
		
		//צור LocalDateTime מתוך LocalDate
		System.out.println("Current Time="+today.atTime(LocalTime.now()));
		
		//פעולות חיבור וחיסור
		System.out.println("10 days after today will be "+today.plusDays(10));
		System.out.println("3 weeks after today will be "+today.plusWeeks(3));
		System.out.println("20 months after today will be "+today.plusMonths(20));

		System.out.println("10 days before today will be "+today.minusDays(10));
		System.out.println("3 weeks before today will be "+today.minusWeeks(3));
		System.out.println("20 months before today will be "+today.minusMonths(20));
		
		//תוקנים זמניים להתאמת התאריכים
		System.out.println("First date of this month= "+today.with(TemporalAdjusters.firstDayOfMonth()));
		LocalDate lastDayOfYear = today.with(TemporalAdjusters.lastDayOfYear());
		System.out.println("Last date of this year= "+lastDayOfYear);
		
		Period period = today.until(lastDayOfYear);
		System.out.println("Period Format= "+period);
		System.out.println("Months remaining in the year= "+period.getMonths());		
	}
}

Year 2014 is Leap Year? false
Today is before 01/01/2015? true
Current Time=2014-04-28T16:23:53.154
10 days after today will be 2014-05-08
3 weeks after today will be 2014-05-19
20 months after today will be 2015-12-28
10 days before today will be 2014-04-18
3 weeks before today will be 2014-04-07
20 months before today will be 2012-08-28
First date of this month= 2014-04-01
Last date of this year= 2014-12-31
Period Format= P8M3D
Months remaining in the year= 8

package com.journaldev.java8.time;

import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class DateParseFormatExample {

	public static void main(String[] args) {
		
		//דוגמאות לפורמט
		LocalDate date = LocalDate.now();
		//פורמט ברירת מחדל
		System.out.println("Default format of LocalDate="+date);
		//פורמט מסוים
		System.out.println(date.format(DateTimeFormatter.ofPattern("d::MMM::uuuu")));
		System.out.println(date.format(DateTimeFormatter.BASIC_ISO_DATE));
		
		
		LocalDateTime dateTime = LocalDateTime.now();
		//פורמט ברירת מחדל
		System.out.println("Default format of LocalDateTime="+dateTime);
		//פורמט מסוים
		System.out.println(dateTime.format(DateTimeFormatter.ofPattern("d::MMM::uuuu HH::mm::ss")));
		System.out.println(dateTime.format(DateTimeFormatter.BASIC_ISO_DATE));
		
		Instant timestamp = Instant.now();
		//פורמט ברירת מחדל
		System.out.println("Default format of Instant="+timestamp);
		
		//דוגמאות לניתוח
		LocalDateTime dt = LocalDateTime.parse("27::Apr::2014 21::39::48",
				DateTimeFormatter.ofPattern("d::MMM::uuuu HH::mm::ss"));
		System.out.println("Default format after parsing = "+dt);
	}

}

Default format of LocalDate=2014-04-28
28::Apr::2014
20140428
Default format of LocalDateTime=2014-04-28T16:25:49.341
28::Apr::2014 16::25::49
20140428
Default format of Instant=2014-04-28T23:25:49.342Z
Default format after parsing = 2014-04-27T21:39:48

package com.journaldev.java8.time;

import java.time.Instant;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.TimeZone;

public class DateAPILegacySupport {

	public static void main(String[] args) {
		
		//תאריך ל־Instant
		Instant timestamp = new Date().toInstant();
		//כעת ניתן להמיר את Instant ל־LocalDateTime או לכיתות דומות אחרות
		LocalDateTime date = LocalDateTime.ofInstant(timestamp, 
						ZoneId.of(ZoneId.SHORT_IDS.get("PST")));
		System.out.println("Date = "+date);
		
		//לוח שנה ל־Instant
		Instant time = Calendar.getInstance().toInstant();
		System.out.println(time);
		//אזור זמן ל־ZoneId
		ZoneId defaultZone = TimeZone.getDefault().toZoneId();
		System.out.println(defaultZone);
		
		//ZonedDateTime מלוח שנה ספציפי
		ZonedDateTime gregorianCalendarDateTime = new GregorianCalendar().toZonedDateTime();
		System.out.println(gregorianCalendarDateTime);
		
		//API של תאריך לכיתות התאריך/הזמן הישנות
		Date dt = Date.from(Instant.now());
		System.out.println(dt);
		
		TimeZone tz = TimeZone.getTimeZone(defaultZone);
		System.out.println(tz);
		
		GregorianCalendar gc = GregorianCalendar.from(gregorianCalendarDateTime);
		System.out.println(gc);
		
	}

}

Date = 2014-04-28T16:28:54.340
2014-04-28T23:28:54.395Z
America/Los_Angeles
2014-04-28T16:28:54.404-07:00[America/Los_Angeles]
Mon Apr 28 16:28:54 PDT 2014
sun.util.calendar.ZoneInfo[id="America/Los_Angeles",offset=-28800000,dstSavings=3600000,useDaylight=true,transitions=185,lastRule=java.util.SimpleTimeZone[id=America/Los_Angeles,offset=-28800000,dstSavings=3600000,useDaylight=true,startYear=0,startMode=3,startMonth=2,startDay=8,startDayOfWeek=1,startTime=7200000,startTimeMode=0,endMode=3,endMonth=10,endDay=1,endDayOfWeek=1,endTime=7200000,endTimeMode=0]]
java.util.GregorianCalendar[time=1398727734404,areFieldsSet=true,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="America/Los_Angeles",offset=-28800000,dstSavings=3600000,useDaylight=true,transitions=185,lastRule=java.util.SimpleTimeZone[id=America/Los_Angeles,offset=-28800000,dstSavings=3600000,useDaylight=true,startYear=0,startMode=3,startMonth=2,startDay=8,startDayOfWeek=1,startTime=7200000,startTimeMode=0,endMode=3,endMonth=10,endDay=1,endDayOfWeek=1,endTime=7200000,endTimeMode=0]],firstDayOfWeek=2,minimalDaysInFirstWeek=4,ERA=1,YEAR=2014,MONTH=3,WEEK_OF_YEAR=18,WEEK_OF_MONTH=5,DAY_OF_MONTH=28,DAY_OF_YEAR=118,DAY_OF_WEEK=2,DAY_OF_WEEK_IN_MONTH=4,AM_PM=1,HOUR=4,HOUR_OF_DAY=16,MINUTE=28,SECOND=54,MILLISECOND=404,ZONE_OFFSET=-28800000,DST_OFFSET=3600000]