This article shows Java 8 and legacy date-time APIs example to check if a date is 30 days or 6 months older than the current date. 1. Java 8 isBefore() 2. Java 8 ChronoUnit.{UNIT}.between() 3. Java 8 Period.between() 4. Legacy Calendar and Date 5. References 1. Java 8 isBefore() First minus the current date and […]
A Java example to convert Java 8 java.time.LocalDate and java.time.LocalDateTime back to the classic java.uti.Date. JavaDateExample.java package com.mkyong.time; import java.time.LocalDate; import java.time.LocalDateTime; import java.time.ZoneId; import java.time.ZonedDateTime; import java.util.Date; public class JavaDateExample { public static void main(String[] args) { // LocalDate -> Date LocalDate localDate = LocalDate.of(2020, 2, 20); Date date = Date.from(localDate.atStartOfDay(ZoneId.systemDefault()).toInstant()); // LocalDateTime -> […]
If Java 8, DateTimeFormatter, else SimpleDateFormat to change the date format in a String. 1. DateTimeFormatter (Java 8) Convert the String to LocalDateTime and change the date format with DateTimeFormatter DateFormatExample1.java package com.mkyong; import java.time.LocalDateTime; import java.time.format.DateTimeFormatter; public class DateFormatExample1 { // date format 1 private static final DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.S"); // date […]
A collection of Java date and time examples. 1. Java Date Time APIs In old days, we use the following classic Date and Calendar APIs to represent and manipulate date. java.util.Date – date and time, print with default time-zone. java.util.Calendar – date and time, more methods to manipulate date. java.text.SimpleDateFormat – formatting (date -> text), […]
In Java 8, you can use the predefined java.time.temporal.TemporalAdjusters to adjust a date or Temporal 1. TemporalAdjusters Example to move a date to firstDayOfMonth, firstDayOfNextMonth, next Monday and etc. TestDate.java package com.mkyong.time; import java.time.DayOfWeek; import java.time.LocalDate; import java.time.temporal.TemporalAdjusters; public class TestDate { public static void main(String[] args) { LocalDate localDate = LocalDate.now(); System.out.println("current date : […]
This article shows you how to add days to the current date, using the classic java.util.Calendar and the new Java 8 date and time APIs. 1. Calendar.add Example to add 1 year, 1 month, 1 day, 1 hour, 1 minute and 1 second to the current date. DateExample.java package com.mkyong.time; import java.text.DateFormat; import java.text.SimpleDateFormat; import […]
Few examples to show you how to use Java 8 Duration, Period and ChronoUnit objects to find out the difference between dates. Duration – Measures time in seconds and nanoseconds. Period – Measures time in years, months and days. 1. Duration Example A java.time.Duration example to find out difference seconds between two LocalDateTime DurationExample.java package […]
Few examples to show you how to format java.time.LocalDateTime in Java 8. 1. LocalDateTime + DateTimeFormatter To format a LocalDateTime object, uses DateTimeFormatter TestDate1.java package com.mkyong.time; import java.time.LocalDateTime; import java.time.format.DateTimeFormatter; public class TestDate1 { public static void main(String[] args) { //Get current date time LocalDateTime now = LocalDateTime.now(); System.out.println("Before : " + now); DateTimeFormatter formatter […]
Java 8 examples to show you how to convert from Instant to ZonedDateTime 1. Instant -> ZonedDateTime Example to convert a Instant UTC+0 to a Japan ZonedDateTime UTC+9 InstantZonedDateTime1.java package com.mkyong.date; import java.time.Instant; import java.time.ZoneId; import java.time.ZonedDateTime; public class InstantZonedDateTime1 { public static void main(String[] argv) { // Z = UTC+0 Instant instant = Instant.now(); […]
Java 8 examples to show you how to convert from Instant to LocalDateTime 1. Instant -> LocalDateTime The java.time.LocalDateTime has no concept of time zone, just provide a zero offset UTC+0. InstantExample1.java package com.mkyong.date; import java.time.Instant; import java.time.LocalDateTime; import java.time.ZoneOffset; public class InstantExample1 { public static void main(String[] argv) { // Parse a ISO 8601 […]
Here are a few Java examples of converting a String to the new Java 8 Date API – java.time.LocalDate DateTimeFormatter formatter = DateTimeFormatter.ofPattern("d/MM/yyyy"); String date = "16/08/2016"; //convert String to LocalDate LocalDate localDate = LocalDate.parse(date, formatter); The key is understand the DateTimeFormatter patterns Note You may interest at this classic java.util.Date example – How to […]
In this tutorial, we will show you few examples (ZonedDateTime (Java 8), Date, Calendar and Joda Time) to convert a date and time between different time zones. All examples will be converting the date and time from (UTC+8:00) Asia/Singapore – Singapore Time Date : 22-1-2015 10:15:55 AM to (UTC-5:00) America/New_York – Eastern Standard Time Date […]
This Java example shows you how to display a list of TimeZone with GMT in front. P.S Tested with JDK 1.7 Java 8 You may interest at this example – Display all ZoneId and its UTC offset TimeZoneExample.java package com.mkyong.test; import java.util.TimeZone; import java.util.concurrent.TimeUnit; public class TimeZoneExample { public static void main(String[] args) { String[] […]
In Java, you can use calendar.setTime(date) to convert a Date object to a Calendar object. Calendar calendar = Calendar.getInstance(); Date newDate = calendar.setTime(date); A Full example DateAndCalendar.java import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; public class DateAndCalendar { public static void main(String[] argv) throws ParseException { //1. Create a Date from String SimpleDateFormat sdf […]
This tutorial shows you how to work with java.util.Date and java.util.Calendar. 1. Java Date Examples Few examples to work with Date APIs. Example 1.1 – Convert Date to String. SimpleDateFormat sdf = new SimpleDateFormat("dd/M/yyyy"); String date = sdf.format(new Date()); System.out.println(date); //15/10/2013 Example 1.2 – Convert String to Date. SimpleDateFormat sdf = new SimpleDateFormat("dd-M-yyyy hh:mm:ss"); String […]
Two Java examples show you how to print the elapsed time in days, hours, minutes and seconds format. 1. Standard JDK Date APIs You need to calculate the elapsed time manually. DateTimeUtils.java package com.mkyong.dateUtils; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class DateTimeUtils { public static void main(String[] args) { DateTimeUtils obj = new DateTimeUtils(); […]
In this tutorial, we will show you how to convert a String to java.util.Date. Many Java beginners are stuck in the Date conversion, hope this summary guide will helps you in some ways. // String -> Date SimpleDateFormat.parse(String); // Date -> String SimpleDateFormat.format(date); Refer to table below for some of the common date and time […]
In this tutorial, we show you 2 examples to calculate date / time difference in Java : Manual time calculation. Joda time library. 1. Manual time calculation Converts Date in milliseconds (ms) and calculate the differences between two dates, with following rules : 1000 milliseconds = 1 second 60 seconds = 1 minute 60 minutes […]
A Java example to check if a provided date is within a range of 3 momths before and after current date. The idea is quite simple, just use Calendar class to roll the month back and forward to create a “date range”, and use the Date.before() and Date.after() to check if the Date is within […]
This article shows how to use the Java 8 DateTimeFormatter to check if a date format is valid in Java. Below are the requirements for a valid date. Year format, 1900, 2099 Month format, 1, 01, 2, 02… 12 Day format, 1, 01… 31 Leap year, February 29 days. Common year, February 28 days. Month […]
In Android, you can use “android.widget.DatePicker” class to render a date picker component to select day, month and year in a pre-defined user interface. In this tutorial, we show you how to render date picker component in current page via android.widget.DatePicker, and also in dialog box via android.app.DatePickerDialog. In addition, we also show you how […]
Problem A simple table script in Oracle database. CREATE TABLE DBUSER ( USER_ID NUMBER (5) NOT NULL, USERNAME VARCHAR2 (20) NOT NULL, CREATED_BY VARCHAR2 (20) NOT NULL, CREATED_DATE DATE NOT NULL, PRIMARY KEY ( USER_ID ) ) No idea how to insert current date value, e.g. “04/04/2011” into “CREATED_DATE” field, via JDBC PreparedStatement. String insertTableSQL […]
f:convertDateTime” is a standard JSF converter tag, which converts String into a specified “Date” format. In addition, it’s used to implement the date validation as well. The following JSF 2.0 example shows you how to use this “f:convertDateTime” tag. 1. Managed Bean A simple managed bean, with a “date” property. package com.mkyong; import java.io.Serializable; import […]
Spring example to show you how to inject a “Date” into bean property. package com.mkyong.common; import java.util.Date; public class Customer { Date date; public Date getDate() { return date; } public void setDate(Date date) { this.date = date; } @Override public String toString() { return "Customer [date=" + date + "]"; } } Bean configuration […]
This article shows how to get the current date time or timestamps in Java. import java.sql.Timestamp; import java.time.Instant; import java.util.Date; // 2025-03-07 21:34:46.504 // Get current java.sql.Timestamp Timestamp timestamp = new Timestamp(System.currentTimeMillis()); // 2025-03-07 21:34:46.504 // Get current java.sql.Timestamp from a Date Date date = new Date(); Timestamp timestamp2 = new Timestamp(date.getTime()); // convert Instant […]
This article shows few examples to compare two dates in Java. Updated with Java 8 examples. 1. Compare two date 1.1 Date.compareTo 1.2 Date.before(), Date.after() and Date.equals() 1.3 Check if a date is within a certain range 2. Compare two calendar 3. Compare two date and time (Java 8) 3.1 Compare two LocalDate 3.2 Compare […]
In this tutorial, we will show you how to get the current date time from the new Java 8 java.time.* like Localdate, LocalTime, LocalDateTime, ZonedDateTime, Instant and also the legacy date time APIs like Date and Calendar. Table of contents 1. Get current date time in Java 2. java.time.LocalDate 3. java.time.LocalTime 4. java.time.LocalDateTime 5. java.time.ZonedDateTime […]
This article shows how to use regex + code to validate a date format, support single and leading zero month and day format (1 or 01), check for the 30 or 31 days of the month, and leap year validation. Below are the requirements for a valid date. Year format, 1900, 2099 regex Month format, […]
In Java, you can use the following ways to measure elapsed time in Java. 1. System.nanoTime() This is the recommended solution to measure elapsed time in Java. ExecutionTime1.java package com.mkyong.time; import java.util.concurrent.TimeUnit; public class ExecutionTime1 { public static void main(String[] args) throws InterruptedException { //start long lStartTime = System.nanoTime(); //task calculation(); //end long lEndTime = […]
Java Calendar class (java.util.Calendar) is a very useful and handy class in java date time manipulation. here i will demonstrate how to modify date time with calender class. Get current date time with Calendar() DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"); Calendar cal = Calendar.getInstance(); System.out.println("Current Date Time : " + dateFormat.format(cal.getTime())); Calender date time manipulation […]
