In this article, I'll demo y'all how to acquire the electrical current day, month, year, in addition to dayOfWeek inward Java 8 in addition to before version e.g. Java vi in addition to JDK 1.7. Prior to Java 8, y'all tin utilization the Calendar course of written report to acquire the diverse attribute from java.util.Date inward Java. The Calendar course of written report provides a get() method which accepts an integer plain corresponding to the attribute y'all desire to extract in addition to render the value of the plain from given Date, every bit shown here. You powerfulness hold out wondering, why non utilization the getMonth() in addition to getYear() method of java.util.Date itself, well, they are deprecated in addition to tin hold out removed inward the hereafter version, so it is non advised to utilization them. The substitution yell for is, using onetime Date in addition to Calendar API is non easy, it's real hard to argue in addition to debug code written using Calendar API, every bit it uses integer value instead of Enum or String. So, when y'all impress e.g. Month, it volition impress 0 (Zero which may await wrong, only it's the value for Jan inward onetime Date in addition to Calendar API.
Things are much improve inward Java 8, every bit it introduces new Date in addition to Time API. Here y'all tin utilization the LocalDate course of written report from java.time bundle to stand upwards for a date. This course of written report too has several acquire methods to recall dissimilar engagement related attribute e.g. getDayOfWeek() volition render Day of the week, getMonth() volition render Month, in addition to getYear() volition render year. The skillful affair most Java 8 Date API is that y'all don't ask to utilization whatever additional course of written report similar Calendar to extract engagement fields e.g. calendar month in addition to year.
Another skillful affair most java.time API is that it uses Enum for Month in addition to DayOfWeek, which agency a to a greater extent than meaningful in addition to right value is printed when y'all overstep the output to System.out.println() or log into your log file. Don't underestimate the value of this characteristic because it makes debugging quite easy.
You don't ask to guess if five is May or June inward a huge log file spell searching for a missing order. This is too the argue why Joshua Bloch advised to "use Enum over int pattern" to stand upwards for fixed divulge of things inward his all fourth dimension classic majority Effective Java. It makes the output to a greater extent than readable in addition to debugging easier.
Once y'all acquire that, y'all ask to laid the Date to Calendar yesteryear calling setTime() method. It's 1 of the common mistakes inward Java to forget setting Date to Calendar, which leads to wrong output in addition to subtle bugs. There is no compile fourth dimension error because yesteryear default Calendar is laid to the current date inward Java.
Once y'all got a Calendar instance, y'all tin extract whatever engagement related or time-related plain yesteryear using get() method, which takes an int value, denoting the constant defined inward Calendar for that plain e.g. Month, Year, or DayOfWeek every bit shown inward the next example:
You tin come across that this method render an int value which is non real meaningful except the Year part. Thankfully, Calendar corrected 1 error of java.util.Date course of written report which returns engagement from 1900 only residuum of them is withal similar to java.util.Date in addition to hard to read. The DayOfWeek is 6, which agency FRIDAY because it starts amongst SUNDAY beingness 1.
DayOfMonth is fine every bit it denotes 17th, which is good. The twenty-four hr menses of the yr too looks skillful only await at the Month, most of the people think five agency May because that's the fifth Month only it agency June hither because the starting fourth dimension calendar month inward Calendar starts amongst 0, which is January. This consequence is sorted inward Java 8 yesteryear using Enum to stand upwards for DayOfWeek in addition to Month every bit an enumeration type. See Java SE 8 for Really Impatient to acquire to a greater extent than most novel Date in addition to Time API of Java 8.
You tin come across all values right away brand feel in addition to the API is too clear in addition to tardily to use. You don't ask to utilization whatever other course of written report similar Calendar to extract private fields from Date inward Java 8. This is a groovy payoff inward price of readability, maintainability, in addition to ease of debugging. You tin farther read Java 8 inward Action to acquire to a greater extent than most using the LocalDate course of written report inward Java 8.
Java Program to obtain day, calendar month in addition to yr from Date in addition to LocalDate
You tin come across how tardily it is to extract the private engagement fields e.g. electrical current day, month, year, twenty-four hr menses of the week, twenty-four hr menses of the month, twenty-four hr menses of the yr inward Java 8. You should ever utilization novel Java 8 classes for novel code spell endeavor to refactor onetime code if at that spot is budget in addition to time.
That's all most how to acquire the day, month, in addition to a yr from a Date inward Java. We'have learned how to practise this mutual chore inward both Java 8 in addition to before version e.g. Java vi or 7. You tin come across it's much easier when y'all utilization the novel Date in addition to Time API inward Java 8. But, if y'all receive got to in addition to so brand certain y'all Calendar course of written report in addition to don't forget to laid the Date yesteryear calling setTime() method, without that Calendar volition hold out having the electrical current date.
Things are much improve inward Java 8, every bit it introduces new Date in addition to Time API. Here y'all tin utilization the LocalDate course of written report from java.time bundle to stand upwards for a date. This course of written report too has several acquire methods to recall dissimilar engagement related attribute e.g. getDayOfWeek() volition render Day of the week, getMonth() volition render Month, in addition to getYear() volition render year. The skillful affair most Java 8 Date API is that y'all don't ask to utilization whatever additional course of written report similar Calendar to extract engagement fields e.g. calendar month in addition to year.
Another skillful affair most java.time API is that it uses Enum for Month in addition to DayOfWeek, which agency a to a greater extent than meaningful in addition to right value is printed when y'all overstep the output to System.out.println() or log into your log file. Don't underestimate the value of this characteristic because it makes debugging quite easy.
You don't ask to guess if five is May or June inward a huge log file spell searching for a missing order. This is too the argue why Joshua Bloch advised to "use Enum over int pattern" to stand upwards for fixed divulge of things inward his all fourth dimension classic majority Effective Java. It makes the output to a greater extent than readable in addition to debugging easier.
How to acquire Day, Month in addition to Year inward Java 6,7
As I said y'all tin utilization the java.util.Calendar course of written report to extract month, year, day, dayOfMonth, dayOfWeek, in addition to dayOfYear from a given Date inward Java. You tin acquire the Calendar illustration local to your organisation in addition to fourth dimension zone yesteryear calling the Calendar.getInstance() method.Once y'all acquire that, y'all ask to laid the Date to Calendar yesteryear calling setTime() method. It's 1 of the common mistakes inward Java to forget setting Date to Calendar, which leads to wrong output in addition to subtle bugs. There is no compile fourth dimension error because yesteryear default Calendar is laid to the current date inward Java.
Once y'all got a Calendar instance, y'all tin extract whatever engagement related or time-related plain yesteryear using get() method, which takes an int value, denoting the constant defined inward Calendar for that plain e.g. Month, Year, or DayOfWeek every bit shown inward the next example:
Date today = new Date(); // Friday Jun 17 14:54:28 PDT 2016 Calendar cal = Calendar.getInstance(); cal.setTime(today); // don't forget this if engagement is arbitrary e.g. 01-01-2014 int dayOfWeek = cal.get(Calendar.DAY_OF_WEEK); // 6 int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH); // 17 int dayOfYear = cal.get(Calendar.DAY_OF_YEAR); //169 int calendar month = cal.get(Calendar.MONTH); // 5 int yr = cal.get(Calendar.YEAR); // 2016
You tin come across that this method render an int value which is non real meaningful except the Year part. Thankfully, Calendar corrected 1 error of java.util.Date course of written report which returns engagement from 1900 only residuum of them is withal similar to java.util.Date in addition to hard to read. The DayOfWeek is 6, which agency FRIDAY because it starts amongst SUNDAY beingness 1.
DayOfMonth is fine every bit it denotes 17th, which is good. The twenty-four hr menses of the yr too looks skillful only await at the Month, most of the people think five agency May because that's the fifth Month only it agency June hither because the starting fourth dimension calendar month inward Calendar starts amongst 0, which is January. This consequence is sorted inward Java 8 yesteryear using Enum to stand upwards for DayOfWeek in addition to Month every bit an enumeration type. See Java SE 8 for Really Impatient to acquire to a greater extent than most novel Date in addition to Time API of Java 8.
Getting Month, Year in addition to Day of Date inward Java 8
So, nosotros know how to acquire these value inward Java vi in addition to Java 7, right away it's fourth dimension to await at how to acquire calendar month in addition to yr from the engagement inward Java 8. As I said, y'all tin utilization LocalDate to stand upwards for a engagement inward Java 8. It's a pure engagement value without whatever fourth dimension chemical constituent inward it e.g. "14-12-2016" or "20161214". The LocalDate course of written report too provides several getter methods to extract these values every bit shown below:LocalDate currentDate = LocalDate.now(); // 2016-06-17 DayOfWeek dow = currentDate.getDayOfWeek(); // FRIDAY int dom = currentDate.getDayOfMonth(); // 17 int doy = currentDate.getDayOfYear(); // 169 Month thousand = currentDate.getMonth(); // JUNE int y = currentDate.getYear(); // 2016
You tin come across all values right away brand feel in addition to the API is too clear in addition to tardily to use. You don't ask to utilization whatever other course of written report similar Calendar to extract private fields from Date inward Java 8. This is a groovy payoff inward price of readability, maintainability, in addition to ease of debugging. You tin farther read Java 8 inward Action to acquire to a greater extent than most using the LocalDate course of written report inward Java 8.
Java Program to acquire day, month, yr from Date inward Java 8
Here is our sample Java programme to obtain electrical current day, month, in addition to the yr from a Date inward Java. In this example, I receive got shown y'all how to attain this inward both Java 8 in addition to previous versions e.g. JDK vii or JDK 6. In Java 8, I receive got used novel Date in addition to Time API which agency engagement refer hither to LocalDate, LocalDateTime, or ZonedDateTime, spell inward previous version engagement refers to java.util.Date object.
Java Program to obtain day, calendar month in addition to yr from Date in addition to LocalDate
package test; import java.time.DayOfWeek; import java.time.LocalDate; import java.time.Month; import java.util.Calendar; import java.util.Date; /** * Java Program to acquire electrical current day, month, year, in addition to dayOfweek inward both Java 8 * in addition to before e.g. JDK 1.6 in addition to JDK 1.7 */ public class Test { public static void main(String[] args) { // Before Java 8 Date today = new Date(); Calendar cal = Calendar.getInstance(); cal.setTime(today); // don't forget this if engagement is arbitrary int dayOfWeek = cal.get(Calendar.DAY_OF_WEEK); // 1 beingness Sunday int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH); int dayOfYear = cal.get(Calendar.DAY_OF_YEAR); int calendar month = cal.get(Calendar.MONTH); // 0 beingness January int year = cal.get(Calendar.YEAR); System.out.println("current engagement : " + today); System.out.println("dayOfWeek from engagement inward Java vi : " + dayOfWeek); System.out.println("dayOfMonth from a engagement inward Java vii : " + dayOfMonth); System.out.println("dayOfYear from a engagement inward Java 1.6 : " + dayOfYear); System.out.println("month from a engagement inward Java 1.7 : " + month); System.out.println("year from engagement inward JDK vi : " + year); // In Java 8 LocalDate currentDate = LocalDate.now(); DayOfWeek dow = currentDate.getDayOfWeek(); int dom = currentDate.getDayOfMonth(); int doy = currentDate.getDayOfYear(); Month thousand = currentDate.getMonth(); int y = currentDate.getYear(); System.out.println("current local engagement : " + currentDate); System.out.println("dayOfWeek from a engagement inward Java 8 : " + dow); System.out.println("dayOfMonth from engagement inward JDK 8: " + dom); System.out.println("dayOfYear from a engagement inward Java SE 8 : " + doy); System.out.println("month from a engagement inward Java 1.8 : " + m); System.out.println("year from engagement inward JDK 1.8 : " + y); } } Output electrical current engagement : Friday Jun 17 14:54:28 SGT 2016 dayOfWeek from engagement in Java 6 : 6 dayOfMonth from a engagement in Java 7 : 17 dayOfYear from a engagement in Java 1.6 : 169 calendar month from a engagement in Java 1.7 : 5 year from engagement in JDK 6 : 2016 electrical current local engagement : 2016-06-17 dayOfWeek from a engagement in Java 8 : FRIDAY dayOfMonth from engagement in JDK 8: 17 dayOfYear from a engagement in Java SE 8 : 169 calendar month from a engagement in Java 1.8 : JUNE year from engagement in JDK 1.8 : 2016
You tin come across how tardily it is to extract the private engagement fields e.g. electrical current day, month, year, twenty-four hr menses of the week, twenty-four hr menses of the month, twenty-four hr menses of the yr inward Java 8. You should ever utilization novel Java 8 classes for novel code spell endeavor to refactor onetime code if at that spot is budget in addition to time.
That's all most how to acquire the day, month, in addition to a yr from a Date inward Java. We'have learned how to practise this mutual chore inward both Java 8 in addition to before version e.g. Java vi or 7. You tin come across it's much easier when y'all utilization the novel Date in addition to Time API inward Java 8. But, if y'all receive got to in addition to so brand certain y'all Calendar course of written report in addition to don't forget to laid the Date yesteryear calling setTime() method, without that Calendar volition hold out having the electrical current date.
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