Enjoy with LocalDateTime in Java 8

LocalDateTime class is an immutable class. It is thread safe.
This class provides output in the form of date and time such as 20019-07-29T10:15:30.
We use LocalDateTime instance for general-purpose date and time information. It has no time zone data.

How to import this class?

This class is available in java.time package.
By writing this statement "import java.time.LocalDateTime;" we can import a class

How to create an instance of LocalDateTime class?

1.  By invoking a static method in LocalDateTime class i.e. now() method  

           LocalDateTime ldt = LocalDateTime.now();

2. Bypassing year, month, day, hour, minute, second and nanosecond values to of() method. This of() method is also a static method.

           LocalDateTime ldt = LocalDateTime.of(2019,07,29,6,30,40,50000);

This method is overloaded and one of them takes argument at LocalDate and LocalTime.

           LocalDateTime ldt = LocalDateTime.of(LocalDate.now(), LocalTime.now());

3. By passing date time string representation as an argument i.e.

           LocalDateTime ldt = LocalDateTime.parse("2019-07-29T22:11:03.460446");

How to Retrieving Date Time Information from LocalDateTime?

1. int getHour(): this method returns the hour contained within the LocalDateTime object, from 0 to 23.
2. int getMinute(): this method returns the minute information, from 0 to 59.
3. int getSecond():  this method returns the second contained within the LocalDateTime object, from 0 to 59.
4. int getNano():  this method returns the nanosecond from the LocalDateTime object, ranging from 0 to 999,999,999.

This LocalDateTime class has different methods to plus and minus date time components. These methods return a new instance if LocalDateTime. But do not perform any changes in the existing instance as this class is immutable.

Let's see these methods:

1. plusHours(), plusMinutes(), plusSeconds(), plusNanos() : these methods adding time component in LocalDateTime object.
2. minusHours(), minusMinutes(), minusSeconds() and minusNanos(): these methods subtracting time component in LocalDateTime object.
3. plusYears(), plusMonths(), plusWeeks(), plusDays() : these methods adding date component in LocalDateTime object.
4. minusYears(), minusMonths(), minusWeeks(),  minusDays() : these methods subtracting date component in LocalDateTime object.

As the name of these methods itself suggests that what these methods are used for. All the methods take a long type of argument and return a new instance of LocalDateTime.