dateTime

Question 1

What package do you import for date and time?

Answer 1

import java.time.*;

Question 2

When do you use LocalDate?
Print the current local Date

Answer 2

Your birthday -> just no time
LocalDate.now();

Question 3

LocalTime?

Answer 3

Contains just time and no date and no timezone.
Hours, minutes, seconds and nanoseconds

LocalTime.now();

Question 4

LocalDateTime

Answer 4

Contains date and time but no timezone
date and time
LocalDateTime.now();

Question 5

Can you use LocalDate and define the method signature?

Answer 5

public static LocalDate of(int year, int month, int day)
public static LocalDate of(int year, Month month, int day)

Question 6

Can you use LocalTime and define the method signature?

Answer 6

LocalTime time1 = LocalTime.of(6,16);

1. hour and minute
2. hour, minute and second
3. hour, minute, second and nanosecond

Question 7

Can you use LocalDateTime and define the method signature?

Answer 7

LocalDateTime time = LocalDateTime.of(date, month,day, hour, month, second, nanos);

Question 8

Can you do this?
~~~

LocalDate a = new LocalDate();

~~~

Answer 8

NO because the only way you can do is by
LocalDate a = LocalDate.of(2022, 1,3);

It’s static method.

Question 9

Can you do the following:

LocalDate.of(2022, Month.JANUARY, 40);

Answer 9

Throws DateTimeException

Question 10

Are Date and time classes mutable or immutable?

Answer 10

Immutable

Question 11

Given the following:
Can you add weeks, days, months and years?
Can you subtract them as well?

~~~

LocalDate date = LocalDate.of(2022, Month.JANUARY, 20);

````

Answer 11

date.plusDays(2);
date.plusWeeks(1);
date.plusMonths(1);
date.plusYears(1);

date.minusDays(2);

Question 12

What does this print?

LocalDate date = LocalDate.of(2020, Month.JANUARY,20);
date.plusDays(10);
System.out.println(date);

Answer 12

It will pring 20th January 2020 because date and time class are immutable

Question 13

What is the output of the following?
~~~

LocalDate date = LocalDate.of(2020, Month.JANUARY, 20);
date = date.plusMinutes(1);

~~~

Answer 13

Does not compile

Question 14

Can you call the following on LocalDate?

plusYears/minusYears
plusMonths
plusWeeks
plusDays
plusHours
plusMinutes
plusSeconds
plusNanos

Answer 14

plusYears/minusYears - yes
plusMonths - yes
plusWeeks - yes
plusDays - yes
plusHours - no
plusMinutes -no
plusSeconds - no
plusNanos -no

Question 15

Can you call the following on LocalTime?

plusYears/minusYears
plusMonths
plusWeeks
plusDays
plusHours
plusMinutes
plusSeconds
plusNanos

Answer 15

plusYears/minusYears - no
plusMonths - no
plusWeeks - no
plusDays - no
plusHours - yes
plusMinutes - yes
plusSeconds - yes
plusNanos - yes

Question 16

Can you LocalDateTime?
plusYears/minusYears
plusMonths
plusWeeks
plusDays
plusHours
plusMinutes
plusSeconds
plusNanos

Answer 16

All yes
plusYears/minusYears
plusMonths
plusWeeks
plusDays
plusHours
plusMinutes
plusSeconds
plusNanos

Question 17

Can Period be chainable?

Answer 17

No

Question 18

Create a date format?

Answer 18

LocalDate date = LocalDate.of(2022, Month.January, 1);
DateTimeFormatter a = DateTimeFormatter.ofLocalizedDate(FormatStyle.SHORT);
System.out.println(a.format(date));

Question 19

What is the point of using the Period class?

Answer 19

Period class represents a number of days, months, years to add or subtract from a Local Date or LocalDateTime.

Question 20

LocalDate
Calling that on FormatStyle.SHORT
ofLocalizedDate

Answer 20

Shows the whole object

Question 21

How to format based on patterns?

Answer 21

DateFormatter f = DateFormatter.ofPattern("MMM dd",  yyyy);

Question 22

Make a LocalDateTime and make a dateTimeFormatter

Answer 22

LocalDateTime date = LocalDateTime.of(2023, 1, 1, 2,3,3);

	DateTimeFormatter a = DateTimeFormatter.ofPattern("yyyy, MMMM, m, dd");
	System.out.println(a.format(date));

Question 23

Of the DataFormatter patterns,
What does the following mean?
M
MMMM
MM
MMM

Answer 23

M means month
M =1;
MMMM = January
MM = 01;
MMM = Jan

Question 24

What does dd represent, hh, yyyyy, mm?

Answer 24

d represents day,
yyyy represents year
hh represents hour
: if you want to output the colon
mm = minute

Question 25

LocalDate date = LocalDate.of(2018, Month.APRIL, 40);
System.out.println(date.getYear() + “ “ + date.getMonth() + “ “
+ date.getDayOfMonth());

Answer 25

exception is thrown

mistake so know this.

Question 26

LocalDateTime d = LocalDateTime.of(2015, 5, 10, 11, 22, 33);
Period p = Period.ofDays(1).ofYears(2);
d = d.minus(p);
DateTimeFormatter f = DateTimeFormatter.ofLocalizedDateTime(FormatStyle
.SHORT);
System.out.println(f.format(d));

Answer 26

I will be

Year = 2015 -2

The reason is period wont allow chaining so last gets processed.
Mistake.

Question 27

Can you do this?
Period a = Period.ofDays(-14);

Answer 27

You can add both negative and positives.

Question 28

What happens when you try to use time with LocalDate

Answer 28

DNC