test1

Class TimeUtil

java.lang.Object

test1.TimeUtil

public class TimeUtil
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static int	DAYS_PER_LEAP_YEAR The number of days in a leap year.
static int	DAYS_PER_YEAR The number of days in a standard year.
static int	MINUTES_PER_HOUR The number of minutes in one hour.

Method Summary

Modifier and Type	Method and Description
static boolean	isLeapYear(int year) Returns true if year is a leap year and false otherwise.
static int	mostFrequent(List<Integer> years) Given a sorted list of years, returns the year that occurs most frequently in the list.
static int	toHoursRoundedUp(int minutes) Converts a number of minutes to hours rounding up to the nearest number of hours.
static int	totalDays(int startYear, int endYear) Computes the total number of days in the period of time from Jan 1 of the start year to Dec 31 of the end year accounting for the presence of leap years.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MINUTES_PER_HOUR

public static final int MINUTES_PER_HOUR

The number of minutes in one hour.

See Also:

Constant Field Values

DAYS_PER_YEAR

public static final int DAYS_PER_YEAR

The number of days in a standard year.

See Also:

Constant Field Values

DAYS_PER_LEAP_YEAR

public static final int DAYS_PER_LEAP_YEAR

The number of days in a leap year.

See Also:

Constant Field Values

Method Detail

toHoursRoundedUp

public static int toHoursRoundedUp(int minutes)

Converts a number of minutes to hours rounding up to the nearest number of hours. For example:

 toHoursRoundedUp(0)   returns   0
 toHoursRoundedUp(59)  returns   1
 toHoursRoundedUp(60)  returns   1
 toHoursRoundedUp(61)  returns   2
 toHoursRoundedUp(150) returns   3
 

This is how most service-based businesses calculate how many hours of labor are charged to the customer (i.e., a job that takes 15 minutes will cost the customer 1 hour of labor charges).

Parameters:

minutes - a number of minutes

Returns:

the equivalent number of hours rounded up to the nearest hour

Precondition:

minutes is greater than or equal to zero

isLeapYear

public static boolean isLeapYear(int year)

Returns true if year is a leap year and false otherwise.

A year is always a leap year if it is evenly divisible by 400; for all other years, a year is a leap year if it is evenly divisible by 4 and not evenly divisible by 100. For example:

 isLeapYear(2000)  returns  true   (2000 is divisible by 400)
 isLeapYear(1900)  returns  false  (1900 is divisible by 4 and 100)
 isLeapYear(2004)  returns  true   (2004 is divisible by 4 but not 100)
 isLeapYear(2005)  returns  false  (2005 is not divisible by 4)
 

Parameters:

year - a year

Returns:

true if year is a leap year and false otherwise

Throws:

IllegalArgumentException - if year is less than zero

totalDays

public static int totalDays(int startYear,
                            int endYear)

Computes the total number of days in the period of time from Jan 1 of the start year to Dec 31 of the end year accounting for the presence of leap years.

 totalDays(2000, 2000)  returns  366        (Jan 1, 2000 to Dec 31, 2000)
 totalDays(2001, 2002)  returns  365 + 365  (Jan 1, 2001 to Dec 31, 2002)
 totalDays(2001, 2004)  returns  365 + 365 + 365 + 366  (Jan 1, 2001 to Dec 31, 2004)
 

Parameters:

startYear - the start year

endYear - the end year

Returns:

the number of days from Jan 1 of the start year to Dec 31 of the end year

Precondition:

endYear is greater than or equal to startYear

mostFrequent

public static int mostFrequent(List<Integer> years)

Given a sorted list of years, returns the year that occurs most frequently in the list. You may assume that only one year occurs the most frequently in the argument list. The method does not modify the argument list.

Parameters:

years - a sorted list of years

Returns:

the year that occurs most frequently in the list

Precondition:

years.size() is greater than or equal to 1