Emp.Java
public class Emp
{
private String firstName;
private String lastName;
private Date birthDate;
private Date hireDate;
//constructor to initialize name, birth date, and hire date
public Emp (String first, String last, Date dateOfBirth, Date dateOfHire)
{
firstName = first;
lastName = last;
birthDate = dateOfBirth;
hireDate = dateOfHire;
}
//convert Emp to String format
public String toString()
{
return String.format(“%s, %s Hired: %s Birthday: %s”,
lastName, firstName, hireDate, birthDate);
}
}
Date.Java
//Date class declaration
public class Date
{
private int month; //1-12
private int day; //1-31 based on month
private int year; //any year
//constructor: call checkMonth to confirm proper value for month
//call checkDay to confirm proper value for day
public Date(int theMonth, int theDay, int theYear)
{
month = checkMonth(theMonth); //validate month
year = theYear; //could validate year
day = checkDay(theDay); //validate day
System.out.printf(“Date object constructor for date %s\n”, this);
}
//utility method to confirm proper month value
private int checkMonth (int testMonth)
{
if (testMonth>0 && testMonth <=12) //validate month
return testMonth;
else //month is invalid
{
System.out.printf(“Invalid month (%d) set to 1.”, testMonth);
return 1; //maintain object in consistent state
}
}
//utility method to confirm proper day value based on month and year
private int checkDay (int testDay)
{
//0 is ignored since daysPerMonth[0]=0 represents 0 months
//Month starts on the 2nd element after 0 (from 1-12)
int daysPerMonth[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
//check if day in range for month
if (testDay >= 1 && testDay <= daysPerMonth[month])
return testDay;
//check for leap year
if (month == 2 && testDay == 29 && (year % 400==0 ||
(year % 4 == 0 && year % 100 != 0)))
return testDay;
System.out.printf(“Invalid day (%d) set to 1.”, testDay);
return 1; //maintain object in consistent state
}
//return a String of the form month/day/year
//automatically invoked even without calling this method
public String toString()
{
return String.format(“%d/%d/%d”, month, day, year);
}
}
EmpTest.Java
//composition demonstration
public class EmpTest
{
public static void main (String args[])
{
Date birth = new Date(7,0,1980);
Date hire = new Date(9,5,2007);
Emp employee = new Emp(“Ana”, “Santos”, birth, hire);
System.out.println(employee);
}
}
UST-ICS 