学步园

//Date类<br /> public class Date {<br /> private int month;<br /> private int day;<br /> private int year;</p> <p> public Date(int theMonth,int theDay,int theYear){<br /> month = checkMonth(theMonth);<br /> year = theYear;<br /> day = checkDay(theDay);<br /> System.out.println("Data object constructor for date"+ toDateString());<br /> }</p> <p> private int checkMonth(int testMonth){<br /> if (testMonth > 0 && testMonth <= 12)<br /> return testMonth;<br /> else{<br /> System.out.println("Invalid month("+ testMonth +")set to 1");<br /> return 1;<br /> }<br /> }</p> <p> private int checkDay(int testDay){<br /> int daysPerMonth[] = {0,31,28,31,30,31,30,31,31,30,31,30,31};<br /> if(testDay >0 && testDay <= daysPerMonth[month])<br /> return testDay;</p> <p> if(month ==2 && testDay ==29 && (year %400 ==0 ||<br /> (year %4 ==0 && year %100 != 0)))<br /> return testDay;</p> <p> System.out.println("Invalid day ("+ testDay +")set to 1");</p> <p> return 1; </p> <p> }<br /> public String toDateString()<br /> {<br /> return month + "/" + day + "/" + year;<br /> }</p> <p>}<br /> //Employee类中应用Date类<br /> public class Employee {<br /> private String firstName;<br /> private String lastName;<br /> private Date birthDate;<br /> private Date hireDate;</p> <p> public Employee(String first,String last,Date dateofBirth,<br /> Date dateofHire)<br /> {<br /> firstName = first;<br /> lastName = last;<br /> birthDate = dateofBirth;<br /> hireDate = dateofHire;<br /> }<br /> public String toEmployeeString()<br /> {<br /> return lastName + "," + firstName + " Hired:" + hireDate.toDateString()+<br /> "Birthday:"+birthDate.toDateString();</p> <p> }<br /> }<br /> //程序入口<br /> import javax.swing.JOptionPane;<br /> public class EmployeeTest {</p> <p> public static void main(String[] args) {<br /> Date birth = new Date(7,24,1949);<br /> Date hire = new Date(3,12,1988);<br /> Employee employee = new Employee("Bob","Jones",birth,hire);</p> <p> JOptionPane.showMessageDialog(null,employee.toEmployeeString(),"Testing Class Employee",<br /> JOptionPane.INFORMATION_MESSAGE);</p> <p> System.exit(0);</p> <p> }</p> <p>}