GregorianCalendar issues - how to display?

[James Brooks]

Hi again!

Now I'm having trouble with displaying the GregorianCalendar dates. Code is below, but what is happening is that my GregorianCalendar objects are always displaying 2/1/5 as the date, no matter what values I instantiate them with or set them with via the mutator method. Can someone tell/show me the correct way to display such an object? Thanks!

import java.util.GregorianCalendar;
import javax.swing.JOptionPane;
public class CollegeStudent
{
    String first, last;
    GregorianCalendar enrollDate, projectedGradDate;
    
    public CollegeStudent(String f, String l, GregorianCalendar eD, GregorianCalendar pGD)
    {
        first = f;
        last = l;
        enrollDate = eD;
        projectedGradDate = pGD;        
    }
    
    public void getFirst()
    {
        JOptionPane.showMessageDialog(null, "The first name is " + first);
    }
    public void setFirst(String fn)
    {
        first = fn;
    }
    public void getLast()
    {
        JOptionPane.showMessageDialog(null, "The last name is " + last);
    }
    public void setLast(String ln)
    {
        last = ln;
    }
    public void getEnrollDate()
    {
       
        JOptionPane.showMessageDialog(null, "The enrollment date is " + enrollDate.MONTH + "/" 
                + enrollDate.DAY_OF_MONTH + "/" + enrollDate.YEAR);
    }
    public void setEnrollDate()
    {
        int m = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the new enrollment month:", "Enter enroll month",
                JOptionPane.INFORMATION_MESSAGE));
        int d = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the new enrollment day:", "Enter enroll day",
                JOptionPane.INFORMATION_MESSAGE));
        int y = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the new enrollment year:", "Enter enroll year",
                JOptionPane.INFORMATION_MESSAGE));
        GregorianCalendar myCalendarDate = new GregorianCalendar(y, m, d);
        enrollDate = myCalendarDate;
    }
    public void getProjectedGradDate()
    {
        JOptionPane.showMessageDialog(null, "The projected graduation date is " + projectedGradDate.MONTH + "/" 
                + projectedGradDate.DAY_OF_MONTH + "/" + projectedGradDate.YEAR);
    }
    public void setProjectedGradDate()
    {
        int m = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the projected graduation month:", "Enter grad month", 
                JOptionPane.INFORMATION_MESSAGE));
        int d = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the projected graduation day:", "Enter grad day", 
                JOptionPane.INFORMATION_MESSAGE));
        int y = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the projected graduation year:", "Enter grad year", 
                JOptionPane.INFORMATION_MESSAGE));
        GregorianCalendar newGradDate = new GregorianCalendar(y, m, d);
        projectedGradDate = newGradDate;
    }
    public static void main(String[] args)
    {
        GregorianCalendar enrollD = new GregorianCalendar(2006, 3, 1);
        GregorianCalendar pGD = new GregorianCalendar(2007, 4, 30);
        CollegeStudent myStudent = new CollegeStudent("Patrick", "Brooks", enrollD, pGD);
        myStudent.getFirst();
        myStudent.getLast();
        myStudent.getEnrollDate();
        myStudent.getProjectedGradDate();
        myStudent.setEnrollDate();
        myStudent.getEnrollDate();
        myStudent.setProjectedGradDate();
        myStudent.setProjectedGradDate();
    }
}

[pete stein]

A java convention is that all-CAPS are constants or enumerations. What you think may be class properties (YEAR, MONTH,) is actually a constant that holds the field number for the get routine. If you call myDate.get(Calender.YEAR); you'll get the year. Same call with MONTH will give you the month. Check out Class Calender at javadocs. GregorianCalender derives from the Calender superclass, so all this applies to it.

Good luck!

[James Brooks]

Thanks for the help Pete, that 'cout << object.dataField' convention from C++ is still in my mind, I guess.

import java.util.GregorianCalendar;
import javax.swing.JOptionPane;
public class Main
{
    String first, last;
    GregorianCalendar enrollDate, projectedGradDate;
    
    public Main(String f, String l, GregorianCalendar eD, GregorianCalendar pGD)
    {
        first = f;
        last = l;
        enrollDate = eD;
        projectedGradDate = pGD;        
    }
    
    public void getFirst()
    {
        JOptionPane.showMessageDialog(null, "The first name is " + first);
    }
    public void setFirst(String fn)
    {
        first = fn;
    }
    public void getLast()
    {
        JOptionPane.showMessageDialog(null, "The last name is " + last);
    }
    public void setLast(String ln)
    {
        last = ln;
    }
    public void getEnrollDate()
    {
       
        JOptionPane.showMessageDialog(null, "The enrollment date is " + enrollDate.get(enrollDate.MONTH) + "/" 
                + enrollDate.get(enrollDate.DAY_OF_MONTH) + "/" + enrollDate.get(enrollDate.YEAR));
    }
    public void setEnrollDate()
    {
        int m = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the new enrollment month:", "Enter enroll month",
                JOptionPane.INFORMATION_MESSAGE));
        int d = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the new enrollment day:", "Enter enroll day",
                JOptionPane.INFORMATION_MESSAGE));
        int y = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the new enrollment year:", "Enter enroll year",
                JOptionPane.INFORMATION_MESSAGE));
        GregorianCalendar myCalendarDate = new GregorianCalendar(y, m, d);
        enrollDate = myCalendarDate;
    }
    public void getProjectedGradDate()
    {
        JOptionPane.showMessageDialog(null, "The projected graduation date is " + projectedGradDate.get(projectedGradDate.MONTH) + "/" 
                + projectedGradDate.get(projectedGradDate.DAY_OF_MONTH) + "/" + projectedGradDate.get(projectedGradDate.YEAR));
    }
    public void setProjectedGradDate()
    {
        int m = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the projected graduation month:", "Enter grad month", 
                JOptionPane.INFORMATION_MESSAGE));
        int d = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the projected graduation day:", "Enter grad day", 
                JOptionPane.INFORMATION_MESSAGE));
        int y = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter the projected graduation year:", "Enter grad year", 
                JOptionPane.INFORMATION_MESSAGE));
        GregorianCalendar newGradDate = new GregorianCalendar(y, m, d);
        projectedGradDate = newGradDate;
    }
    public static void main(String[] args)
    {
        GregorianCalendar enrollD = new GregorianCalendar(2006, 3, 1);
        GregorianCalendar pGD = new GregorianCalendar(2007, 4, 30);
        Main myStudent = new Main("Patrick", "Brooks", enrollD, pGD);
        myStudent.getFirst();
        myStudent.getLast();
        myStudent.getEnrollDate();
        myStudent.getProjectedGradDate();
        myStudent.setEnrollDate();
        myStudent.getEnrollDate();
        myStudent.setProjectedGradDate();
        myStudent.setProjectedGradDate();
    }
}