The assignment is to create my own Date class. Restriction is that we cannot use the library date class. Here is what I have..

 public class Date {

/* Use array to convert integer month into
  month string abbreviation */
public String convertMonth(int month) {
    String[] m = new String[12];
    m[0] = "JAN";
    m[1] = "FEB";
    m[2] = "MAR";
    m[3] = "APR";
    m[4] = "MAY";
    m[5] = "JUN";
    m[6] = "JUL";
    m[7] = "AUG";
    m[8] = "SEP";
    m[9] = "OCT";
    m[10] = "NOV";
    m[11] = "DEC";

    return m[month - 1];

}

private int month;
private int day;
private int year;

/* default constructor */
Date () {
    month = 1;
    day = 1;
    year = 2000;

}

public Date (int month, int day, int year) {
   //check if entry is valid
    if (year < 0)
        throw new IllegalArgumentException("Year must be positive >0");
    if (month < 1 || month > 12)
        throw new IllegalArgumentException("The month bust be between 1 and 12 inclusive");
    if (day < 1 || day > 31)
        throw new IllegalArgumentException("Day value " + day + " is invalid for month " + month);

    this.month = month;
    this.day = day;
    this.year = year;

    System.out.printf("%s\n", this);

}

// convert into MMM-DD-YYYY format
public String toString() {

    return String.format(convertMonth(month) + "-%02d-%04d", day, year);
}

// return true if the receiving date and parameter date are equal
public boolean equals(Date other) {

    Date Date = new Date();
    if (Date.equals(other)) {
        return true;
    }
    else return false;
}