datesixthtry.java

java编程代码

import java.util.Scanner;

public class DateSixthTry
{
    private String month;
    private int day;
    private int year; //a four digit number.

    public void setDate(int monthInt, int day, int year)
    {
        if (dateOK(monthInt, day, year))
        {
            this.month = monthString(monthInt);
            this.day = day;
            this.year = year;
        }
        else
        {
            System.out.println("Fatal Error");
            System.exit(0);
        }
    }

    public void setDate(String monthString, int day, int year)
    {
        if (dateOK(monthString, day, year))
        {
            this.month = monthString;
            this.day = day;
            this.year = year;
        }
        else
        {
            System.out.println("Fatal Error");
            System.exit(0);
        }
    }

    public void setDate(int year)
    {
        setDate(1, 1, year);
    }

    private boolean dateOK(int monthInt, int dayInt, int yearInt)
    {
        return ( (monthInt >= 1) && (monthInt <= 12) &&
                 (dayInt >= 1) && (dayInt <= 31) &&
                 (yearInt >= 1000) && (yearInt <= 9999) );
    }

    private boolean dateOK(String monthString, int dayInt, int yearInt)
    {
        return ( monthOK(monthString) &&
                 (dayInt >= 1) && (dayInt <= 31) &&
                 (yearInt >= 1000) && (yearInt <= 9999) );
    }

    private boolean monthOK(String month)
    {
        return (month.equals("January") || month.equals("February") ||
                month.equals("March") || month.equals("April") ||
                month.equals("May") || month.equals("June") ||
                month.equals("July") || month.equals("August") ||
                month.equals("September") || month.equals("October") ||
                month.equals("November") || month.equals("December") );
    }


     public void readInput( )
     {
         boolean tryAgain = true;
         Scanner keyboard = new Scanner(System.in);
         while (tryAgain)
         {
             System.out.println("Enter month, day, and year.");
               System.out.println("Do not use a comma.");
             String monthInput = keyboard.next( );
             int dayInput = keyboard.nextInt( );
             int yearInput = keyboard.nextInt( );
             if (dateOK(monthInput, dayInput, yearInput) )
             {
                 setDate(monthInput, dayInput, yearInput);
                 tryAgain = false;
             }
             else
                 System.out.println("Illegal date. Reenter input.");
          }
     }


    public void writeOutput( )
    {
        System.out.println(month + " " + day + ", " + year);
    }

    public void setMonth(int monthNumber)
    {
        if ((monthNumber <= 0) || (monthNumber > 12))
        {
            System.out.println("Fatal Error");
            System.exit(0);
        }
        else
            month = monthString(monthNumber);
    }

    public void setDay(int day)
    {
        if ((day <= 0) || (day > 31))
        {
            System.out.println("Fatal Error");
            System.exit(0);
        }
        else
            this.day = day;
    }

    public void setYear(int year)
    {
        if ( (year < 1000) || (year > 9999) )
        {
            System.out.println("Fatal Error");
            System.exit(0);
        }
        else
            this.year = year;
    }

    public boolean equals(DateSixthTry otherDate)
    {
        return ( (month.equalsIgnoreCase(otherDate.month))
                  && (day == otherDate.day) && (year == otherDate.year) );
    }
    public boolean precedes(DateSixthTry otherDate)
    {
        return ( (year < otherDate.year) ||
           (year == otherDate.year && getMonth( ) < otherDate.getMonth( )) ||
           (year == otherDate.year && month.equals(otherDate.month)
                                         && day < otherDate.day) );
    }

    public String toString( )
    {
        return (month + " " + day + ", " + year);
    }

    public int getDay( )
    {
        return day;
    }

    public int getYear( )
    {
        return year;
    }

    public int getMonth( )
    {
        if (month.equalsIgnoreCase("January"))
            return 1;
        else if (month.equalsIgnoreCase("February"))
            return 2;
        else if (month.equalsIgnoreCase("March"))
            return 3;
        else if (month.equalsIgnoreCase("April"))
            return 4;
        else if (month.equalsIgnoreCase("May"))
            return 5;
        else if (month.equals("June"))
            return 6;
        else if (month.equalsIgnoreCase("July"))
            return 7;
        else if (month.equalsIgnoreCase("August"))
            return 8;
        else if (month.equalsIgnoreCase("September"))
            return 9;
        else if (month.equalsIgnoreCase("October"))
            return 10;
        else if (month.equalsIgnoreCase("November"))
            return 11;
        else if (month.equalsIgnoreCase("December"))
            return 12;
        else
        {
            System.out.println("Fatal Error");
            System.exit(0);
            return 0; //Needed to keep the compiler happy
        }
    }


    private String monthString(int monthNumber)
    {
        switch (monthNumber)
        {
        case 1:
            return "January";
        case 2:
            return "February";
        case 3:
            return "March";
        case 4:
            return "April";
        case 5:
            return "May";
        case 6:
            return "June";
        case 7:
            return "July";
        case 8:
            return "August";
         case 9:
            return "September";
        case 10:
            return "October";
        case 11:
            return "November";

        case 12:
            return "December";
        default:
            System.out.println("Fatal Error");
            System.exit(0);
            return "Error"; //to keep the compiler happy
        }
    }
}