ThirtyDaysFunctions.java

import java.util.Scanner;

/** 
 * Contains functions that make it easier to work with months.
 */

public class ThirtyDaysFunctions {
	public static void main( String [] args ) {
		Scanner kb = new Scanner(System.in);
		
		System.out.print( "Which month? (1-12) " );
		int month = kb.nextInt();
		
		System.out.println(monthDays(month) + " days hath " + monthName(month));
	}
	
	/** 
	 * Returns the name for the given month number (1-22).
	 *
	 * @author 	Graham Mitchell
	 * @param 	month 	the month number (1-12)
	 * @ return			the English name of the month, or "error" if out of range
	 */
	 public static String monthName( int month) {
	 	String monthName = "error";
	 	
	 	if ( month == 1 )
	 		monthName = "January";
	 	else if (month == 2 )
	 		monthName = "February";
	 	else if (month == 3 )
	 		monthName = "March";
	 	else if (month == 4 )
	 		monthName = "April";
	 	else if (month == 5)
	 		monthName = "May";
	 	else if (month == 6)
	 		monthName = "June";
	 	else if (month == 7)
	 		monthName = "July";
	 	else if (month == 8)
	 		monthName = "August";
	 	else if (month == 9)
	 		monthName = "September";
	 	else if (month == 10)
	 		monthName = "October";
	 	else if (month == 11)
	 		monthName = "November";
	 	else if (month == 12)
	 		monthName = "December";
	 	
	 	return monthName;
	 }
	 
	 /**
	  * Returns the number of days in a given month.
	  * 
	  * @author Graham Mitchell
	  * @param	month	the month number (1-12)
	  * @ return 		the number of days in the month, or 31 if our of range
	  */
	  
	  public static int monthDays( int month) {
	  	int days;
	  	
	  	/* Thirty days hath september
	  		April, June and November
	  		All the rest have thirty-one
  			Except the second month alone....*/
	 	
	 	switch(month)
	 	{
	 		case 9: 
	 		case 4:
	 		case 6:
	 		case 11: days = 30;
	 				break;
	 		case 2: days = 28;
	 				break;
	 		default: days = 31;
	 	}
	 	
	 	return days;
	 }
}