Programımdaki hesaplamalar yanlış çıktı, ancak kod doğru görünüyor mu?

import java.util.Scanner; 
import java.util.InputMismatchException;

public class date {
public static int t1;           //integers for methods
public static int t2;
public static int x = 0;        //integer for looping
public static int y1;
public static int m1;
public static int d1;
public static int y2;
public static int m2;
public static int d2;

public static void date1() {
    do                                                                      //along with "while" statement. Makes loop if error occurs
{   
    Scanner scanner = new Scanner(System.in);
    try {                                                                  //try (run program as normal)
        System.out.println("Please enter the first date ");
        System.out.println("Please enter the year: ");                      //entering date
        y1 = scanner.nextInt();

        System.out.println("Please enter the month: ");
        m1 = scanner.nextInt();

        System.out.println("Please enter the day: ");
        d1 = scanner.nextInt();
        break;                                                             //break loop if input is correct
    } catch (InputMismatchException inputMismatchException) {              //response to "Try". if input is incorrect error will be displayed
        scanner.nextLine();
        System.err.println("You must enter intergers. Please try again. ");
    }
     x = x + 1 ;                                                               //set loop to three attempts
}   while (x < 3) ;                                                         //do process occurs while attempts are under < 4

}

public static void caldate1() {
    do                                                                      //along with "while" statement. Makes loop if error occurs
{   
    int j = 693502;
    try {
        if (m1 == 1 || m1 == 3 || m1 == 5 || m1 == 7 || m1 == 8 || m1 == 10 //if/else statements to set proper numbers of days in each month
                || m1 == 12) {
            t1 = ((365 * y1) + d1 + 31);
        } else if (m1 == 2) {
            t1 = ((365 * y1) + d1 + 28);
        } else if (m1 == 4 || m1 == 6 || m1 == 9 || m1 == 11) {
            t1 = ((365 * y1) + d1 + 30);
        }
        if (t1 >= j)                                                        //if/else statement to catch error if date inputted isnt over jan 1st 1900
        { break;}                                                          //break loop if date is greater or equal to jan 1st 1900
        else {
            System.err.printf("Please enter a date after Jan 1st 1900.\n");
        }
    } catch (InputMismatchException inputMismatchException) {                   //error if date too small
        System.err.println("You must enter intergers. Please try again. ");
    }
     x = x + 1 ;                                                               //set loop to three attempts
    }   while (x < 3) ; 
}

public static void date2() {
    do                                                                     //process to follow if length == 5
{   
    Scanner scanner = new Scanner(System.in);
    try  {                                                                 //try (run program as normal)
        System.out.println("Please enter the second date ");
        System.out.println("Please enter the year: ");                      //entering second date
        y2 = scanner.nextInt();

        System.out.println("Please enter the month: ");
        m2 = scanner.nextInt();

        System.out.println("Please enter the day: ");
        d2 = scanner.nextInt();
          break;                                                               //break loop if input is correct
    } catch (InputMismatchException inputMismatchException) {              //  response to "try". if input is incorrect error will be displayed
        scanner.nextLine();
        System.err.println("You must enter intergers. Please try again. ");
    }
     x = x + 1 ;                                                               //set loop to three attempts
}   while (x < 3)  ;                                                            //do process occurs while attempts are under < 4

}

public static void caldate2() {
     do                                                                 //all code is same as in caldate1()... just second set of variables.
{   
    int j = 693502;
    try {
        if (m2 == 1 || m2 == 3 || m2 == 5 || m2 == 7 || m2 == 8 || m2 == 10
                || m2 == 12) {
            t2 = ((365 * y2) + d2 + 31);
        } else if (m2 == 2) {
            t2 = ((365 * y2) + d2 + 28);
        } else if (m2 == 4 || m2 == 6 || m2 == 9 || m2 == 11) {
            t2 = ((365 * y2) + d2 + 30);
        }
        if (t2 >= j) 
        { break;}
        else {
            System.err.printf("Please enter a date after Jan 1st 1900.\n");
        }
    } catch (InputMismatchException inputMismatchException) {
        System.err.println("You must enter intergers. Please try again. ");
    }
     x = x + 1  ;                                                              //set loop to three attempts
    }   while (x < 3) ; 
}
public static void finaldate1() {
    x = Math.abs(t1 - t2);  //calculate total day difference. output absolute value so that result is always positive
    System.out.println("The difference between the two dates is: " + x  + " days.");    
}

public static void main(String[] args) {

    date1();
    caldate1();
    date2();
    caldate2();
    finaldate1();


}
    }

Örneğin, 28 Şubat 2011 ve 1 Mart 2011’de Gün sayısı 1 olmalıdır. Henüz 24 hesaplar. Sorunun ne olabileceğini bilen var mı? Çünkü başka tarihler girdiğimde tarihleri ​​iyi hesaplar.