yesterday and tomorrow

import java.util.*;
public class date{
public static boolean isleapeyear(int y){
if(y%100==0){
return (y%400==0);}
else{
return (y%4==0);}
}

public static int daysinthemonth(int m,int y){
int d=0;
switch(m){
case 1:case 3:case 5:case 7:case 8:case 10:case 12:d=31;break;
case 4:case 6:case 9:case 11:d=30;break;
case 2:
if(isleapeyear(y)){
d=29;}
else {d=28;}break;
default:d=-1;
}
return d;
}

public void tomorrow(int d,int m,int y){
if((d==31)&&(m==12)){
System.out.print("tomorrow is"+" "+"1"+" "+"1"+" "+(y+1));
}
else if(d==daysinthemonth(m,y)){
System.out.print("tomorrow is "+"1"+" "+(m+1)+" "+(y));
}
else{
System.out.print("tomorrow is "+(d+1)+" "+m+" "+y);
}
}

public void yesterday(int d,int m,int y){
if((d==1)&&(m==1)){
System.out.print("yesterday is"+" "+"31"+" "+"12"+" "+(y-1));
}
else if(d==1){
System.out.print("yesterday is"+" "+(daysinthemonth((m-1),y))+" "+(m-1)+" "+y);
}
else{
System.out.print("yesterday is"+" "+(d-1)+" "+m+" "+y);
}
}


public static void main(String[] a){
Scanner input=new Scanner(System.in);
int m,y,n,d;
System.out.println("year");
y=input.nextInt();
System.out.println("month");
m=input.nextInt();
System.out.println("day");
d=input.nextInt();
date b=new date();


b.yesterday(d,m,y);
System.out.println();
System.out.println("today "+d+" "+m+" "+y);
b.tomorrow(d,m,y);

}
}