为什么在Java代码中会出现DivideByZeroException？

Question

import java.io.IOException;
import java.util.*;

public class calling {
public static String s;
public static String t;
public static int y;
public static int x;

public static int num1() {
int x;
Scanner scanner = new Scanner (System.in);
System.out.println("Please enter a number called x: ");
x=scanner.nextInt();
return x;    
}

public static int num2() {
int y;
Scanner scanner = new Scanner (System.in);
System.out.println("Please enter a second number called y: ");
y=scanner.nextInt();
return y;    
}

public static void calculation() {
Scanner input = new Scanner(System.in);

System.out.println("What process would you like to do? *, /, + or - ?");
s=input.next();

if (s.equals("*")) {
System.out.println("\nThe product of these numbers is:" + (x*y));}
else 
if (s.equals("+")) {
System.out.println("\nThe sum of these numbers is: " + (x+y));}

System.out.println("\nDo you want x or y to be the dividor/subtractor?: ");
t=input.next();

if (t.equals("y") || t.equals("Y") ) {

if (s.equals("/")) {
System.out.println("\nThe quotient of these numbers is:  " + (x/y));}
else 
if (s.equals("-")) {
System.out.println("\nThe difference of these numbers is: " + (x-y));}}

else 
if (t.equals("x") || t.equals("X")){

if (s.equals("/")) {
System.out.println("\nThe quotient of these numbers is: " + (y/x));}
else 
if (s.equals("-")) {
System.out.println("\nThe difference of these numbers is: " + ((y-x)));}}
}

public static void  main (String [] args) throws IOException {


num1();
num2();
calculation();


}

}

我一直在得到这个错误，这应该是我的最终结果，这只是正在进行的计算的结果

这是错误：“线程“main”java.lang.arithmetricException中的异常：/by零 打电话的时候。计算（calling.java:44） 打电话的时候。main（calling.java:64）”