How to catch exceptions in Java

Hi
My name is Raj and joined this forum recently. I have just started to learn Java Programming. I was interested in adding error handling mechanism to my program whose code is written below. The programs runs fine but if someone enter a character instead of integer program end with some error message. Kindly someone put the code of error mechanism in my program code as an illustration-

Code java:

import java.util.Scanner;
 
public class Calci
{ 
 
 public static void main(String args[])
 {
  for(;;)
  {
   int choice;
   Scanner in = new Scanner(System.in);
   System.out.println("*****************MENU***********************");
   System.out.println("1.Add Numbers " + "      2.Substract Numbers");
   System.out.println("3.Multiply numbers " + " 4.Divide Numbers");
   System.out.println("*************Press '5' to Exit**************");
   System.out.println(" Enter your menu Choice");
   choice=in.nextInt();
 
 
   switch(choice)
   {
    case 1:
    int addr,addl,sum=0;
    System.out.println("How many nos you want to add");
    addr=in.nextInt();
    int a[]=new int[addr];
    System.out.println("Enter " + addr + " numbers");
    for(addl=0;addl<addr;addl++)
    {
     a[addl]=in.nextInt();
     sum = sum + a[addl];
     System.out.println("The sum of Numbers is: " + sum);
    }
    break;
 
    case 2:
    int sub2,sub1,subl;
    System.out.println("Enter the 1st number");
    sub1=in.nextInt();
    System.out.println("How many numbers you want to substract from 1st number");
    sub2=in.nextInt();
    int s[]=new int[sub2];
    System.out.println("Enter " + sub2 + " numbers");
    for(subl=0;subl<sub2;subl++)
    {
     s[subl]=in.nextInt();
     sub1 = sub1 - s[subl];
     System.out.println("The result of subtraction is: " + sub1);
    }
    break; 
 
    case 3:
    int mloop, mul,mresult=1;
    System.out.println("How many nos you want to multiply");
    mul=in.nextInt();
    int m[]=new int[mul];
    System.out.println("Enter " + mul + " numbers");
    for(mloop=0;mloop<mul;mloop++)
    {
     m[mloop]=in.nextInt();
     mresult=mresult*m[mloop];
     System.out.println("The result of multiplication is: " + mresult);
    }
    break;
 
    case 4:
    int div1,div2,divloop;
    System.out.println("Enter the dividend");
    div1=in.nextInt();
    System.out.println("How many times you want to divide the divisor");
    div2=in.nextInt();
    int d[]=new int[div2];
    System.out.println("Enter " + div2 + " divisors");
    for(divloop=0;divloop<div2;divloop++)
    {
     d[divloop]=in.nextInt();
     div1=div1/d[divloop];
     System.out.println("The result of division is: " + div1);
    }
    break;
 
    default:
    System.out.println("Wrong Choice");
    System.exit(0);
    }
   }
  }
}