java interview Questions

Throw And Throws In Java throw: throw is used in re-throwing exception process or we can say that it is used to throw an exception object explicitly. It can take at most one argument which will be an exception object. Only unchecked exception can be thrown. throws: throws keyword is used to throw an exception object implicitly. The throws keyword is used with the method signature. We can declare more than one type of exceptions with method signature which should be comma separated. Note: 1.     throws is commonly used to throw checked exception. 2.     If we are calling a method that declares an exception then we must have to either caught or declare the exception. 3.     Exception can be re-thrown. https://cjavapoint.blogspot.com/?m=1

Static Blank Final Variable In Java In java, static blank final variable is a variable which is declared with final keyword but not initialised at declaration time. It can only be initialised in static block. https://cjavapoint.blogspot.com/?m=1

import java.util.Scanner;   import java.lang.Math;   public class ArmstsrongNumberExample   {   //function to check if the number is Armstrong or not   static boolean isArmstrong(int n)    {    int temp, digits=0, last=0, sum=0;    //assigning n into a temp variable   temp=n;    //loop execute until the condition becomes false   while(temp>0)     {    temp = temp/10;    digits++;    }    temp = n;    while(temp>0)    {    //determines the last digit from the number       last = temp % 10;    //calculates the power of a number up to digit times and add the resultant to the sum variable   sum +=  (Math.pow(last, digits));    //removes the last digit    temp = temp/10;    }   //compares the sum with n   if(n==sum)    //returns if sum and n are equal   return true;       //returns false if sum and n are not equal   else return false;    }    //driver code   public static void main(String args[])      {      int num;    Scanner sc= new Scanner(System.in);   System.out.print("Enter the limit: ");   //reads the limit from the user   num=sc.nextInt();   System.out.println("Armstrong Number up to "+ num + " are: ");   for(int i=0; i<=num; i++)   //function calling   if(isArmstrong(i))   //prints the armstrong numbers   System.out.print(i+ ", ");   }    }   https://cjavapoint.blogspot.com/?m=1

11 = 1 2: 21 = 2 3: 31 = 3 153: 13 + 53 + 33 = 1 + 125+ 27 = 153 125: 13 + 23 + 53 = 1 + 8 + 125 = 134 (Not an Armstrong Number)

Armstrong Number in Java In this section, we will discuss what is Armstrong number and also create Java programs to check if the given number is an Armstrong number or not. The Armstrong number program frequently asked in Java coding interviews and academics. Armstrong Number An Armstrong number is a positive m-digit number that is equal to the sum of the mth powers of their digits. It is also known as pluperfect, or Plus Perfect, or Narcissistic number. It is an OEIS sequence A005188. Let’s understand it through an example. https://cjavapoint.blogspot.com/?m=1