{"id":1305,"date":"2021-11-04T19:08:36","date_gmt":"2021-11-04T19:08:36","guid":{"rendered":"https:\/\/rahulshettyacademy.com\/blog\/?p=1305"},"modified":"2021-11-30T18:51:53","modified_gmt":"2021-11-30T18:51:53","slug":"sdet-interview-questions-part-5","status":"publish","type":"post","link":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/2021\/11\/04\/sdet-interview-questions-part-5\/","title":{"rendered":"Sr.QA and SDET Interview Questions in Java – Part 5"},"content":{"rendered":"

1. Write a program to sort ArrayList using Comparable and Comparator<\/a><\/h3>\n

Solution: Sort ArrayList using Comparable<\/strong><\/p>\n

import java.util.ArrayList;<\/span><\/p>\n

import java.util.Collections;<\/span><\/p>\n

\/\/Using Comparable<\/span><\/p>\n

class Employee implements Comparable<Employee> {<\/span><\/p>\n

     private String name;<\/span><\/p>\n

     private int empId;<\/span><\/p>\n

     private int age;<\/span><\/p>\n

   <\/span><\/p>\n

     public Employee(String name, int empId, int age) {<\/span><\/p>\n

           this.name= name;<\/span><\/p>\n

           this.empId=empId;<\/span><\/p>\n

           this.age=age;<\/span><\/p>\n

     }<\/span><\/p>\n

     <\/span><\/p>\n

    @Override<\/span><\/p>\n

    public int compareTo(Employee employee) {<\/span><\/p>\n

           return this.age – employee.age;<\/span><\/p>\n

    }<\/span><\/p>\n

   <\/span><\/p>\n

    @Override<\/span><\/p>\n

    public String toString() {<\/span><\/p>\n

           return “[ Name= ” + name + “, Employee Id = ” + empId + “, Employee age = ” + age + “]”;<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

class Main {<\/span><\/p>\n

    public static void main(String[] args) {<\/span><\/p>\n

          ArrayList<Employee> list = new ArrayList<Employee>();<\/span><\/p>\n

          list.add(new Employee(“Rahul”,6589586,35));<\/span><\/p>\n

          list.add(new Employee(“John”,854756,30));<\/span><\/p>\n

          list.add(new Employee(“Robin”,784125,32));<\/span><\/p>\n

         <\/span><\/p>\n

           Collections.sort(list);<\/span><\/p>\n

           for(Employee e: list){<\/span><\/p>\n

                      System.out.println(e);<\/span><\/p>\n

             }<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

[ Name= John, Employee Id = 854756, Employee age = 30]<\/span><\/p>\n

[ Name= Robin, Employee Id = 784125, Employee age = 32]<\/span><\/p>\n

[ Name= Rahul, Employee Id = 6589586, Employee age = 35]<\/span><\/p>\n

Solution: Sort ArrayList using Comparator<\/strong><\/p>\n

import java.util.ArrayList;<\/span><\/p>\n

import java.util.Collections;<\/span><\/p>\n

import java.util.Comparator;<\/span><\/p>\n

\/\/Using Comparator<\/span><\/p>\n

class Employee {<\/span><\/p>\n

    private String name;<\/span><\/p>\n

    private int empId;<\/span><\/p>\n

    private int age;<\/span><\/p>\n

    public Employee(String name, int empId, int age) {<\/span><\/p>\n

          this.name = name;<\/span><\/p>\n

          this.empId = empId;<\/span><\/p>\n

          this.age = age;<\/span><\/p>\n

    }<\/span><\/p>\n

    public String getName() {<\/span><\/p>\n

          return this.name;<\/span><\/p>\n

    }<\/span><\/p>\n

    public int getEmpId() {<\/span><\/p>\n

          return this.empId;<\/span><\/p>\n

    }<\/span><\/p>\n

    public int getAge() {<\/span><\/p>\n

          return this.age;<\/span><\/p>\n

    }<\/span><\/p>\n

    public static Comparator<Employee> EmployeeNameComparator = new Comparator<Employee>() {<\/span><\/p>\n

          public int compare(Employee e1, Employee e2) {<\/span><\/p>\n

                String empName1 = e1.getName().toLowerCase();<\/span><\/p>\n

                String empName2 = e2.getName().toLowerCase();<\/span><\/p>\n

                return empName1.compareTo(empName2);<\/span><\/p>\n

          }<\/span><\/p>\n

    };<\/span><\/p>\n

    public static Comparator<Employee> EmployeeAgeComparator = new Comparator<Employee>() {<\/span><\/p>\n

          public int compare(Employee e1, Employee e2) {<\/span><\/p>\n

                int empAge1 = e1.getAge();<\/span><\/p>\n

                int empAge2 = e2.getAge();<\/span><\/p>\n

                return empAge1 – empAge2;<\/span><\/p>\n

          }<\/span><\/p>\n

    };<\/span><\/p>\n

    @Override<\/span><\/p>\n

    public String toString() {<\/span><\/p>\n

          return “[ Name= ” + name + “, Employee Id = ” + empId + “, Employee age = ” + age + “]”;<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

class Main {<\/span><\/p>\n

    public static void main(String[] args) {<\/span><\/p>\n

          ArrayList<Employee> list = new ArrayList<Employee>();<\/span><\/p>\n

          list.add(new Employee(“Rahul”, 6589586, 35));<\/span><\/p>\n

          list.add(new Employee(“John”, 854756, 32));<\/span><\/p>\n

          list.add(new Employee(“Lukas”, 784125, 30));<\/span><\/p>\n

          System.out.println(“Sort Employee List by Name”);<\/span><\/p>\n

          Collections.sort(list, Employee.EmployeeNameComparator);<\/span><\/p>\n

          for (Employee e : list) {<\/span><\/p>\n

                System.out.println(e);<\/span><\/p>\n

          }<\/span><\/p>\n

          System.out.println(“nSort Employee List by Age”);<\/span><\/p>\n

          Collections.sort(list, Employee.EmployeeAgeComparator);<\/span><\/p>\n

          for (Employee e : list) {<\/span><\/p>\n

                System.out.println(e);<\/span><\/p>\n

          }<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

Sort Employee List by Name<\/span><\/p>\n

[ Name= John, Employee Id = 854756, Employee age = 32]<\/span><\/p>\n

[ Name= Lukas, Employee Id = 784125, Employee age = 30]<\/span><\/p>\n

[ Name= Rahul, Employee Id = 6589586, Employee age = 35]<\/span><\/p>\n

Sort Employee List by Age<\/span><\/p>\n

[ Name= Lukas, Employee Id = 784125, Employee age = 30]<\/span><\/p>\n

[ Name= John, Employee Id = 854756, Employee age = 32]<\/span><\/p>\n

[ Name= Rahul, Employee Id = 6589586, Employee age = 35]<\/span><\/p>\n

2. I have arrayList like [Test1, Test2, Test3, Test4, Test5]<\/em> Write a Program to replace the “Test2” with string “ReplacedTest”<\/a><\/h3>\n

Solution:<\/strong><\/p>\n

import java.util.ArrayList;<\/span><\/p>\n

class Main {<\/span><\/p>\n

    public static void main(String[] args) {<\/span><\/p>\n

          ArrayList<String>  list = new ArrayList<String>();<\/span><\/p>\n

          list.add(“Test1”);<\/span><\/p>\n

          list.add(“Test1”);<\/span><\/p>\n

          list.add(“Test2”);<\/span><\/p>\n

          list.add(“Test3”);<\/span><\/p>\n

          list.add(“Test4”);<\/span><\/p>\n

         <\/span><\/p>\n

          System.out.println(“ArrayList before Replace”);<\/span><\/p>\n

          System.out.println(list);<\/span><\/p>\n

         <\/span><\/p>\n

          int index = list.indexOf(“Test2”);<\/span><\/p>\n

          list.set(index,”ReplacedTest”);<\/span><\/p>\n

         <\/span><\/p>\n

          System.out.println(“nArrayList after Replace”);<\/span><\/p>\n

          System.out.println(list);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

ArrayList before Replace<\/span><\/p>\n

[Test1, Test1, Test2, Test3, Test4]<\/span><\/p>\n

ArrayList after Replace<\/span><\/p>\n

[Test1, Test1, ReplacedTest, Test3, Test4]<\/span><\/p>\n

3. Write a Java program to insert the specified element at the end of a linked list<\/a><\/h3>\n

Solution:<\/strong><\/p>\n

import java.util.LinkedList;<\/span><\/p>\n

class Main {<\/span><\/p>\n

    public static void main(String[] args) {<\/span><\/p>\n

          LinkedList<String>  list = new LinkedList<String>();<\/span><\/p>\n

          list.add(“Test1”);<\/span><\/p>\n

          list.add(“Test1”);<\/span><\/p>\n

          list.add(“Test2”);<\/span><\/p>\n

          list.add(“Test3”);<\/span><\/p>\n

          list.add(“Test4”);<\/span><\/p>\n

         <\/span><\/p>\n

          System.out.println(“LinkedList before Inserting Element at the End\/Last”);<\/span><\/p>\n

          System.out.println(list);<\/span><\/p>\n

         <\/span><\/p>\n

          list.offerLast(“LastInsertedElement”);<\/span><\/p>\n

         <\/span><\/p>\n

          System.out.println(“nLinkedList after Inserting Element at the End\/Last”);<\/span><\/p>\n

          System.out.println(list);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

LinkedList before Inserting Element at the End\/Last<\/span><\/p>\n

[Test1, Test1, Test2, Test3, Test4]<\/span><\/p>\n

LinkedList after Inserting Element at the End\/Last<\/span><\/p>\n

[Test1, Test1, Test2, Test3, Test4, LastInsertedElement]<\/span><\/p>\n

4. Write a program to perform Pairwise swap elements of a given linked list<\/a><\/h3>\n

In Pairwise swapping each pair will be swapped<\/p>\n

Example:<\/strong><\/p>\n

Input  1 > 2 > 3 > 4 > 5<\/p>\n

Output 2 > 1 > 4 > 3 > 5<\/p>\n

Solution:<\/strong><\/p>\n

\/\/Pairwise Swap<\/span><\/p>\n

public class LinkedList {<\/span><\/p>\n

    Node head;<\/span><\/p>\n

    class Node {<\/span><\/p>\n

          int data;<\/span><\/p>\n

          Node next;<\/span><\/p>\n

          Node(int d)<\/span><\/p>\n

          {<\/span><\/p>\n

                data = d;<\/span><\/p>\n

                next = null;<\/span><\/p>\n

          }<\/span><\/p>\n

    }<\/span><\/p>\n

    void pairWiseSwap()<\/span><\/p>\n

    {<\/span><\/p>\n

          Node temp = head;<\/span><\/p>\n

          while (temp != null && temp.next != null) {<\/span><\/p>\n

                int k = temp.data;<\/span><\/p>\n

                temp.data = temp.next.data;<\/span><\/p>\n

                temp.next.data = k;<\/span><\/p>\n

                temp = temp.next.next;<\/span><\/p>\n

          }<\/span><\/p>\n

    }<\/span><\/p>\n

    public void push(int new_data)<\/span><\/p>\n

    {<\/span><\/p>\n

          Node new_node = new Node(new_data);<\/span><\/p>\n

          new_node.next = head;<\/span><\/p>\n

          head = new_node;<\/span><\/p>\n

    }<\/span><\/p>\n

    void print()<\/span><\/p>\n

    {<\/span><\/p>\n

          Node temp = head;<\/span><\/p>\n

          while (temp != null) {<\/span><\/p>\n

                System.out.print(temp.data + ” “);<\/span><\/p>\n

                temp = temp.next;<\/span><\/p>\n

          }<\/span><\/p>\n

          System.out.println();<\/span><\/p>\n

    }<\/span><\/p>\n

    public static void main(String args[])<\/span><\/p>\n

    {<\/span><\/p>\n

          LinkedList list = new LinkedList();<\/span><\/p>\n

          list.push(5);<\/span><\/p>\n

          list.push(4);<\/span><\/p>\n

          list.push(3);<\/span><\/p>\n

          list.push(2);<\/span><\/p>\n

          list.push(1);<\/span><\/p>\n

          System.out.println(“Linked List before PairWise Swap “);<\/span><\/p>\n

          list.print();<\/span><\/p>\n

          list.pairWiseSwap();<\/span><\/p>\n

          System.out.println(“Linked List after PairWise Swap”);<\/span><\/p>\n

          list.print();<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

Linked List before PairWise Swap<\/span><\/p>\n

1 2 3 4 5<\/span><\/p>\n

Linked List after PairWise Swap<\/span><\/p>\n

2 1 4 3 5<\/span><\/p>\n

5. Check if two arrays have same number of items and values<\/a><\/h3>\n

Consider I have two arrays<\/a><\/p>\n

a = [1,2,3,4]<\/p>\n

b = [2,1,4,3]<\/p>\n

Considering the above array, We have the same Item in both the arrays, but the index is different<\/p>\n

Write a program to check a is having the same number of items and same values compared with b<\/p>\n

You should not use Arrays.Equals() method<\/p>\n

<\/strong><\/p>\n

Solution:<\/strong><\/p>\n

There are two requirements here<\/p>\n

1. Number of Elements in a[] should be same as b[] \/\/a.length == b.length<\/p>\n

2. Both a[] and b[] should have the same element, order sequence can be different<\/p>\n

3. You should not use Arrays.Equals method<\/p>\n

import java.util.Arrays;<\/span><\/p>\n

public class Main {<\/span><\/p>\n

    public static void main(String args[]) {<\/span><\/p>\n

          int[] array1 = { 1, 2, 3, 4 };<\/span><\/p>\n

          int[] array2 = { 2, 1, 4, 3 };<\/span><\/p>\n

          boolean b = false;<\/span><\/p>\n

          if (array1.length != array2.length) {<\/span><\/p>\n

                 b = false;<\/span><\/p>\n

          } else {<\/span><\/p>\n

                Arrays.sort(array1);<\/span><\/p>\n

                Arrays.sort(array2);<\/span><\/p>\n

                for(int i=0;i<array1.length;i++) {<\/span><\/p>\n

                      if(array1[i]!=array2[i]) {<\/span><\/p>\n

                            b=false;<\/span><\/p>\n

                            break;<\/span><\/p>\n

                      }<\/span><\/p>\n

                      b=true;<\/span><\/p>\n

                }<\/span><\/p>\n

          }<\/span><\/p>\n

          if (b)<\/span><\/p>\n

                System.out.println(“Arrays are having same values”);<\/span><\/p>\n

          else<\/span><\/p>\n

                System.out.println(“Arrays are not having same values”);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

Arrays are having same values<\/span><\/p>\n

6. Write a Java Program to find the largest and smallest word in a string<\/a><\/h3>\n

Solution:<\/strong><\/p>\n

public class Main {<\/span><\/p>\n

     public static void main(String[] args){<\/span><\/p>\n

           String string = “Rahul Shetty Academy is the best”;<\/span><\/p>\n

           String[] words = string.trim().replaceAll(“\\s+”, ” “).split(” “);<\/span><\/p>\n

              String shortest = words[0];<\/span><\/p>\n

              String longest =  words[0];<\/span><\/p>\n

              for(String word : words){<\/span><\/p>\n

                if(word.length() < shortest.length()){<\/span><\/p>\n

                      shortest = word;<\/span><\/p>\n

                  }<\/span><\/p>\n

                if(word.length() > longest.length()){<\/span><\/p>\n

                      longest = word;<\/span><\/p>\n

                  }<\/span><\/p>\n

              }<\/span><\/p>\n

              System.out.println(“The Shortest Word = “+shortest);  <\/span><\/p>\n

              System.out.println(“The Longest Word = “+ longest);<\/span><\/p>\n

      } <\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

The Shortest Word = is<\/span><\/p>\n

The Longest Word = Academy<\/span><\/p>\n

7. Java Program to Check if a Given Number is Perfect Square<\/a><\/h3>\n

A perfect square is a positive integer, it is the product of the number itself<\/p>\n

Example:<\/strong><\/p>\n

49 = 7*7, So the 49 is Perfect Square<\/p>\n

Solution:<\/strong><\/p>\n

class Main {<\/span><\/p>\n

    static boolean isPerfectSquare(int x)<\/span><\/p>\n

    {<\/span><\/p>\n

          if (x >= 0) {<\/span><\/p>\n

                int sqrt = (int)Math.sqrt(x);<\/span><\/p>\n

                return ((sqrt*sqrt) == x);<\/span><\/p>\n

          }<\/span><\/p>\n

          return false;<\/span><\/p>\n

    }<\/span><\/p>\n

    public static void main(String[] args)<\/span><\/p>\n

    {<\/span><\/p>\n

          int x = 8100;<\/span><\/p>\n

          if (isPerfectSquare(x))<\/span><\/p>\n

                System.out.print(“Given Number is a Perfect Square”);<\/span><\/p>\n

          else<\/span><\/p>\n

                System.out.print(“Given Number is Not a Perfect Square”);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

Given Number is a Perfect Square<\/span><\/p>\n

8. Write a Program to cover all major concepts of OOPs<\/a><\/h3>\n

Note: There are multiple ways to write this program, we have shown one way.<\/em><\/p>\n

Solution:<\/strong><\/p>\n

\/\/Abstraction<\/span><\/p>\n

interface Car {<\/span><\/p>\n

    void printName();<\/span><\/p>\n

}<\/span><\/p>\n

\/\/Inheritance<\/span><\/p>\n

class Ford {<\/span><\/p>\n

    private String name; \/\/Encapsulation<\/span><\/p>\n

    public String getName() {<\/span><\/p>\n

          return name;<\/span><\/p>\n

    }<\/span><\/p>\n

    public void setName(String newName) {<\/span><\/p>\n

          name = newName;<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

class OneMore extends Ford implements Car{<\/span><\/p>\n

    @Override \/\/Overriding<\/span><\/p>\n

    public void printName() {<\/span><\/p>\n

          System.out.println(“Override Method Print ” + super.getName());<\/span><\/p>\n

         <\/span><\/p>\n

    }<\/span><\/p>\n

    \/\/Overloading<\/span><\/p>\n

    public void printName(String string) {<\/span><\/p>\n

          System.out.println(“Overloaded Method Print ” + string);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

class Main {<\/span><\/p>\n

    public static void main(String[] args) {<\/span><\/p>\n

          OneMore object = new OneMore();<\/span><\/p>\n

          object.setName(“Eco Sport”);<\/span><\/p>\n

          object.printName();<\/span><\/p>\n

          object.printName(“Aspire”);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

Overloading Print Eco Sport<\/span><\/p>\n

Overloading Print Aspire<\/span><\/p>\n

9. Write a program to find the length of the string without using string.length();<\/a><\/h3>\n

Note: There are multiple ways to write this program, we have shown one way.<\/em><\/p>\n

<\/em><\/p>\n

Solution:<\/strong><\/p>\n

public class Main<\/span><\/p>\n

{<\/span><\/p>\n

    static int i,c,res;<\/span><\/p>\n

    static void length(String s)<\/span><\/p>\n

    {<\/span><\/p>\n

        try<\/span><\/p>\n

        {<\/span><\/p>\n

            for(i=0,c=0;0<=i;i++,c++)<\/span><\/p>\n

            s.charAt(i);<\/span><\/p>\n

        }<\/span><\/p>\n

        catch(StringIndexOutOfBoundsException e)<\/span><\/p>\n

        {<\/span><\/p>\n

          System.out.println(“”);<\/span><\/p>\n

            System.out.print(“The length of the string “”+s+”” is ” +c);<\/span><\/p>\n

        }<\/span><\/p>\n

    }<\/span><\/p>\n

   <\/span><\/p>\n

    public static void main (String args[])<\/span><\/p>\n

    {<\/span><\/p>\n

        String string = “Rahul Shetty Academy”;<\/span><\/p>\n

        length(string);<\/span><\/p>\n

    }<\/span><\/p>\n

}<\/span><\/p>\n

Output:<\/span><\/p>\n

The length of the string “Rahul Shetty Academy” is 20<\/span><\/p>\n

Course Alert<\/span><\/em><\/h5>\n

If you are interested in landing a SDET or Sr. QA Automation Engineer role, check out our popular SDET course to learn the fundamental skills required an SDET needs to perform at work. Also, I have another popular course which covers Top 150+ Interview questions most commonly asked in SDET \/ Automation interviews.<\/strong><\/p>\n