In today’s competitive job market, landing a programming job requires more than just technical skills. Interviewers often delve into the depths of programming languages to assess a candidate’s expertise. Whether you’re a seasoned developer or a fresh graduate, having a solid grasp of the most common programming language questions and answers can give you an edge. In this article, we’ll explore the frequently asked programming language questions in interviews and provide comprehensive answers to help you ace your next interview.
As the tech industry continues to evolve, programming languages remain at the core of software development. Interviews are a critical juncture where employers assess candidates’ abilities to solve problems, write efficient code, and communicate effectively. Let’s delve into the significance of programming language questions in interviews and explore some of the most commonly asked questions.
Importance of Programming Language Questions in Interviews
In interviews, programming language questions serve multiple purposes. They assess your technical prowess, problem-solving skills, and familiarity with industry-standard languages. Moreover, they offer insight into your approach to coding challenges and your ability to adapt to different programming paradigms.
Write a Program to Reverse a String ?
Visit Program Page to get this program.
What is mean by OPPS ?
OOPS is Object Oriented Programming Structure. OOPS is a method of implementation in which programs are organized as collection of objects, class and methods.
What is mean Class & Method ,Object ?
Class
Class is a collection of objects and methods • Class contains attributes(variables and methods) that are common to all the objects created in a class. Method
Method defines the set of action to be performed. Object
Object is the run time memory allocation. • Using object we call any methods.
What is mean by Encapsulation ?
It is the structure of creating folders.It wraps the data and code acting on data together in to a single unit. Ex: encapsulation is POJO class. It is otherwise called Data hiding.
Method overriding is used to provide the specific implementation of the method that is already provided by its super class. Method overloading is performed within class. Method overriding occurs in two classes that have IS-A (inheritance) relationship. In case of method overloading, parameter must be different.
What is mean by polymorphism ?
Poly-many-Morphism-forms. Taking more than one forms is called polymorphism or one task implemented in many ways.
What is mean by inheritance ?
Accessing one class Properties in another class without multiple object creation. It avoids time and memory wastage. • It ensures code reusability.
What are the ways to access the methods /data from another class ?
We can access the another class methods either by creating object or using extends keyword.
What is mean by access specifier ?
It defines the scope or level of access for variables,methods and classes
What are the difference between public and protected ?
Public: It is global level access( same package + different package). Protected: can access Inside package ( object creation + extends )
What is mean by Abstraction ?
Hiding the implementation part or business logic is called abstraction.
What are the types of Abstraction ?
Partially abstraction(using abstract class).
Fully abstraction(using interface).
Can we create Object for Abstract class ?
No, we cant create object for abstract class.
What is mean by Interface ?
It will support only abstract method(without business logic), won’t support non abstract method(method with business logic ) In interface “public abstract” is default. using “implements” keyword we can implement the interface in a class where we can write the business logic for all unimplemented methods.
What are the difference between Abstract and Interface ?
Abstract class: Using Abstract class,we can acheive partial abstraction. • It support both abstract method and non-abstract method. • using “extends” keyword you can inherit an abstract class. • For any abstract method we need to mention “public abstract”.
Interface: Using interface,we can acheive full abstraction. • It supports only abstract method. • It is using “implements” keyword. • “public Abstract” is default, no need to mention it explicitly.
What is mean by String?
• Collection of characters or words enclosed within double quotes is called as String. • String is a class in java • String is index based • Example : “greenstechnology”.
Automation testing has become an integral part of software development and quality assurance processes. As companies seek to enhance their efficiency and reliability, the demand for skilled automation testers has soared. If you’re preparing for an automation testing interview, you’ve come to the right place. In this article, we’ll cover a range of commonly asked interview questions and provide insightful answers to help you succeed. Let’s dive into the world of automation testing!
Introduction to Automation Testing
Automation testing involves using specialized software tools to automate the execution of test cases. It reduces manual effort, accelerates testing cycles, and enhances accuracy. Automation testers write scripts to simulate user interactions with applications and validate their behavior.
Benefits of Automation Testing
Automation testing offers numerous advantages, including faster execution, broader test coverage, and consistent results. It’s particularly beneficial for repetitive tasks and regression testing.
Common Automation Testing Tools
There are several popular automation testing tools available, such as Selenium, Appium, and JUnit. Each tool has its strengths and is suited for different types of testing.
Technical Questions for Automation Testers
1. How much you rate yourself in selenium out of 5?
Out of 5 I will rate myself 3.5 in selenium.
2. Which locator you are using in your framework and why?
Mostly we used ID and Xpath because Id is the fastest and unique one and after that we prefer Xpath. Anyways we have other locators as well like css , class name, tag name, Link text, Partial Link text.
3. What is the difference between findelement & findelements?
findelement will give the first appearance of that element which matches our locator, whereas findelements will give us list of all the elements which is present over the webpage and matching our locator. And if we don’t find the element findelement will give us nosuchelementexception whereas findelements will return NULL/Empty list.
4. Can you tell me how you will handle multiple window in selenium?
We have windowhandle & windowhandles function for handling Multiple windows. Windowhandle will give the string value of only the active window that is open whereas windowhandles will give set of all the windows that are open in browser.
5. How you will move from one window to another?
First we will check what all windows are open by using driver.getwindowhandles, to get set of opened windows , then I use iterator to iterate over each of the pages and inside for loop will check like Current URL matches with the excepted page, if match then switch to that window by using driver.switchTo(Destination window) -> to return back to main parent window use driver.defaultwindow.
6. Tell me the difference between Implicit & Explicit wait?
Implicit wait applies for all the elements and all the tests like if we give 10 sec of implicit wait it will wait for 10 sec for each element before giving nosuchelement exceptions. While Explicit wait can be applied for any particular step for which you want extra wait time so we can use explicit wait. We can use mix of both waits to depend on the situation of the step.
8. Can you tell me about StaleElementReferenceException?
Stale means old or decayed, here it sounds like element which was present on that page is no longer there or decayed. To handle this, we can refresh the webpage before pointing to that element. We can write script for waiting via explicit wait by writing expected condition.refresh. Or we can go with page object model in that we can over come this stale element exception.
9.What do you mean by User Defined Exception?
User Defined Exception or custom exception is creating your own exception class and throws that exception using ‘throw’ keyword. This can be done by extending the class Exception. … The keyword “throw” is used to create a new Exception and throw it to the catch block.
10.Can you tell me what is assert in TestNG?
Assert is like verification where we check like expected thing and actual thing are same or not.
11. Which assert you have used in TestNg?
We have used Hard assert and Soft assert, while applying Hard assert if we found any glitch in expected and actual then it will through exception and move to next @test while Soft assert it won’t give exception and move to next step of that test. And to get all the exceptions in console we need to write at the end assert.all.
12.Can you tell me about the order of TestNG annotations?
13.Do you heard about Priority in TestNg can we set -ve priority?
Yes, like priority is 0, -1, TestNg will run -1 then 0 then 1. And if we have any @test which is not having any priority set, then in that case it will search via alphabetic order whichever comes first and execute test respectively.
14. Do you work in cucumber, can you tell me what all files required in cucumber?
In cucumber we have Feature file, Step Definition file and Test Runner file. In feature file we used to write scenario in gherkin language which is most like in plain English language. Here we use some of the keywords like feature, scenario, scenario outline, given, when, then, and, example, background keywords for writing our test scenarios steps In Step Definition file we write mapping code for all the scenario of feature file. In test Runner file we provide the address of the feature file, step definition file, and all-important Tags, Plugin, Listeners in that.
15. What is the difference between scenario & scenario outline?
When we have single scenario and we need to run it one time at that place we use Scenario. If you want some parametrization or Data Driven testing at that time, we can use scenario outline where we have to use Example keyword like if we are running this scenario for 3 different data set like username & pass. so, it will run 3 times.
16. Can you tell me more about Background Keyword? Background is used when we have some common Given part. Suppose we have pre-condition that we have to check this before each scenario. so in order to avoid rewriting same step we can write it in Background.
17.What is the use of Dry Run in cucumber? Dry run is not running our whole application it will check whether all features are mapped with Step definition.
18.What is hooks in cucumber?
In cucumber we use hooks for common functionalities, hooks are like we want to run before & after each of the scenario. In hooks we have 2 different @before, @ after which run before and after of each scenario. Also @beforestep, @afterstep which run before and after each step
19. Can you tell me how you will re-run failed scenario in cucumber?
For that we can use re-run attribute in our test runner file. After that we can write one file location. Where all the test cases which failed while execution get stored. So next time while running execution we can give this file location and run the failed TC.
20.You have worked in Cucumber & TestNG according to you which one is best?
I will consider Cucumber as it is most likely understood by Laymen people which is English plain language. Because in order to understand the functionality flow no need to go look and script/code. Via Scenario steps lines only we can get clear understanding about the functionality. It helps to come all the QA members Dev, Client, Product Owner on same page.
21.Can you explain me TestNG?
TestNG is advanced version of Junit only. It is mainly used by Dev/QA for maintain the code easily and for unit testing. It provides lots of benefits to us like we can create a suite and we can write all the required Tc in one go only using that suite. We can group our Tc we can set priority we can run our tc in parallel mode, We can generate good reports via TestNG. We can write functionality depends on methods, depends on group. We can run single tc multiple time with single set of data of multiple set of Data.
22.How to run single method multiple time in TestNG?
We have invocation count attribute in @test annotiation. We can write invocation count as 3 if we want to run it 3 times. Apart from that we can write threadpull.size if we want to run that case in multiple thread.
23. Have you used GIT in your project can you explain about it?
Yes I have used GIT, It is a version control tool. Where we can maintain our central repo. we used to manage our code via GIT only. We use Git to maintain our project in our local system. So, if someone like to work on that project I need to send complete update copy to him and after that he can work on that. There are chances that single project is handled by multiple teams across the globe. So, it will be difficult if we won’t use GIT.
24.Can you give me some GIT commands which you used on daily basis?
Git status– which shows status of all the files,if we have some files which is not yet added to our repo so it will give us untracked file. After that we can use GIT add command after adding it will added to particular index and we can commit this file using Git Commit-(Message) we can commit this untracked file. Also we have Git Merge, Git Post, Git Pull, Git It in etc.
25. How to solve Merge conflict in GIT?
As we are only 2 tester working on this project, if we have any merge conflict I used to pull all the latest file/scripts to my local system. Then I will analyze the difference between that particular file and merge file. After that I will check with my team member whether all his imp things are covered then I will add my steps and push the script to the central repo.
26. What is the difference between Smoke & Sanity Testing?
Smoke and Sanity we can are like same thing because both are checking important functionality. Smoke testing is done on first stable build from developer to check like whether it is stable enough to move further or not. While Sanity testing is subset of regression test which we perform on stable build and here also we used to check all the imp functionality.
27. What is Agile ceremony?
We have 4 Agile ceremony -Sprint planning, Sprint review, Sprint Retrospective, Daily scrum meeting.
28. Explain Git workflow?
Step 1: Set up a Github Organization. … Step 2: Fork Organization Repository to Your Personal GitHub. … Step 3: Clone the Repository to Your Local Machine. … Step 4: Create a Branch for your Working Files. … Step 5: Set Remote Repository to the GitHub Organization. … Step 6: Get Coding! Step 7: Pull the Most Recent Files From the Organization Repo Step 8: Merge the Master Branch Into the Feature Branch Step 9: Push Your Code to your GitHub Repo Step 10: Make a Pull Request to the Organization Repo
29. Apart from sendkeys, are there any different ways, to type content onto the editable field?
Using Actions Class: Actions action = new Actions(driver); action. keyDown(Keys. …
Using SendKeys Chord: driver. findElement(By. …
Using Robot Class: // Create Robot class Robot rb = new Robot(); // Press control keyboard key rb.
31. What is dry run in Cucumber?
Dry-run is used to compile feature files and step definitions in cucumber. It is specially used in the stage when you will have to see if there are any compilation errors, to check that you can use dry-run. Dryrun options can either set as true or false.
32.Annotations in Cucumber Total 11 Annotations -Feature, Scenario, Background, given, when , then, and, but, example, scenario outline, scenario template.
33. How do you handle if XPath is changing dynamically?
Option 1: Look for any other attribute which Is not changing every time In that div node like name, class etc. So If this div node has class attribute then we can write xpath as bellow.
The finally block always executes when the try block exits. This ensures that the finally block is executed even if an unexpected exception occurs.
Conclusion
In the rapidly evolving landscape of software development, automation testing is a critical component of ensuring high-quality products. By mastering the concepts, tools, and best practices outlined in this article, you’ll be well-prepared to excel in automation testing interviews and contribute to the success of your projects.
Automation testing continues to evolve, and staying updated with the latest trends and technologies is essential for long-term success in this field. Good luck on your journey to becoming an automation testing expert!
Are you a budding programmer or a job seeker preparing for a Java automation interview? Don’t fret; we’ve got you covered! In this comprehensive guide, we’ll walk you through some essential questions and answers that will help you ace your beginner-level Java automation interview. So, let’s dive right in and equip you with the knowledge and confidence to impress your potential employers.
Introduction to Java Automation
Java automation refers to the process of utilizing Java programming language for automating various tasks, primarily in software testing and quality assurance. Automation has become a pivotal aspect of software development, enhancing efficiency and accuracy throughout the testing lifecycle.
Why is Java Used in Automation Testing?
Java’s widespread adoption in automation testing is attributed to its platform independence, robustness, and extensive libraries and frameworks. The Java Virtual Machine (JVM) enables seamless execution across different operating systems, making it an ideal choice for cross-platform testing.
Key Features of Java for Automation
Java boasts several features that make it a preferred language for automation:
Object-Oriented Nature: Java’s object-oriented paradigm promotes modular and organized code, simplifying maintenance and enhancing reusability.
Rich Standard Library: Java’s extensive library provides pre-built functions for common tasks, reducing development time.
Exception Handling: Java’s robust exception handling mechanism aids in creating stable and reliable automation scripts.
Community Support: Java’s large and active community ensures access to abundant resources, tutorials, and forums.
Setting Up the Java Development Environment
Before diving into Java automation, ensure you have a properly configured development environment. Follow these steps:
Download and install the latest Java Development Kit (JDK).
Set up a preferred Integrated Development Environment (IDE), such as Eclipse or IntelliJ IDEA.
Configure the Java environment variables for seamless compilation and execution.
Best Practices for Java Automation
Adopt these best practices for efficient and maintainable automation scripts:
Clear and Descriptive Variable and Method Names
Modular Code Structure
Regular Code Reviews and Refactoring
Continuous Integration and Continuous Deployment (CI/CD) Integration
Common Interview Questions and Answers
1. What is Static Method in JAVA ?
Direct calling, Calling by class name.
2. Can I access Static method by using object reference?
Yes we can, but we got one warning that you need to access it via Direct or By class name.
3. Can we overload & override main method?
Overload-Yes, Override-No
4. What do you mean by Static keyword in Java?
Static means it is at class level not at instance level, we have static method, static variable & static inner class. When we have any variable as static so it will remain same for all the instance of our classes, and static/Private/Final methods can’t be over-ridden like if we have initialized any method as Static so we cannot override it in any child class.
5. What do you mean by Exceptions in Java?
Exception is like any interruption in our normal flow. Like if we are running anything and we got issues in our script this is we called exception, we have 2 types of exception Run Time & Compile Time. (checked & Unchecked exceptions)
6. Can you tell me about difference between Throw and Throws keyword?
Throw is a keyword used inside a body of function. And Throws used while initializing any method. By using Throw we can throw only one exception while for Throws we can declare multiple exceptions which might occur in that particular function. Throws keyword followed by instance name and Throw keyword is followed by class name of that exception.
7. Which locator you are using in your framework and why?
Mostly we used ID and Xpath because Id is the fastest and unique one and after that we prefer Xpath. Anyways we have other locators as well like css , class name, tag name, Link text, Partial Link text.
8. What is Difference between list and set?
The main difference between List and Set is that Set is unordered and contains different elements, whereas the list is ordered and can contain the same elements in it.
9. What is Run time polymorphism?
Run-Time Polymorphism: Whenever an object is bound with the functionality at run time, this is known as runtime polymorphism. The runtime polymorphism can be achieved by method overriding. Java virtual machine determines the proper method to call at the runtime, not at the compile time.
10. Why the main method is static?
Java main() method is always static, so that compiler can call it without the creation of an object or before the creation of an object of the class. … Static method of a class can be called by using the class name only without creating an object of a class.
11. What is Method overloading and overriding?
Method overriding is used to provide the specific implementation of the method that is already provided by its super class. Method overloading is performed within class. Method overriding occurs in two classes that have IS-A (inheritance) relationship. In case of method overloading, parameter must be different.
12. What is Use of constructor?
The purpose of constructor is to initialize the object of a class while the purpose of a method is to perform a task by executing java code. Constructors cannot be abstract, final, static and synchronised while methods can be. Constructors do not have return types while methods do.
13. Difference between static and non-static methods?
Static method uses complie time binding or early binding. Non-static method uses run time binding or dynamic binding. A static method cannot be overridden being compile time binding. A non-static method can be overridden being dynamic binding.
14. Can we declare many interfaces object class inside the interface class ?
Yes, you can define a class inside an interface. In general, if the methods of the interface use this class and if we are not using it anywhere else we will declare a class within an interface.
15. What are Types of the assertion?
Selenium Assertions can be of three types: “assert”, “verify”, and ” waitFor”. When an “assert” fails, the test is aborted. When a “verify” fails, the test will continue execution, logging the failure. A “waitFor” command waits for some condition to become true.
16. What is Abstraction in java and exp?
In Page Object Model design pattern, we write locators (such as id, name, xpath etc.,) in a Page Class. We utilize these locators in tests but we can’t see these locators in the tests. Literally we hide the locators from the tests.
17. What is a super keyword in java?
The super keyword refers to superclass (parent) objects. It is used to call superclass methods, and to access the superclass constructor. The most common use of the super keyword is to eliminate the confusion between Superclasses and subclasses that have methods with the same name.
18. What is Difference between break and continue statement ?
Break statement resumes the control of the program to the end of loop and made executional flow outside that loop. Continue statement resumes the control of the program to the next iteration of that loop enclosing ‘continue’ and made executional flow inside the loop again.
19. What is Difference between Abstract class & interface?
Abstract class can inherit another class using extends keyword and implement an interface. Interface can inherit only an inteface. Abstract class can be inherited using extends keyword. Interface can only be implemented using implements keyword.
20. Have you used the action class and where it is used?
Using the Actions class in Selenium, we can implement the sendKeys() method to type specific values in the application. That is how you use the actions class in Selenium with sendKeys() method. … The perform() method is used to perform the series of actions that are defined.
21. What is the difference between checked and unchecked exceptions?
There are two types of exceptions: checked exception and unchecked exception. … The main difference between checked and unchecked exception is that the checked exceptions are checked at compile-time while unchecked exceptions are checked at runtime checked exceptions – SQLException,IOException,ClassNotFoundException,InvocationTargetException unchecked exceptions – NullPointerException,ArrayIndexOutOfBoundsException,ArithmeticException,IllegalArgumentException NumberFormatException
22. What is Difference between this and super?
this keyword mainly represents the current instance of a class. On other hand super keyword represents the current instance of a parent class. this keyword used to call default constructor of the same class.
23. What is the difference between length and length() in Java?
The length is an instance variable of an array in Java whereas length() is a method of String class
24. What is an abstract class?
Abstract Classes and Methods Abstract class: is a restricted class that cannot be used to create objects (to access it, it must be inherited from another class). Abstract method: can only be used in an abstract class, and it does not have a body. The body is provided by the subclass (inherited from).
25. What is Difference between Actions and Action?
Actions is a class that is based on a builder design pattern. This is a user-facing API for emulating complex user gestures. Whereas Action is an Interface which represents a single user-interaction action.
26. How many times you can write catch block?
maximum one catch block will be executed. No, we can write multiple catch block but only one is executed at a time.
27. What is Collection ?
Collection is called collection interface having methods which are common throughout all collections. it is basically a class from java.util package which contains some methods which we can use for collection objects . A collection represents a group of objects. Collection – 1. List, 2. Set, 3. Queue
28. What is ENCAPSULATION ?
Encapsulation is defined as the wrapping up of data under a single unit. It is the mechanism that binds together code and the data it manipulates. Encapsulation can be achieved by: Declaring all the variables in the class as private and writing public methods in the class to set and get the values of variables. All the classes in an Automation Framework are an example of Encapsulation. In Page Object Model classes, we declare the data members using @FindBy and initialization of data members will be done using Constructor to utilize those in methods.
29.What is POLYMORPHISM ?
Polymorphism allows us to perform a single action in different ways. In Java polymorphism can be achieved by two ways:
Method Overloading: When there are multiple methods with same name but different parameters then these methods are said to be overloaded. Methods can be overloaded by change in number of arguments or/and change in type of arguments. In Selenium Automation, Implicit wait is an example of Method Overloading. In Implicit wait we use different time stamps such as SECONDS, MINUTES, HOURS etc.
Method Overriding: It occurs when a derived class has a definition for one of the member functions of the base class. That base function is said to be overridden. In Selenium Automation, Method Overriding can be achieved by overriding any WebDriver method. For example, we can override the findElement method In assertion we have used overload because in assertion we used to like asset.true(actual, expected) and second time we can use same assert.true(actual, expected, message).
30. How can you use interface and how it is different from Abstract class?
Abstract class may have Abstract and concrete methods, and there is not any compulsion in adding abstract method in abstract class. But in Interface, we do have only abstract methods and we don’t need to write abstract keyword in Interface this is by default public and abstract.
Conclusion
Embarking on a journey into Java automation can be both exciting and rewarding. Armed with the foundational knowledge provided in this guide, you’re well-equipped to take on beginner-level Java automation interviews with confidence. Remember to practice and apply these concepts in real-world scenarios to solidify your understanding. Good luck on your automation journey!
In the realm of programming, simplicity often yields the most elegant solutions. When it comes to Java programming, a language known for its readability and versatility, finding duplicate characters in a string can be achieved with a straightforward approach. In this article, we’ll delve into a simple Java code snippet that helps you identify and understand duplicate characters within a given string. By the end of this article, you’ll have a solid grasp of the process and be well-equipped to tackle similar challenges in your coding journey.
Introduction to Duplicate Characters
Duplicate characters within a string refer to the occurrence of a specific character more than once. Detecting these duplicates is a fundamental task in programming, often required for data validation, manipulation, and analysis.
The Algorithm Overview
At its core, the algorithm we’ll discuss involves iterating through the characters of a given string and recording their occurrences. By using a data structure to store character counts, we can then identify characters with counts greater than one, indicating duplicates.
How to print duplicate character in given String by using scanner class ?
public class duplicate {
public static void main(String agrs[])
{
String str= "Helllo";
char[] carray = str.tocharArray();
System.out.println("Enter a String"+str);
System.out.println("duplicate character is in above string:");
for (int i = 0; i < str.length(); i++) {
for (int j = i + 1; j < str.length(); j++) {
if (carray[i] == carray[j]) {
System.out.print(carray[j] + " ");
break;
}
}
}
}
}
//Output : string is Hello
//duplicate character is in above string l
Real-world Applications
The ability to identify duplicate characters finds use in various scenarios. It aids in data cleansing, ensuring input validity, and enhancing the efficiency of certain algorithms that operate on strings.
Conclusion
In the realm of Java programming, simplicity often leads to powerful solutions. With the code snippet provided, you can now effortlessly identify duplicate characters within a given string. This fundamental skill will undoubtedly prove invaluable in your programming endeavors.
Are you a budding programmer or someone interested in learning more about Java? Well, you’re in luck! In this article, we’re going to dive deep into a Java program that counts the characters in a given string. Whether you’re a coding enthusiast or just curious about how programming works, this step-by-step guide will walk you through the process in a simple and engaging way.
Introduction to Character Counting
Character counting is a fundamental concept in programming and text processing. It involves determining the number of characters, including letters, digits, punctuation marks, and whitespace, in a given string. This process has various applications, such as analyzing text data, validating input, and enhancing user experience.
Understanding the Problem Statement
In our scenario, we have a user-input string, and our goal is to count the total number of characters in that string. This includes all characters, even spaces and punctuation marks.
Writing the Java Program: Step by Step
Importing the Necessary Libraries
import java.util.Scanner;
Taking User Input
Next, let’s write the code to take input from the user:
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a string: ");
String input = scanner.nextLine();
Initializing Variables
We’ll need a variable to keep track of the character count. Let’s initialize it to zero:
int count = 0;
Using a Loop to Count Characters
for (int i = 0; i < input.length(); i++) {
count++;
}
Displaying the Result
Finally, let’s display the total character count to the user:
System.out.println("Total characters in the string: " + count);
Testing Your Program
It’s time to put our program to the test! Compile and run the code, and enter a string when prompted. The program will calculate the character count and provide you with the result.
Tips for Optimizing Your Code
While our basic program works, there are ways to optimize it for efficiency. Consider using a more efficient algorithm to count characters, such as using the length() method directly, which eliminates the need for a loop.
Common Mistakes to Avoid
When working on similar programs, watch out for common mistakes like forgetting to import libraries, not initializing variables correctly, or using an incorrect loop condition.
Real-World Applications of Character Counting
Character counting finds its place in various real-world scenarios, such as:
Text editors and word processors for tracking document statistics.
Form validation to ensure input lengths meet specific criteria.
Language analysis and processing for linguistic research.
Conclusion
In this article, we embarked on a journey to explore character counting in Java. We discussed the importance of character counting, set up our Java environment, and dissected the step-by-step process of writing a program to count characters in a given string. Remember, programming is all about problem-solving and creativity. So, go ahead, experiment, and build upon what you’ve learned!
Are you a budding programmer diving into the world of Java? If so, you’ve come to the right place! In this article, we’ll explore how to write a Java program to find the reverse of a number. Whether you’re a seasoned coder looking for a quick refresher or a beginner taking the first steps in programming, this guide will walk you through the process step by step.
Introduction to Reversing a Number
Reversing a number involves rearranging its digits in the opposite order. For example, reversing the number 12345 would result in 54321. This seemingly simple task holds significant importance in programming and can be a building block for more complex algorithms.
Basic Concepts of Java Programming
Before we dive into the actual code, let’s briefly cover some fundamental concepts of Java programming that you’ll need to understand.
Java is an object-oriented programming language known for its platform independence, robustness, and versatility. It uses a syntax similar to C++, making it relatively easy to learn for those familiar with other programming language
Using Modulus Operator
One way to reverse a number is by using the modulus operator (%) to extract the digits one by one. Here’s a high-level overview of the process:
Initialize variables to store the original and reversed numbers.
Iterate through the digits of the original number using a loop.
Extract the last digit using the modulus operator and add it to the reversed number.
Remove the last digit from the original number using integer division.
Repeat steps 3 and 4 until all digits are processed.
Writing the Java Program
Reverse a Number Using While Loop –
public class reversenum {
public static void main(String agrs[])
{
int n = 12345, reverse=0;
while (n != 0)
{
int remainder = n%10;
reverse = reverse * 10+remainder;
n=n/10;
}
System.out.println("reverse number is :" +reverse);
}
}
//OUTPUT : reverse number is : 54321
Compiling and Running the Program
To compile and run the program, follow these steps:
Save the Java code in a file named reversenum.java.
Open a terminal or command prompt.
Navigate to the directory containing the reversenum.java file.
Compile the program by entering the command: javac reversenum.java
Run the compiled program with the command: java reversenum
Conclusion
Congratulations! You’ve successfully learned how to write a Java program to reverse a number using different techniques.
Are you gearing up for a job interview in the tech industry? If so, you might already know how crucial it is to be well-prepared for the barrage of questions that interviewers can throw your way. In the realm of software testing and automation, knowledge of Selenium is highly sought after. To help you shine during your interview, we’ve compiled a comprehensive list of Selenium interview questions and expertly crafted answers that will give you the confidence you need to succeed. Let’s dive in!
Common Interview Questions
1.Why Selenium is Important?
Selenium is an Open Source Tool and available for testing web based , Mobile app, APIs. We can test Cross Browser ,Different Platform .There are 4 Major component of selenium – Selenium Grid, Selenium IDE, Selenium RC, Selenium WebDriver. We can Save Cost, Efforts by Using Selenium Automation Tool.
6.What is the fundamental difference between XPath and CSS selectors?
The fundamental difference between XPath and CSS selector is – Using XPaths we can traverse up in the document i.e we can move to parent elements. Whereas using the CSS selector, we can only move downwards in the document.
7.Difference between Absolute and Relative XPath?
Absolute Path: Single Forward Slash, select the element from the root <html> and cover the whole path to the element. It is also known as complete or Full Xpath.
Relative Path: Double Forward Slash, Expression can starts in the middle of the HTML DOM structure.
[Slower]Example-//table/tbody/tr/th
8.Difference between getWindowHandle() and getWindowHandles() ?
getWindowHandle() returns the window handle id of the current browser window. getWindowHandles() returns the window handle id of all the browser windows.
9.How do you mouse hover on any element on a web page?
Using moveToElement() of Action class
10.What is the difference between ‘/’ and ‘//’ ?
“/” refers to the immediate child element in the html tree. “//” refers to any element in the html tree . It also represent any descendant .
11.What types of Test Case to be automated ?
Data driven test cases, higher complexity tests, smoke tests, TC with many databases updates.
12. What is used to run automation scripts on multiple system simultaneously?
Selenium Grid
13. Whar are different type of locators in Selenium ?
There are 8 types of Locators in Selenium : ID, ClassName, TagName, CssSelectors, Xpath, LinkText, Name, PartialLinkText,
14. How to capture screenshot in Selenium ?
public static void TakeSnapShot(WebDriver webdriver, String FilewithPath)
//Covert webdriver object to TakeScreenShot
TakeScreenShot scrshot = ((TakeScreenShot), webdriver);
//Call getScreenshotAs method to create an Image File
File ScrFile = scrShot.getScreenshotAs(OutputType.FILE);
15.How you will find hidden text in selenium?
Using getElementById methos we can identify element.
executor.executeScript("document.getElementById('txt').value ="selenium' ");
16. How do we clear Content of Text Box in Selenium ?
WebElement el = driver.findElement(By.Id("ElementID"));
el.clear();
17. How to execute java scripts function?
JavascriptExecutor js=(JavascriptExecutor) driver;
String title = (String) js.executeScript("pass your java script");
18. How to automate radio button in selenium ?
WebElement el = driver.findElement(By.id("Radio Button id"));
//to perform check operation
el.click();
//verify to radio button is check it return true if selected else false el.isSelected();
19. How to maximize window using selenium ?
driver.manage().window().maximize();
20. How you will handle alert popup in Selenium ?
//To click 'cancel' button in alert popup
driver.switch().alert().dismiss();
//To click on 'accept/ok' in alert popup
driver.switch().alert().accept();
//To send data or value on alert popup
driver.switch().alert().accept();
//To capture alert text in popup
driver.switch().alert().sendKeys("Text");
21. What is POM?
POM is Page Object Model its an object repository design pattern in selenium webdriver. POM creates our testing code maintainable and reusable. we can use POM with page factory or without page factory.
22. What are the Page Factory Annotations ?
@FindBy
@FindBys
@FindAll
@CacheLookUp
23. What is mean by POJO Class ?
POJO stands for Plain Old Java Object is used to describe the same thing as a “Normal Class” whereas a JavaBean follows a set of rules. Most commonly Beans use getters and setters to protect their member variables, which are typically set to private and have a no-argument constructor.
24. What is the difference between @FindBys and @FindAll ?
//@FindBys : When the required WebElement objects need to match all the given criteria use @FindBys annotation
@FindBys( {
@FindBy(className ="class1")
@FindBy(className ="class2") } )
Private List<WebElement>elementWithBoth_class1ANDclass2;
//@FindAll : When the required WebElement objects need to match atleast one of the given criteria use @FindAll annotation
@FindAll ( {
@FindBy(className ="class1")
@FindBy(className ="class2") } )
Private List<WebElement>elementWithEither_class1ANDclass2;
25. What is difference between Implicit wait and Explicit wait ?
Implicit wait : sets a timeout for all successive web element searches. for the specified amount of time it will try looking for element again and again before throwing a NoSuchElementException. It waits for elements to show up .
Explicit Wait : It is a one-timer, used for a particular search.
WebDriverWait wait = new WebDriverWait(WebDriverRefrence , TimeOut);
26. What is Syntax of XPath ?
XPath = //tagname[@attribute= 'Value']
// ---> select current node.
Tagname --->Tagname of particular node.
@---> Select attribute
Attribute--->attribute name of the node
Value--->Value of the attribute
27. What is difference between in Assert & Verify ?
Verify : Verify command will check whether the element is on the page, if it is not then test will carry on executing, In verification, All command are going to run guaranteed even if any of test fails.
Assert : Assert allows to check whether an element is on page or not. The Test will stop on the step failed, If the asserted element is not available, In other words, Test will terminated at the point where check fails.
28. What is difference between find elements & find element ?
findElement() : It finds the first element within current page using the given ” Locating Mechanism “. It returns a single WebElement.
findElements() : Using the given ” Locating Mechanism ” it will find all Elements within Current page. It returns a List of WebElements.
31. If we have findElement and there is no element & findElements there is no elements so what will return ?
findElement – it will throw an exception findEelements– it will return 0 value
32. What is difference between Explicit wait & Fluent Wait ?
Explicit Wait : It is a one-timer, used for a particular search, it used to tell the web driver to wait for certain conditions( Expected Conditions) or maximum time exceeded before throwing an error “ElementNotVisibleException” Exception.
WebDriverWait wait = new WebDriverWait(WebDriverReference , TimeOut);
Fluent Wait : it used to define maximum time for the web driver to wait for conditions as well as the frequency with which we want to check the condition before throwing an”ElementNotVisibleException” Exception. it checks for the web element at regular intervals untill the object is found or timeout happens.
wait wait = new FluentWait(WebDriver Reference).withTimeout(timeout, SECONDS).pollingEvery(timeout, SECONDS).ignoring(Exception.class);
Conclusion
Mastering Selenium interview questions can be the key to unlocking exciting career opportunities in the tech industry. By understanding the core concepts, techniques, and best practices discussed in this article, you’ll be well-equipped to impress interviewers with your knowledge and expertise in Selenium automation testing. Remember, preparation is the cornerstone of success, so keep practicing and refining your skills. Good luck on your interview journey!
Are you looking to enhance your Java programming skills? One fundamental concept every Java developer should understand is string manipulation. In this article, we will delve into the intriguing world of reversing strings in Java. We’ll explore different techniques, provide code examples, and offer practical insights that will empower you to write efficient and elegant string reversal programs. Let’s embark on this exciting journey of mastering the Java reverse string program!
Introduction to String Reversal
What is String Reversal?
String reversal is a common programming task that involves rearranging the characters of a string in reverse order. In Java, this process can be accomplished using various techniques, each with its own advantages and considerations.
Why is String Reversal Important in Java?
String manipulation is a fundamental aspect of programming, and mastering string reversal can lead to more efficient and elegant code. Whether you’re working on text processing, data analysis, or user interface development, understanding how to reverse strings will undoubtedly prove invaluable.
Using a For Loop
public class reversestring{
public static void main(String args[]){
String str="Hello";
String rev=" ";
char[] carray = str.toCharArray();
System.out.println("String is"+str);
for(int i=0;i<str.length;i--){
rev=str.charAt(i)+rev;
}
System.out.ptintln("Reverse String is"+rev);
}
}
//OUTPUT : Reverse String is : olleH
Using StringBuilder Method
Leveraging the StringBuilder Class
The StringBuilderclass in Java provides a convenient and efficient way to manipulate strings. It offers a method calledreverse() that allows us to reverse the characters within a StringBuilder object.
// Java code example for string reversal using StringBuilder
public class StringReversal {
public static String reverseString(String input) {
StringBuilder stringBuilder = new StringBuilder(input);
return stringBuilder.reverse().toString();
}
}
Using the reverse() Method
The reverse() method of the StringBuilder class internally modifies the character array, resulting in a reversed string. This approach is particularly efficient for large strings.
Using Recursive Solution
Understanding Recursion
Recursion is a powerful programming concept where a function calls itself to solve a smaller subproblem. We can implement a recursive approach to reverse a string by swapping characters from the beginning and end recursively.
// Java code example for recursive string reversal
public class StringReversal {
public static String reverseString(String input) {
if (input.length() <= 1) {
return input;
}
return reverseString(input.substring(1)) + input.charAt(0);
}
}
Implementing Recursive String Reversal
In the recursive approach, the base case is when the length of the string is 1 or less, in which case the string itself is returned. Otherwise, the first character is appended to the reversed substring of the remaining characters.
Performance Comparison
Analyzing Time and Space Complexity
As we explore different methods of string reversal, it’s important to consider their performance characteristics. The traditional loop-based methods have a time complexity of O(n), where n is the length of the string. The space complexity is O(n) as well due to the character array or StringBuilderused.
On the other hand, the recursive approach also has a time complexity of O(n), but it requires additional memory for the function call stack, leading to a space complexity of O(n).
Best Practices
Considerations for Choosing an Approach
When choosing a string reversal approach, consider factors such as the size of the input string, memory constraints, and performance requirements. Each method has its own trade-offs, and the best choice will depend on the context of your application.
Error Handling and Input Validation
While implementing a string reversal program, it’s important to incorporate error handling and input validation. Ensure that the input string is not null or empty before performing any operations, and handle potential exceptions gracefully.
Conclusion
In this comprehensive guide, we explored the fascinating world of reversing strings in Java. We covered traditional methods using loops and character manipulation, advanced techniques using the StringBuilder class, and even delved into the realm of recursion. By mastering string reversal, you’ve added a valuable tool to your programming arsenal.
Remember to consider factors such as performance, memory usage, and application requirements when choosing a string reversal approach. Whether you’re a beginner or an experienced developer, the knowledge you’ve gained here will undoubtedly serve you well in your programming journey.
Are you gearing up for a manual testing job interview? As you prepare to showcase your skills and expertise, it’s crucial to have a solid grasp of the most commonly asked manual testing interview questions and their insightful answers. In this comprehensive guide, we’ll dive deep into the world of manual testing, equipping you with the knowledge and confidence to ace your interview.
Common Interview Question
1. What is Manual Testing?
To verify Software or Requirement Manually it called as Manual Testing Where QA Team find bugs & Issues, defect without using any Tool. It insures whether Software or App meets as per the business requirements or not. There are Multiple types of testing –
Black Box Testing
Grey Box Testing
White Box Testing
Advantage of Manual Testing : More Reliable Limited Cost Easy to Learn for New People Useful Product with short Life Cycle
2. What is Smoke Testing ?
To verify stability of an Application Where we check build is stable or not . Once Development is done so Development team will release a build and Testing Team will check the Build Whether they are able to download or Open URL or not that under comes in Smoke Testing
3. What is Sanity Testing?
Sanity Testing is also Part of Regression we can say, It verify to relationality of an Application or Software. We check Major functionalities of an Application we do not test deeply that is called Sanity Testing.
4. What is Regression Testing?
Its type of software Testing that is done to verify that code changes in the software doesn’t impact to existing functionalities or bug any fixes in the existing features.
Types of Regression Testing:
UI Regression
Retest All
Regression Test Selection
Complete Regression
Prioritization Regression
5. What is Functional Testing?
Functional Testing is to check the functionality and verify each function/feature of the software or an Application whereas non-functional testing Verifies usability, reliability, performance.
6. What is Difference between Smoke & Sanity Testing?
Smoke Testing is to verify stability of an application where Sanity Testing is to verify relationality of an application.
Smoke Testing is subset of acceptance Testing where Sanity Testing is subset of Regression Testing.
Smoke Testing is done by Testers or Developers both where Sanity Testing done by only Testers.
Smoke Testing is to verify critical functionalities where Sanity Testing is to verify new functionality like bug.
Smoke Testing verify entire system from end to end where Sanity Testing verify only particular Component.
7. What is Difference Between Error , Defect /Bug & Failure?
Error : Any incorrect human action that produces a problem in the system is called an error. Failure : The deviation identified by end user while using the system is called a failure. Defect/Bug : Deviation from the expected behavior to the actual behavior of the system is called defect.
8. What is Verification & Validation ?
Verification :checks whether we are building the right system •Verification typically involves. •Reviews •Walkthroughs •Inspections Validation :Checks whether we are building the system right. •Takes place after verifications are completed. •Validation typically involves actual testing. •System Testing
9. What is Difference between Static V/S Dynamic Testing ?
Static testing :It is an approach to test project documents in the form of Reviews, Walkthroughs and Inspections. Dynamic testing :It is an approach to test the actual software by giving inputs and observing results.
11. What is difference between System Testing & Integration Testing ?
System Testing : Testing over all functionality of the application with respective client requirements. •It is a black box testing technique. •This testing is conducted by testing team. •Before conducting system testing we should know the requirements. •System Testing focusses on below aspects. •User Interface Testing (GUI) •Functional Testing •NonFunctional Testing •Usability Testing
Integration Testing : In Integration Testing, individual software modules are integrated logically and tested as a group. •Integration testing focuses on checking data communication amongst these modules. •Integrated Testing is white box testing technique. •Integrated testing is conducted by the developers. •Approaches: •Top Down Approach •Bottom Up Approach •Sandwich Approach(Hybrid)
12. What is difference between Black-Box , White-box & Grey-Box Testing ?
Black Box Testing : Testing conducts on functionality of the application whether it is working according to customer requirements or not. Ex: System Testing & UAT Testing
White Box Testing : White Box Testing conducts on internal logic of the programs, Programming Skills are required. Ex: Unit Testing & Integration Testing
Grey Box Testing : Both combination of white box and black box testing. Ex: Database Testing
13.What is Graphical User Interface ?
There are two types of interfaces in a computer application. •Command Line Interface is where you type text and computer responds to that command. •Graphical User Interface where you interact with the computer using images rather than text.
14. What is Functional Testing ? Its an Object Properties Coverage •Input Domain Coverage (BVA, ECP) •Database Testing/Backend Coverage •Error Handling Coverage •Calculations/Manipulations Coverage •Links Existence & Links Execution •Cookies & Sessions & Object Properties Testing
15. What is Database Testing ?
During Database testing Test Engineers validate the data w.r.t database, Validates DML operations(Insert , Update, Delete & Select )SQL Language: DDL, DML, DCL etc..
16. What is DML Commands ?
DML Data Manipulation language Insert, update, select, delete .
17. What is difference between DCL & DDL Commands?
DCL Commit, roll back etc. DDL Data Definition Langue Create , alter, drop
18. What is Error Handling Testing?
Validate error messages thrown by the application when we provide invalid data , The error messages should be clear and easy to understand to the user.
19. What is difference between Cookies & Sessions ?
Cookie: Temporary internet files which are created at client side when we open the web sites. These files contains User data. Session :Sessions are time slots which are allocated to the user at the serve side.
21. What is difference between Load & Stress Testing ?
Load:Testing speed of the system while increasing the load gradually till the customer expected number. Stress:Testing speed of the system while increasing/reducing the load on the system to check any where its breaking.
22. What is Volume Testing ?
Volume: Check how much volumes of data is able to handle by the system.
23. What is Security Testing? •Testing security provided by the system. •Types: •Authentication •Access Control/Authorization •Encryption/Decryption
24. What is Compatibility Testing? •Testing Compatibility of the system w.r.t OS, H/W & Browsers. •Operating System Compatibility •Hardware Compatibility (Configuration Testing) •Browser Compatibility •Forward & Backward Compatibility
25. What is Difference between Adhoc Testing & Monkey Testing ?
Adhoc : Software testing performed without proper planning and documentation.
Monkey : Testing is carried out with the knowledge of the tester about the application and the tester tests randomly without following the specifications/requirements.
26. What is difference between Re-Testing & Regression Testing ?
Re-Testing: Testing functionality repetitively is called re-testing.
Re-testing gets introduced in the following two scenarios.
Testing is functionality with multiple inputs to confirm the business validation are implemented (or) not.
Testing functionality in the modified build is to confirm the bug fixers are made correctly (or)not.
Regression Testing: It is a process of identifying various features in the modified build where there is a chance of getting side effects and retesting these features.
The new functionalities added to the existing system (or) modifications made to the existing system.
It must be noted that a bug fixer might introduce side effects and a regression testing is helpful to identify these side effects
27.Explain Defect Life Cycle ?
28. What is Characteristics of good Test Case? •A good test case has certain characteristics which are: •Should be accurate and tests what it is intended to test. •No unnecessary steps should be included in it. •It should be reusable. •It should be traceable to requirements. •It should be compliant to regulations. •It should be independent i.e. You should be able to execute it in any order without any dependency on other test cases. •It should be simple and clear, any tester should be able to understand it by reading once.
29. What are QA/Testing Activities? •Understanding the requirements and functional specifications of the application. •Identifying required Test Scenario’s. •Designing Test Cases to validate application. •Execute Test Cases to valid application •Log Test results ( How many test cases pass/fail ). •Defect reporting and tracking. •Retest fixed defects of previous build •Perform various type of testing assigned by Test Lead (Functionality, Usability, User Interface and compatibility) etc., •Reports to Test Lead about the status of assigned tasks •Participated in regular team meetings. •Creating automation scripts for Regression Testing. •Provides recommendation on whether or not the application / system is ready for production.
30. What is RTM ?
% of Test cases Executed: No.of Test cases executed / Total No. of Test cases written ) * 100
% of test cases NOT executed: (No.of Test cases NOT executed/Total No. of Test cases written) * 100
% Test cases passed: (No.of Test cases Passed /Total Test cases executed) * 100
% Test cases failed: (No.of Test cases failed / Total Test cases executed) * 100
%Test cases blocked: (No.of test cases blocked / Total Test cases executed ) * 100
Defect Density: Number of defects identified per requirement/s: No.of defects found / Size(No. of requirements)
Defect Removal Efficiency (DRE): (A / A+B ) * 100 A-(Fixed Defects / (Fixed Defects + Missed defects) ) * 100. A-Defects identified during testing/ Fixed Defects B-Defects identified by the customer/Missed defects
Defect Leakage: (No.of defects found in UAT / No. of defects found in Testing) * 100
Defect Rejection Ratio: (No. of defect rejected /Total No. of defects raised) * 100
Defect Age: Fixed date Reported date
Customer satisfaction= No.of complaints per Period of time
Conclusion
In conclusion, mastering manual testing interview questions and answers is essential for showcasing your expertise and landing your dream job. By understanding the fundamental concepts, strategies, and scenarios covered in this guide, you’ll be well-equipped to excel in your manual testing interviews and contribute to the quality assurance of software applications. Good luck on your journey to becoming a successful manual tester!
In today’s digital age, APIs (Application Programming Interfaces) play a pivotal role in connecting and interacting with various web services. One of the most versatile and widely used methods to make API calls is by utilizing the powerful CURL library in PHP, which is also commonly employed in the context of WordPress. This article will provide you with a step-by-step guide on how to perform API calls using CURL in PHP and WordPress, enabling you to harness the full potential of external data and services seamlessly.
Introduction to API Calls and CURL
APIs serve as intermediaries that allow different software systems to communicate with each other. CURL, short for Client URL, is a command-line tool and library that enables data transfer through various protocols. In PHP, CURL provides a convenient way to make HTTP requests to APIs, making it an essential tool for developers.
Types of Methods
POST : To create a New Request
GET : To Retrieve a Request
DELETE : To Remove a Request
PATCH : To Update Partial an Existing Request
PUT : To Update a Request
As of now PHP has introduce new concept to call any API in our web application. Using those function we can easily call API.
What is CURL ? Curl stands for Client URL is PHP library that allows the user to create an HTTP request and allows to send and retrieve data from an URL to our Application. Create a file name called test-curl.php inside your project directory and paste code into it.
WordPress, a popular content management system, can also benefit from CURL-powered API calls. By creating custom functions, you can seamlessly integrate external data into your WordPress site.
function fetch_api_data() {
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, 'https://api.example.com/data');
$response = curl_exec($curl);
curl_close($curl);
// Process the response and return data
return json_decode($response, true);
}
Best Practices for Optimized API Calls
To ensure efficient and optimized API calls, consider implementing caching mechanisms, adhering to rate limits, and monitoring API usage.
Conclusion
In this comprehensive guide, we’ve explored the world of API calls using CURL in PHP and WordPress. You’ve learned how to set up your environment, make basic and advanced API requests, handle errors, and integrate API calls within WordPress. By mastering these techniques, you can unlock a world of possibilities for data integration and enrichment in your web applications.
