Interview Questions.

Q1. What Are The Advantages Of Using Jwebunit?

JWebUnit provides a excessive-degree Java API for navigating an internet software blended with a fixed of assertions to verify the utility's correctness. This consists of navigation through hyperlinks, shape access and submission, validation of table contents, and different typical business internet software features.

The easy navigation techniques and prepared-to-use assertions permit for more speedy take a look at creation than using only JUnit or HtmlUnit. And if you want to interchange from HtmlUnit to other plugins inclusive of Selenium (to be had quickly), there's no need to rewrite your tests.

Q2. What Is Jwebunit?

WebUnit is a Java-primarily based checking out framework for internet applications. It wraps existing testing frameworks together with HtmlUnit and Selenium with a unified, easy trying out interface to can help you quickly check the correctness of your net packages.

Q3. What Are Junit Classes? List Some Of Them?

JUnit instructions are essential instructions which are used in writing and testing JUnits. Some of the essential lessons are −

Assert − It carries a hard and fast of assert techniques.

TestCase − It incorporates a check case defines the fixture to run more than one exams.

TestResult − It carries methods to acquire the effects of executing a test case.

TestSuite − It is a Composite of Tests.

Q4. What Is A Test Runner?

Test runner is used for executing the check instances.

Q5. What Is The Purpose Of

This will perform the approach after all assessments have completed. This can be used to perform easy-up activities.

Q6. What Is A Test Suite?

Test suite me bundle a few unit check cases and run it collectively. In JUnit, both @RunWith and @Suite annotation are used to run the suite check.

Q7. How To Create Parameterized Tests?

There are 5 steps, which you need to observe to create Parameterized exams−

Annotate check magnificence with @RunWith(Parameterized.Elegance).

Create a public static approach annotated with @Parameters that returns a Collection of Objects (as Array) as test statistics set.

Create a public constructor that takes in what's equal to at least one "row" of take a look at information.

Create an instance variable for every "column" of take a look at statistics.

Create your tests case(s) the usage of the example variables as the supply of the check information.

The test case could be invoked as soon as per every row of records. Let's see Parameterized assessments in motion.

Q8. What Is Unit Testing?

Unit checking out is the testing of unmarried entity (magnificence or approach). Unit trying out could be very critical to each software organization to give a first-class product to their customers.

Q9. What Are Annotations And How Are They Useful In Junit?

Annotations are like meta-tags that you could add to you code and observe them to strategies or in class. The annotation in JUnit gives us statistics approximately check techniques, which strategies are going to run earlier than & after test strategies, which techniques run earlier than & after all the strategies, which techniques or class may be forget about for the duration of execution.

Q10. What Is The Purpose Of

Several assessments need comparable items created before they are able to run. Annotating a public void technique with @Before causes that technique to be run before each Test approach.

Q11. What Is The Purpose Of Org.Junit.Junitcore Class?

The test cases are completed the usage of JUnitCore class. JUnitCore is a facade for jogging assessments. It supports running JUnit 4 checks, JUnit 3.Eight.X assessments, and mixtures.

Q12. What Is Manual Testing?

Executing the take a look at cases manually without any tool aid is referred to as manual checking out.

Q13. What Is Automated Testing?

Taking device help and executing the take a look at instances with the aid of the usage of automation tool is known as automation trying out.

Q14. Can You Use A Main() Method For Unit Testing?

Yes you could test the use of most important() approach. One obvious gain appears to be that you can whitebox take a look at the class. That is, you could take a look at the internals of it (non-public strategies as an instance). You cannot do this with unit-assessments. But commonly the check framework assessments the interface and the conduct from the person's angle.

Q15. How Do You Test A "blanketed" Method?

When a method is declared as "blanketed", it may only be accessed in the identical package deal in which the class is described. Hence to check a "protected" technique of a goal elegance, define your test elegance inside the identical bundle because the target magnificence.

Q16. What Is A Unit Test Case?

A Unit Test Case is a part of code which ensures that the some other part of code (technique) works as expected. To gain the ones desired consequences quick, take a look at framework is needed .JUnit is perfect unit check framework for java programming language.

Q17. What Happens If A Junit Test Method Is Declared To Return "string"?

If a JUnit check method is declared to return "String", the compilation will skip good enough. But the execution will fail. This is due to the fact JUnit calls for that each one test methods have to be declared to go back "void".

Q18. What Is The Purpose Of Org.Junit.Testsuite Class?

A TestSuite is a Composite of Tests. It runs a collection of test cases.

Q19. Why Does Junit Only Report The First Failure In A Single Test?

Reporting more than one disasters in a single test is generally a signal that the check does an excessive amount of and it's far too huge a unit take a look at. JUnit is designed to paintings fine with a number of small exams. It executes every test inside a separate example of the check elegance. It reviews failure on each test.

Q20. What Is Cactus?

Cactus is a easy check framework for unit checking out server-facet java code (Servlets, EJBs, Tag Libs, Filters). The rationale of Cactus is to decrease the cost of writing exams for server-facet code. It makes use of JUnit and extends it. Cactus implements an in-box approach, that means that tests are done within the field.

Q21. Name Some Of The Junit Extensions?

Following are the JUnit extensions −

Cactus

JWebUnit

XMLUnit

MockObject

Q22. What Is Junit?

JUnit is a Regression Testing Framework used by developers to enforce unit checking out in Java and boost up programming velocity and increase the satisfactory of code.

Q23. When Are Unit Tests Written In Development Cycle?

Tests are written before the code at some stage in development so that it will assist coders write the nice code.

Q24. What Are The Core Components Of Cactus?

Cactus Ecosystem is fabricated from numerous components −

Cactus Framework is the heart of Cactus. It is the engine that gives the API to write down Cactus checks.

Cactus Integration Modules are front ends and frameworks that provide easy approaches of the usage of the Cactus Framework (Ant scripts, Eclipse plugin, Maven plugin).

Q25. How Do You Test A "private" Method?

When a technique is asserted as "personal", it can only be accessed in the same elegance. So there's no way to check a "non-public" method of a target class from any check elegance. Hence you want to carry out unit trying out manually. Or you need to trade your approach from "private" to "included".

Q26. How Do You Use Test Fixtures?

Fixtures is a fixed nation of a hard and fast of items used as a baseline for strolling tests. The reason of a check fixture is to make sure that there is a widely known and glued environment wherein checks are run so that consequences are repeatable. It includes −

setUp() technique which runs before every check invocation.

TearDown() method which runs after every test approach.

Q27. How To Simulate Timeout Situation In Junit?

Junit gives a handy alternative of Timeout. If a take a look at case takes greater time than specific number of milliseconds then Junit will mechanically mark it as failed. The timeout parameter is used together with @Test annotation.

Q28. What Are The Advantages Of Automated Testing?

Following are the benefits of automated trying out −

Fast − Automation runs check instances appreciably quicker than human resources.

Less funding in human sources − Test instances are executed with the aid of using automation device so much less tester are required in automation testing.

More reliable − Automation assessments carry out precisely same operation whenever they may be run.

Programmable − Testers can program sophisticated exams to carry out hidden records.

Q29. How Will You Run Junit From Command Window?

Follow the stairs under −

Set the CLASSPATH

Invoke the runner −java org.Junit.Runner.JUnitCore 

Q30. What Is Xmlunit?

XMLUnit provides a single JUnit extension magnificence, XMLTestCase, and a hard and fast of assisting training.

Q31. What Is The Purpose Of

If you allocate outside sources in a Before technique you want to release them after the check runs. Annotating a public void technique with @After reasons that approach to be run after the Test technique.

Q32. What Is The Purpose Of Org.Junit.Assert Class?

This elegance affords a hard and fast of assertion strategies beneficial for writing assessments. Only failed assertions are recorded.

Q33. What Is The Purpose Of Org.Junit.Testresult Class?

A TestResult collects the consequences of executing a check case. It is an example of the Collecting Parameter sample. The check framework distinguishes between screw ups and errors. A failure is anticipated and checked for with assertions. Errors are unanticipated problems like an ArrayIndexOutOfBoundsException.

Q34. In Java, Assert Is A Keyword. Won't This Conflict With Junit's Assert() Method?

JUnit 3.7 deprecated assert() and changed it with assertTrue(), which works exactly the identical manner. JUnit four is like minded with the assert key-word. If you run with the -ea JVM switch, assertions that fail might be pronounced through JUnit.

Q35. Do You Need To Write A Test Class For Every Class That Needs To Be Tested?

No. We need not write an independent test class for each class that needs to be examined. If there may be a small group of tests sharing a not unusual test fixture, you can circulate the ones checks to a brand new check class.

Q36. How Do I Test Things That Must Be Run In A J2ee Container (e.G. Servlets, Ejbs)?

Refactoring J2EE components to delegate capability to different items that don't need to be run in a J2EE box will enhance the layout and testability of the software program. Cactus is an open supply JUnit extension that can be used for unit testing server-aspect java code.

Q37. Why Not Just Use System.Out.Println() For Testing?

Debugging the code the usage of device.Out.Println() will lead to manual scanning of the complete output each time the program is administered to make sure the code is doing the anticipated operations. Moreover, in the long run, it takes lesser time to code JUnit techniques and take a look at them on elegance documents.

Q38. What Is The Purpose Of

Annotating a public static void approach with @BeforeClass causes it to be run once earlier than any of the take a look at techniques within the magnificence.

Q39. What Are Important Features Of Junit?

Following are the critical functions of JUnit −

It is an open supply framework.

Provides Annotation to become aware of the test techniques.

Provides Assertions for checking out expected results.

Provides Test runners for going for walks tests.

JUnit assessments may be run robotically and that they test their personal results and offer instantaneous remarks.

JUnit checks can be organized into test suites containing test cases and even different check suites.

JUnit indicates test progress in a bar that is green if take a look at is going quality and it turns crimson when a test fails.

Q40. What Are Parameterized Tests?

Junit 4 has delivered a new function Parameterized tests. Parameterized exams permit developer to run the same test again and again once more the use of special values.

Q41. How To Compile A Junit Test Class?

Compiling a JUnit check class is like compiling some other Java instructions. The handiest thing you want watch out is that the JUnit JAR file must be blanketed in the classpath.

Q42. Explain The Execution Procedure Of The Juint Test Api Methods?

Following is how the JUnit execution system works −

First of all approach annotated as @BeforeClass execute best once.

Lastly, the technique annotated as @AfterClass executes best once.

Method annotated as @Before executes for each test case but earlier than executing the take a look at case.

Method annotated as @After executes for every check case however after the execution of test case.

In among approach annotated as @Before and technique annotated as @After each test case executes.

Q43. What Is Testing?

Testing is the procedure of checking the functionality of the software whether it's far running as consistent with necessities.

Q44. Explain Unit Testing Using Mock Objects?

The not unusual coding fashion for trying out with mock objects is to −

Create instances of mock gadgets.

Set state and expectancies inside the mock items.

Invoke domain code with mock gadgets as parameters.

Verify consistency in the mock gadgets.

Q45. Name The Tools With Which Junit Can Be Easily Integrated?

JUnit Framework may be easily included with both of the followings −

Eclipse

Ant

Maven

Q46. What Are The Core Features Of Junit?

JUnit take a look at framework provides following important capabilities −

Fixtures

Test suites

Test runners

JUnit instructions

Q47. What Are The Disadvantages Of Manual Testing?

Following are the hazards of manual trying out −

Time ingesting and tedious − Since check cases are done with the aid of human assets so it is very gradual and tedious.

Huge funding in human sources − As test instances want to be completed manually so extra testers are required in manual trying out.

Less dependable − Manual testing is much less dependable as checks may not be performed with precision on every occasion due to human mistakes.

Non-programmable − No programming can be executed to put in writing state-of-the-art tests which fetch hidden information.

Q48. What Happens If A Junit Test Method Is Declared As "private"?

If a JUnit check approach is asserted as "private", it compiles successfully. But the execution will fail. This is due to the fact JUnit requires that all test techniques must be declared as "public".

Q49. What Is A Mock Object?

In a unit take a look at, mock objects can simulate the behavior of complicated, actual (non-mock) gadgets and are consequently beneficial whilst a real item is impractical or not possible to contain into a unit test.

Q50. What Is The Purpose Of

The Test annotation tells JUnit that the general public void method to which it is attached can be run as a take a look at case.