Difference Between TestNG and JUnit Software Development Life Cycle (SDLC) has various phases for the development of software requirement analysis, Communication, Designing, Coding, Testing, and Deployment and software testing plays a vital role in the software development to deploy efficiently. Software Testing makes sure that the product that is to be delivered fulfills the requirements of the client or for what purpose it was being designed. Software testing is achieved in two ways either manually or automatically. JUnit and TestNG are the Java frameworks for unit testing that are considered to be the most popular and widely used, java platform supports a variety of testing frameworks that can be used for unit testing. Unit Testing Unit testing is to isolate each part of the program and show that the individual parts are correct and provide a strict, written contract that the piece of code must satisfy. The unit testing alerts the development team of the problem before handing the code off to testers or clients, potential problems are caught early in the development process. Maintaining and writing unit tests can be made faster by using parameterized tests and these are supported by TestNG, JUnit, and its .Net counterpart, XUnit. Unit Testing Tools: ● TestNG ● JUnit ● NUnit ● Mockito ● PHPUnit Advantages Of Unit Testing ● It makes the process of debugging easier. ● Unit Testing forces better code and design whether you are using C#, Java, Python, JavaScript, or Php and it means you have well-defined code with high cohesion. ● Unit Testing is essentially doing quality assurance of the code. ● Unit Testing allows the refactoring of code and makes integration simpler it finds changes and helps maintain and adjust code, reducing bugs and defects, and verifying the accuracy of each unit. ● Unit Testing helps find problems and resolve them before further testing so they won’t impact other bits of code and includes bugs in a programmer's execution and issues with a specification for the unit itself. Disadvantages of Unit Testing ● Test code should be fairly simple and this testing method is still more work and more code which means more hours and more cost. ● By definition, unit testing focuses on a single piece of software, As a result, it is incapable of detecting integration or system-wide issues. ● May not be possible to test a unit for every input scenario that will occur in a real-world environment. ● Evaluating all execution paths is not possible in unit testing, So testing cannot catch every error in a program. ● Must maintain rigorous documentation. JUnit JUnit is an open-source framework used for writing and executing unit tests in Java programming language. JUnit is one of the best-known unit testing frameworks. This tool helps to enhance the efficiency of the developer, which provides the consistency of the development code and reduces the time of debugging. JUnit provides a basic built-in template so that you may write small, simple test cases in no time and tests help you to write independent modules, thereby bettering the coverage of tests and the quality of the application. It does not support running parallel tests simultaneously.JUnit offers the assertions for testing expected results. Advantages Of JUnit ● JUnit is an AWT based and swing graphical test reporting mechanism, and also provides a text-based command line. ● It's widely adopted by organizations around the world for performing unit testing in Java programming language. ● JUnit is a standard for testing in Java programming language and it is supported by almost all the IDEs. ● It's one of the best testing frameworks that can be selected for an efficient testing process. Disadvantages Of JUnit ● JUnit Cannot do dependency testing as opposed to the TestNG framework. ● JUnit is not suitable for higher-level testing i.e. for large test suites. ● JUnit can’t create HTML reports of test cases. Use ANT to create HTML test reports in JUnit. ● JUnit cannot do group testing, Which is available in TestNG. TestNG It's a Java framework that facilitates software tests in Java and it runs the tests in classes. TestNG makes classes for corresponding tests and then processes them. TestNG was developed by Cedric Beust. TestNG is capable of supporting more advanced annotation. When it's compared to JUnit, TestNG makes it simpler to write tests and configure them. TestNG uses the same Classes to run all of its tests and manages threads to run procedures, which makes the overall functioning of the checking tests faster and it's also thought of as a flexible tool for performing tests. TestNG framework can be easily integrated with Maven. Jenkins, etc. Annotations used in a TestNG framework are easily understandable. Preconditions annotations, Test annotations, and Postcondition annotations are used in the TestNG. Advantages Of TestNG over JUnit ● Grouping: In TestNG, Perform a lot of complex automation testing because of its ability to group test cases and execute the groups. We can not perform group tests in JUnit. ● Extent Classes: In TestNG, Don’t need to extend any classes. We have to use extended classes in JUnit. ● Mandatory Annotations: In TestNG, No constraints for any type of mandatory annotations. We have to use mandatory annotations like @BeforeClass and @AfterClass in JUnit. ● Wider Range of annotations: Wider range of annotations support like @Before/After Suite , @Before/After Test , @Before/After Groups ● Dependency Test: In TestNG, Can use the “depends on methods” to perform the dependency test.Doesn't support this feature in JUnit. ● Parallel Test Execution: Perform parallel test execution if run through XML.Doesn’t support this feature in JUnit. ● Test Order: TestNG is better than JUnit when test execution is done in a specific order and methods with lower priority values will be executed first. ● Listeners: TestNG supports various types of listeners and can be used by adding annotations.No mechanism in JUnit to add listeners using annotations. Disadvantages Of TestNG ● TestNG setup is time-consuming. ● If the project does not require test case prioritization then the TestNG case is of no use. ● less commonly used compared to JUnit, fewer people were having experience with it. Conclusion TestNG and JUnit are annotation based and TestNG is better in terms of ease of use. Both of them provide easy integration with major IDEs and are similar.JUnit is better than TestNG for injecting test methods input data. TestNG and JUnit supports the execution of test cases from the java main method and Both of them are similar in terms of Assertions support. If you want to skip tests based on conditions and execute tests in a specific order then JUnit is better.TestNG listener support is much better than JUnit.We provide TestNG and JUnit services with a team of QA experts at Sanesquare Technologies, If you have any questions or comments, you can contact us.