Learning the technical principles of the Junit Vintage Engine framework

Learn about the technical principles of the JUNIT VINTAGE ENGINE framework Junit Vintage Engine is a sub -module in Junit 5. Its purpose is to support the Junit 3 and Junit 4 test kits running old versions on the Junit 5 platform.The engine adopts a compatible layer, allowing the old version of the test kit to run smoothly on the Junit 5 platform, and at the same time compatible with Junit 4's runtime model. Before understanding the technical principles of Junit Vintage Engine, we must first understand the evolution process of Junit's version.Junit is one of the earliest Java test frameworks. Its first version was Junit 1, which later developed to Junit 2 and Junit 3 versions.Junit 4 introduces some important new features, such as the improvement of the test driven test and an assertion mechanism.Subsequently, Junit 5 was fully rewritten based on the new features of the Java 8, and introduced the modularization, annotation driver and more scalability of the previous versions of the previous versions. However, due to the complexity of the JVM ecosystem and the special needs of some traditional projects, many developers are still using the old version of Junit for testing.In order to protect their investment and move to Junit 5, the Junit team has developed the Junit Vintage Engine engine.Below we will learn more about its technical principles. Junit Vintage Engine's working principle can be summarized as the following steps: 1. Introduction dependencies: First of all, you need to add Junit Vintage Engine as a dependent item to the construction file of the project.Through Maven or Gradle, you can simply introduce Junit Vintage Engine's dependence items and ensure that the Junit 5 platform is also added to the project. 2. Create a Junit 3 or Junit 4 test kit: Next, create a test kit based on the test kit grammar of Junit 3 or Junit 4.Junit Vintage Engine uses Junit 5's annotation driving method to indicate the test test using the Vintage engine through the `@runwith (junitvintage.class)` `annotation.In this way, the old version of the test kit can run on the Judit 5 platform. For example, the following is an example of a Junit 3 test kit: @RunWith(JUnitVintage.class) public class JUnit3TestSuite { public static TestSuite suite() { TestSuite suite = new TestSuite(); suite.addTestSuite(MyTestClass1.class); suite.addTestSuite(MyTestClass2.class); return suite; } } 3. Run the test kit: When running a test kit of Junit 3 or Junit 4, Junit Vintage Engine will dynamically create the corresponding Junit 5 testing operator and provide adapter to compatible with the old version of the test kit.The adapter will analyze the structure of the Junit 3 or JDIT 4 test kit, and maximize the test cases and the adapter, so as to perform these old version of the test on the Junit 5 platform. 4. Collect test results: Junit Vintage Engine will collect the test results during the execution and convert it to the test results of Junit 5.In this way, the test results of Junit 3 or Junit 4 can be easily integrated with the test report of Junit 5. In summary, Junit Vintage Engine provides a compatible layer, so that the old version of the Junit 3 and Junit 4 test kits can run seamlessly on the Junit 5 platform.Its technical principles mainly include the introduction of a test kit that is introduced and using adapters to run the old version, and handles and conversion test results.In this way, the development team can gradually migrate and unify the Junit test framework, while enjoying the new features and expansion capabilities provided by Junit 5. I hope this article will help you understand the technical principles of the Junit Vintage Engine framework.If necessary, the following is a sample code that uses the simplest use of jinit vintage engine:: import junit.framework.TestCase; import org.junit.Test; import org.junit.runner.RunWith; import org.junit.vintage.engine.annotation.VintageEngine; @RunWith(VintageEngine.class) public class JUnit3Test extends TestCase { public void testAddition() { int result = 2 + 2; assertEquals(4, result); } @Test public void testSubtraction() { int result = 5 - 3; assertEquals(2, result); } } This example defines a test class that inherits the TestCase class inherited from the Junit 3.`@Runwith (vintagengine.class)` `Note Specifying the test using the Vintage engine to run the test.The test method TestAdDition tested the addition, and the test method TestSubtraction using the Junit 4 annotation tested the subtraction.Through the Junit Vintage Engine engine, both test methods can be run in Junit 5. Wish you success when you use the Junit Vintage Engine framework!