Detailed explanation of the technical principles of Testng in the Java library
Testng is a powerful Java test framework that is widely used in unit testing, integration testing and end -end testing.This article will introduce the technical principles of Testng in the Java class library and provide relevant Java code examples.
1. Testng overview
Testng is an open source test framework. Its design is inspired by Junit and Nunit, but it is more powerful and flexible than the two.Testng provides rich testing functions, such as test kit, dependency test, parameterized testing, test results reports, etc., and also supports multi -threaded testing and distributed testing.
Second, the core principle of testng
1. Comment drive
TESTNG uses annotations to identify test methods, tests, etc., and analyze and execute testing according to the annotation.Common annotations include @Test, @Befacetest, @Aftertest, @DataProvider, etc.Through these annotations, we can easily control the execution order and related configuration of test cases.
For example, in the code below, a @Test annotation is used to identify a test method:
@Test
public void testAddition() {
int result = Calculator.add(3, 5);
Assert.assertEquals(result, 8);
}
2. Test kit
Testng allows a set of related test methods or test classes to be combined into a test kit for execution in order.This is very useful for the management and organization of test cases.
import org.testng.annotations.Test;
import org.testng.TestListenerAdapter;
import org.testng.TestNG;
public class TestSuiteExample {
public static void main(String[] args) {
TestListenerAdapter tla = new TestListenerAdapter();
TestNG testng = new TestNG();
testng.setTestClasses(new Class[] {TestClass1.class, TestClass2.class});
testng.addListener(tla);
testng.run();
}
}
3. Dependent test
Testng supports the execution order of the test case -based dependencies based on methods.By using the "DependSonMethods" property, we can specify the dependency of the test method.In this way, when a method of dependence fails, the method of dependencies will not be executed.
@Test
public void testLogin() {
// Test code for login
}
@Test(dependsOnMethods = {"testLogin"})
public void testSearch() {
// Test code for search
}
4. Parameterization test
Testng allows parameterized testing by data -driven.By using @DataProvider annotations, we can specify a set of parameter for testing methods to run the same test method multiple times, but use different input data.This can greatly simplify the writing of test cases.
@DataProvider(name = "testData")
public Object[][] dataProvider() {
return new Object[][] {
{"apple", "red"},
{"banana", "yellow"}
};
}
@Test(dataProvider = "testData")
public void testFruit(String fruit, String color) {
// Test code for fruit
}
5. Test results report
Testng generates a detailed test results report, which can identify which tests, which failures, which are skipped, etc.By default, Testng will generate a HTML format report, which provides visual test results and statistics.
3. Summary
Testng, as a powerful test framework, provides rich test functions and flexible configuration options.The characteristics of the annotation driver, test kit, dependency test, parameterization testing, and test results report make the test in the Java class library more convenient and efficient.
The above is a detailed introduction to the technical principles of Testng in the Java class library. I hope to help you understand the working principle of Testng.
