JUnit - Paramethy testing

JUnit - Paramethy testing

Junit 4 introduces a new feature for paramethy testing. P aramethy tests allow developers to run the same test repeatedly with different values. Y ou'll follow 5 steps to create a paramethy test.

• Comment @RunWith test class .class (parameterized) .
• Create a public @Parameters commented by the object, which returns a collection (array) of objects as a collection of test data.
• Create a common constructor that accepts something equal to a row of test data.
• Create an instance variable for each column of test data.
• Use instance variables as a source of test data to create your test cases.

Once each row of data appears the test case will be called. L et's look at the paramethy tests in the activity.

Create a class

• In C: T his JUNIT_WORKSPACE to test by creating a java class .java PrimeNumberChecker.

public class PrimeNumberChecker {
   public Boolean validate(final Integer primeNumber) {
      for (int i = 2; i < (primeNumber / 2); i++) {
         if (primeNumber % i == 0) {
            return false;
         }
      }
      return true;
   }
}

Create a Parameterized Test Case class

• Create a java class called PrimeNumberCheckerTest .java the data.

Create a java class JUNIT_WORKSPACE primeNumberCheckerTest in the C:;.java file name.

import java.util.Arrays;
import java.util.Collection;

import org.junit.Test;
import org.junit.Before;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;
import org.junit.runner.RunWith;
import static org.junit.Assert.assertEquals;

@RunWith(Parameterized.class)
public class PrimeNumberCheckerTest {
   private Integer inputNumber;
   private Boolean expectedResult;
   private PrimeNumberChecker primeNumberChecker;

   @Before
   public void initialize() {
      primeNumberChecker = new PrimeNumberChecker();
   }

   // Each parameter should be placed as an argument here
   // Every time runner triggers, it will pass the arguments
   // from parameters we defined in primeNumbers() method
   public PrimeNumberCheckerTest(Integer inputNumber, 
      Boolean expectedResult) {
      this.inputNumber = inputNumber;
      this.expectedResult = expectedResult;
   }

   @Parameterized.Parameters
   public static Collection primeNumbers() {
      return Arrays.asList(new Object[][] {
         { 2, true },
         { 6, false },
         { 19, true },
         { 22, false },
         { 23, true }
      });
   }

   // This test will run 4 times since we have 5 parameters defined
   @Test
   public void testPrimeNumberChecker() {
      System.out.println("Parameterized Number is : " + inputNumber);
      assertEquals(expectedResult, 
      primeNumberChecker.validate(inputNumber));
   }
}

Create a TestRunner class

Create a java class JUNIT_WORKSPACE file name TestRunner in the C:.java to execute the test case

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner {
   public static void main(String[] args) {
      Result result = JUnitCore.runClasses(PrimeNumberCheckerTest.class);
      for (Failure failure : result.getFailures()) {
         System.out.println(failure.toString());
      }
      System.out.println(result.wasSuccessful());
   }
}

The PrimeNumberChecker, PrimeNumberCheckerTest, and TestRunner classes are compiled with javac.

C:\JUNIT_WORKSPACE>javac PrimeNumberChecker.java PrimeNumberCheckerTest.java
TestRunner.java

Now run TestRunner, which will run the test cases defined by the provided Test Case class.

C:\JUNIT_WORKSPACE>java TestRunner

Verify the output.

Parameterized Number is : 2
Parameterized Number is : 6
Parameterized Number is : 19
Parameterized Number is : 22
Parameterized Number is : 23
true