public class AdderTest { @Test public void testAddition() { Adder adder = new Adder(); int result = adder.add(2, 3); assertEquals(5, result); // verifies if the expected result is equal to the actual result } }Here, we are using the assertEquals() method to compare the expected result with the actual result obtained from the add() method. The org.junit.Assert package is part of JUnit, which is an open-source testing framework for Java. The package is located in the "junit-4.13.1.jar" file, and the package structure is "org.junit.Assert".