Creating unit tests

For unit testing, we are using JUnit, which is a popular Java-based unit testing library. The following source code shows an example skeleton of the Spring Boot test class. The @SpringBootTest annotation specifies that the class is a regular test class that runs Spring Boot-based tests. The @Test annotation before the method specifies to JUnit that the method can be run as a test case:

@SpringBootTest
public  class  MyTestsClass  {
  @Test
  public  void  testMethod()  {
    // Test case code
  }
}

First, we will create our first test case that will test the major functionality of our application before we create any formal test cases. Proceed as follows:

1. Open the CardatabaseApplicationTest test class that has already been made for your application. There is one test method called contextLoads here, and this is where we will add the test. The...