Spock Framework

Step 1: Create a Spock specification for the `Calculator` class.

Step 2: Define a test method for each arithmetic operation (addition, subtraction, multiplication, division).

Step 3: Use the `given`, `when`, `then` blocks to set up the calculator instance, perform the operation, and assert the result.

Step 4: Run the specification to verify the calculator's functionality.

Step 1: Create a Spock specification for the service.

Step 2: Use Spock's mocking capabilities to create mocks for the external dependencies.

Step 3: Configure the mocks to return specific values or throw exceptions.

Step 4: Inject the mocks into the service and run the tests.

Step 1: Use a REST client library (e.g., Rest-assured) to make requests to the API endpoints.

Step 2: Create a Spock specification to define the expected behavior of the endpoints.

Step 3: Use the `given`, `when`, `then` blocks to set up the API request, execute the request, and assert the response.

Step 4: Validate the response status code, headers, and body.

Step 1: Create a Spock specification to test the data validation logic.

Step 2: Use Spock's data-driven testing feature to define multiple input values and expected validation results.

Step 3: Use the `where` block to specify the input data and expected results.

Step 4: Assert that the validation logic produces the expected results for each input set.

Step 1: Create a Spock specification to test the exception handling logic.

Step 2: Use the `when` block to execute the code that should throw an exception.

Step 3: Use the `then` block to assert that the expected exception is thrown.

Step 4: Validate the exception message and other properties.