Java Fundamentals. Home Assignment. Reflection

The task is to implement a simplistic test execution engine.

Test execution should follow the rules manifested by the annotations provided with the framework:

1. @Test - indicates that a class is a test class and for a method it indicates that this is a test method to be executed. Alternatively, the test class can implement the TestCase marker interface with no annotations. Examples:

public class FibTest implements TestCase { 

@Test
public class FibTest { 

2. @Expected - if the test failes with exception, the framework should be able to handle the failure and mark the test as passed.

@Expected(RuntimeException.class)
public void compareIntegers() { 
    assertEquals(4, 5);
}

In the example above, the equality assertion for the numbers 4 and 5 will throw RuntimeException. The test engine should handle the exception: if the method is marked with @Expected annotation and the annotation parameter matches the exception type that was thrown by test method execution, then the test should be considered as successful.

NB! In case if the test method doesn't throw an exception but it is annotated with @Expected, then the test should be considered as FAILED, since we are expecting that the test to fail and it doesn't - so it doesn't meet our exepectations.

NB! If the test throws an exception which is subclass of the declared exception type, then it is a valid situation and the test should be marked as a successful one.

3. @Inject - injects a proxy into a field for the specified class instance, e.g:

@Inject(Fib.class)
Fibonacci fib;

The proxy should count the invocations of the target methods. Print the total number of invocations in the execution summary.

Tests are executed by TestExecutor class and you will have to implement the missing methods:

1. getClasses(String packageName) : find all test classes in a given package. Hint: you can obtain an instance of a relevant class loader:

ClassLoader classLoader = Thread.currentThread().getContextClassLoader();

And then apply ClassLoader.getResources(...) method to locate the available class files. Remember that you can load classes dynamically by fully qualified name: Class.forName("org.zeroturnaround.jf.hw.tests.MyTest")

2. executeTests(Class<?> clazz) : execute the tests for a given class (instance).

Expected behavior:

Package org.zeroturnaround.jf.hw.tests provides some examples of the tests that we would like to run with the test engine.

Here's the expected output from FibTest execution:

SUCCESS: FibTest.find1stFibonacciNumber
SUCCESS: FibTest.find2ndAnd3rdFibonacciNumber
SUCCESS: FibTest.find10thFibonacciNumber
FAILURE: FibTest.find15thFibonacciNumberWithFailure: EXPECTED: 55, ACTUAL: 610
SUMMARY: EXECUTED 4, PASSED 3, FAILED 1, BUSINESS METHODS INVOKED 5

Notes:

EXECUTED 4 - FibTest has 4 methods marked with @Test annotation and 4 of them were executed

PASSED 3 - 3 tests passed successfully

FAILED 1 - 1 test failed (find15thFibonacciNumberWithFailure)

BUSINESS METHODS INVOKED 5 - fib.calculate() was invoked 5 times