Applying TDD to reverse a number
You've seen Test-Driven Development — now let's apply it! Consider a simple method to reverse an int. If you think in terms of TDD, the first thing you need to do is write a test. Focus on the behavior (input and output) of the method, not on its implementation. This will train you to put the project requirements first.
In the code snippet below, complete the test with the expected output, the expression to obtain the method's actual output, and the expression inside the assertEquals() statement.
Este ejercicio forma parte del curso
Introduction to Testing in Java
Instrucciones del ejercicio
- Enter the correct reversed value for the input number.
- Invoke the
IntReversermethodreverse()to acquire the actual value. - JUnit expects the
expected/actualvalues in a specific order. Enter them intoassertEquals().
Ejercicio interactivo práctico
Prueba este ejercicio y completa el código de muestra.
public class IntReverser {
public static int reverse(int input) {
return 0;
}
public static class IntReverserTest {
@Test
public void testReverse_reversesNumber() {
int input = 1234;
// Write down the expected return value
int expected = ____;
// Call the reverse() method to obtain its actual return value
int actual = IntReverser.____(____);
// Write the arguments for the assert statement in the correct order
assertEquals(____, ____);
}
}
public static void main(String[] args) {
launchTestsAndPrint(IntReverserTest.class);
}
}