Mockito - Richiami

Mockito fornisce un'interfaccia di risposta che consente lo stubbing con un'interfaccia generica.

Sintassi

//add the behavior to add numbers
when(calcService.add(20.0,10.0)).thenAnswer(new Answer<Double>() {
   @Override
   public Double answer(InvocationOnMock invocation) throws Throwable {
      //get the arguments passed to mock
      Object[] args = invocation.getArguments();
      //get the mock 
      Object mock = invocation.getMock();	
      //return the result
      return 30.0;
   }
});

Esempio

Step 1 − Create an interface called CalculatorService to provide mathematical functions

File: CalculatorService.java

public interface CalculatorService {
   public double add(double input1, double input2);
   public double subtract(double input1, double input2);
   public double multiply(double input1, double input2);
   public double divide(double input1, double input2);
}

Step 2 − Create a JAVA class to represent MathApplication

File: MathApplication.java

public class MathApplication {
   private CalculatorService calcService;

   public void setCalculatorService(CalculatorService calcService){
      this.calcService = calcService;
   }
   
   public double add(double input1, double input2){
      return calcService.add(input1, input2);		
   }
   
   public double subtract(double input1, double input2){
      return calcService.subtract(input1, input2);
   }
   
   public double multiply(double input1, double input2){
      return calcService.multiply(input1, input2);
   }
   
   public double divide(double input1, double input2){
      return calcService.divide(input1, input2);
   }
}

Step 3 − Test the MathApplication class

Testiamo la classe MathApplication, inserendovi una simulazione di calculatorService. Mock sarà creato da Mockito.

Qui abbiamo aggiunto una chiamata al metodo mock, add () all'oggetto mock tramite when (). Tuttavia, durante i test, abbiamo chiamato subtract () prima di chiamare add (). Quando creiamo un oggetto fittizio utilizzando Mockito.createStrictMock (), l'ordine di esecuzione del metodo è importante.

File: MathApplicationTester.java

import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
import static org.mockito.Mockito.inOrder;

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InOrder;
import org.mockito.runners.MockitoJUnitRunner;

// @RunWith attaches a runner with the test class to initialize the test data
@RunWith(MockitoJUnitRunner.class)
public class MathApplicationTester {
	
   private MathApplication mathApplication;
   private CalculatorService calcService;

   @Before
   public void setUp(){
      mathApplication = new MathApplication();
      calcService = mock(CalculatorService.class);
      mathApplication.setCalculatorService(calcService);
   }

   @Test
   public void testAdd(){

      //add the behavior to add numbers
      when(calcService.add(20.0,10.0)).thenAnswer(new Answer<Double>() {

         @Override
         public Double answer(InvocationOnMock invocation) throws Throwable {
            //get the arguments passed to mock
            Object[] args = invocation.getArguments();
			
            //get the mock 
            Object mock = invocation.getMock();	
			
            //return the result
            return 30.0;
         }
      });

      //test the add functionality
      Assert.assertEquals(mathApplication.add(20.0, 10.0),30.0,0);
   }
}

Step 4 − Execute test cases

Crea un file di classe java denominato TestRunner in C:\> Mockito_WORKSPACE per eseguire uno o più casi di test.

File: TestRunner.java

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner {
   public static void main(String[] args) {
      Result result = JUnitCore.runClasses(MathApplicationTester.class);
      
      for (Failure failure : result.getFailures()) {
         System.out.println(failure.toString());
      }
      
      System.out.println(result.wasSuccessful());
   }
}

Step 5 − Verify the Result

Compila le classi usando javac compilatore come segue -

C:\Mockito_WORKSPACE>javac CalculatorService.java MathApplication.
   java MathApplicationTester.java TestRunner.java

Ora esegui il Test Runner per vedere il risultato:

C:\Mockito_WORKSPACE>java TestRunner

Verifica l'output.

true