Mockito - Ripristino di Mock

Mockito offre la possibilità di ripristinare un mock in modo che possa essere riutilizzato in seguito. Dai un'occhiata al seguente frammento di codice.

//reset mock
reset(calcService);

Qui abbiamo ripristinato l'oggetto fittizio. MathApplication fa uso di calcService e dopo aver reimpostato il mock, l'utilizzo del metodo mocked fallirà il test.

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.

File: MathApplicationTester.java

package com.tutorialspoint.mock;

import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;
import static org.mockito.Mockito.reset;

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
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 testAddAndSubtract(){

      //add the behavior to add numbers
      when(calcService.add(20.0,10.0)).thenReturn(30.0);
  
      //test the add functionality
      Assert.assertEquals(mathApplication.add(20.0, 10.0),30.0,0);

      //reset the mock	  
      reset(calcService);

      //test the add functionality after resetting the mock
      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.

testAddAndSubtract(MathApplicationTester): expected:<0.0> but was:<30.0>
false