Mockito - Menambahkan Perilaku

Mockito menambahkan fungsionalitas ke objek tiruan menggunakan metode when(). Lihatlah cuplikan kode berikut.

//add the behavior of calc service to add two numbers
when(calcService.add(10.0,20.0)).thenReturn(30.00);

Di sini kami telah menginstruksikan Mockito untuk memberikan perilaku menambahkan 10 dan 20 ke add metode dari calcService dan sebagai hasilnya, mengembalikan nilai 30,00.

Pada titik waktu ini, Mock merekam perilaku tersebut dan merupakan objek tiruan yang berfungsi.

//add the behavior of calc service to add two numbers
when(calcService.add(10.0,20.0)).thenReturn(30.00);

Contoh

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

Mari kita uji kelas MathApplication, dengan memasukkan tiruan kalkulatorService di dalamnya. Mock akan dibuat oleh Mockito.

File: MathApplicationTester.java

import static org.mockito.Mockito.when;

import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.runners.MockitoJUnitRunner;

// @RunWith attaches a runner with the test class to initialize the test data
@RunWith(MockitoJUnitRunner.class)
public class MathApplicationTester {
	
   //@InjectMocks annotation is used to create and inject the mock object
   @InjectMocks 
   MathApplication mathApplication = new MathApplication();

   //@Mock annotation is used to create the mock object to be injected
   @Mock
   CalculatorService calcService;

   @Test
   public void testAdd(){
      //add the behavior of calc service to add two numbers
      when(calcService.add(10.0,20.0)).thenReturn(30.00);
		
      //test the add functionality
      Assert.assertEquals(mathApplication.add(10.0, 20.0),30.0,0);
   }
}

Step 4 − Execute test cases

Buat file kelas java bernama TestRunner di C:\>Mockito_WORKSPACE untuk menjalankan kasus uji.

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

Kompilasi kelas menggunakan javac kompiler sebagai berikut -

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

Sekarang jalankan Test Runner untuk melihat hasilnya -

C:\Mockito_WORKSPACE>java TestRunner

Verifikasi hasilnya.

true