EasyMock - Adicionando comportamento

EasyMock adiciona uma funcionalidade a um objeto fictício usando os métodos expect() e expectLassCall(). Dê uma olhada no seguinte trecho de código.

//add the behavior of calc service to add two numbers
EasyMock.expect(calcService.add(10.0,20.0)).andReturn(30.00);

Aqui instruímos o EasyMock a fornecer um comportamento de adição de 10 e 20 ao método add de calcService e, como resultado, retornar o valor de 30,00.

Neste ponto, Mock simplesmente registrou o comportamento, mas não está funcionando como um objeto simulado. Depois de chamar o replay, ele funciona conforme o esperado.

//add the behavior of calc service to add two numbers
EasyMock.expect(calcService.add(10.0,20.0)).andReturn(30.00);

//activate the mock
//EasyMock.replay(calcService);

Exemplo sem EasyMock.Replay ()

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

Arquivo: 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

Arquivo: 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

Vamos testar a classe MathApplication, injetando nela uma simulação de calculatorService. O Mock será criado pela EasyMock.

Arquivo: MathApplicationTester.java

import org.easymock.EasyMock;
import org.easymock.EasyMockRunner;
import org.easymock.Mock;
import org.easymock.TestSubject;

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;

//@RunWith attaches a runner with the test class to initialize the test data
@RunWith(EasyMockRunner.class)
public class MathApplicationTester {
	
   // @TestSubject annotation is used to identify the class which is going to use the mock object
   @TestSubject
   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
      EasyMock.expect(calcService.add(10.0,20.0)).andReturn(30.00);

      //activate the mock
      //EasyMock.replay(calcService);	
		
      //test the add functionality
      Assert.assertEquals(mathApplication.add(10.0, 20.0),30.0,0);
   }
}

Step 4: Execute test cases

Crie um arquivo de classe java chamado TestRunner em C:\>EasyMock_WORKSPACE para executar o (s) caso (s) de teste.

Arquivo: 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

Compile as classes usando javac compilador da seguinte forma:

C:\EasyMock_WORKSPACE>javac Calculator Service.java Math Application.java Math Application Tester.java Test Runner.java

Agora execute o Test Runner para ver o resultado:

C:\EasyMock_WORKSPACE>java TestRunner

Verifique a saída.

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

Exemplo com EasyMock.Replay ()

Step 1: Create an interface called CalculatorService to provide mathematical functions.