Ottieni java.lang.NullPointerException quando provi a prendere in giro il metodo privato con mockito e powermock

Question

Sto provando a prendere in giro un metodo privato con mockito/powermock. Ottengo NullPointerException
Il semplice esempio che sto cercando di fare è:

classe reale

import com.siriusforce.plugin.common.PluginSystem; 
import com.wellsfargo.core.business.service.dp.fulfillment.MockitoBusinessService; 

public class MockitoBusinessOperationImpl implements MockitoBusinessOperation{ 
    private MockitoBusinessService mockitoBusinessService = PluginSystem.INSTANCE.getPluginInjector().getInstance(MockitoBusinessService.class); 
    private Long Id; 

    public String creditAproved(Long Id){ 
     System.out.println("Came Inside MockitoBusinessOperationImpl"); 
     this.Id = Id; 
     if (this.Id != null){ 
      System.out.println("Inside creditaproved If statement"); 
      String Report = mockitoBusinessService.creditReport(this.Id); 
      System.out.println("Mock Object Injected from test class "+ Report); 
      return Report; 
     } else 
      return "Went to Else Part"; 
    } 

    private String inTestMethod(Long Id){ 
     return "this is working"; 
    } 
} 

Classe di prova:

import static org.mockito.Mockito.spy; 
import static org.mockito.Mockito.when; 
import static org.powermock.api.mockito.PowerMockito.doReturn; 

import org.mockito.InjectMocks; 
import org.mockito.Mock; 
import org.mockito.MockitoAnnotations; 
import org.powermock.core.classloader.annotations.PrepareForTest; 
import org.testng.annotations.BeforeMethod; 
import org.testng.annotations.Test; 

import com.siriusforce.plugin.common.PluginSystem; 

public class MockitoBusinessServiceTest { 

    @Mock 
    MockitoBusinessService MockitoBusinessService ; 

    @InjectMocks  
    private MockitoBusinessOperation MockitoBusinessOperation = PluginSystem.INSTANCE.getPluginInjector().getInstance(MockitoBusinessOperation.class); 

    private Long Id; 

    @BeforeMethod 
    public void init() { 
     MockitoAnnotations.initMocks(this); 
     this.Id = 123L; 
    } 

    @PrepareForTest(MockitoBusinessOperation.class) 
    @Test(enabled = true) 
    public void testReCalculatePrepaids() throws Exception { 
     MockitoBusinessOperation = spy(MockitoBusinessOperation); 
     doReturn("this will work hopefully").when(MockitoBusinessOperation, "inTestMethod", this.Id); 

     when(MockitoBusinessService.creditReport(this.Id)).thenReturn(new String("Decline by only Me")); 

     String mainReport = MockitoBusinessOperation.creditAproved(this.Id); 
     System.out.println("Indirect Call from actual class MainReport " + mainReport); 

    } 
} 

Quando provo a fare funzionare questo ho a NullPointerException: qualsiasi suggerimento che risolva questo o qualsiasi altro modo di deridere un metodo privato. Non voglio usare il suggerimento dato per rendere il metodo protetto che significa cambiare il metodo attuale. Non voglio alcuna modifica l'attuale

class method 
    <failure type="java.lang.NullPointerException">java.lang.NullPointerException 

at org.powermock.api.mockito.internal.expectation.PowerMockitoStubberImpl.addAnswersForStubbing(PowerMockitoStubberImpl.java:68) 

at org.powermock.api.mockito.internal.expectation.PowerMockitoStubberImpl.prepareForStubbing(PowerMockitoStubberImpl.java:123) 

at org.powermock.api.mockito.internal.expectation.PowerMockitoStubberImpl.when(PowerMockitoStubberImpl.java:91) 

at com.wellsfargo.core.business.service.dp.fulfillment.MockitoBusinessServiceTest.testReCalculatePrepaids(MockitoBusinessServiceTest.java:54) 

Answer 1

È necessario utilizzare PowerMockito.spy() invece di Mockito.spy()!

tenta di importare static org.powermock.api.mockito.PowerMockito.spy;