Styjun

I'm writing the Junit test case for a class which is extended by an abstract class. This base abstract class has an autowired object of a different class which is being used in the class I'm testing.
I'm trying to mock in the subclass, but the mocked object is throwing a NullPointerException.

Example:

// class I am testing
public class GetTransactionsForProcessorGroupActivity extends GetTransactionsBaseActivity 

 private static final Logger log = LogManager.getLogger(GetTransactionsForProcessorGroupActivity.class);

 public GetTransactionsForProcessorGroupActivity(ARHFactory arhFactory, MetricsFactory metricsFactory) 
 super(arhFactory, metricsFactory);
 


 @Override
 protected List<OverseasTransaction> getOverseasTransactions(Document herdDocument)
 throws IllegalDateFormatException, ProcessorConfigurationException, DocumentException 
 final String paymentProcessorGroup = HerdDocumentUtils.getPaymentProcessor(herdDocument);
 final Date runDate = HerdDocumentUtils.getRunDate(herdDocument);

 final List<String> paymentProcessorList = ProcessorGroupLookup.getProcessorsFromGroup(paymentProcessorGroup);
 List<OverseasTransaction> overseasTransactionList = new ArrayList<OverseasTransaction>();
 List<ProcessorTransactionWindow> processingWindows = new ArrayList<ProcessorTransactionWindow>();

 for (final String processor : paymentProcessorList) 
 ProcessorTransactionWindow transactionWindow = ProcessorCalendarUtils.getProcessorTransactionWindow(processor, runDate);
 processingWindows.add(transactionWindow);

 final Date processingFromDate = transactionWindow.getFromDate();
 final Date processingToDate = transactionWindow.getToDate();
//NullpointerException on this line, as OverseasTransactionStore mock object returns null.
 final List<OverseasTransaction> transactions = overseasTransactionsStore
 .queryOverseasTransactionsOnPPTimelineandDates(processor, processingFromDate, processingToDate);
 overseasTransactionList.addAll(transactions);
 

 HerdDocumentUtils.putProcessingWindowDetails(herdDocument, processingWindows);
 return overseasTransactionList;
 



// Base class
public abstract class GetTransactionsBaseActivity extends CoralHerdActivity implements ActionRequestHandler 

 private static final Logger log = LogManager.getLogger(GetTransactionsBaseActivity.class);

 @SuppressWarnings("unchecked")
 private static final Map<String, String> S3_CONFIGURATION = AppConfig.findMap(Constants.S3_CONFIGURATION_KEY);
 private static final String S3_BUCKET = S3_CONFIGURATION.get(Constants.BUCKET_NAME);

 private static final class Status 
 private static final String PROCESSOR_DETAILS_NOT_FOUND = "NoPaymentProcessorDetailsPresent";
 private static final String TRANSACTIONS_OBTAINED = "TransactionsObtained";
 private static final String NO_TRANSACTIONS_TO_BE_CONSIDERED = "NoTransactionsToBeConsidered";
 private static final String NEGATIVE_OR_ZERO_AMOUNT = "NegativeOrZeroAmount";
 

 protected final ARHFactory arhFactory;

 protected final MetricsFactory metricsFactory;

 @Autowired
 OverseasTransactionsStore overseasTransactionsStore;

 @Autowired
 S3ClientProvider s3ClientProvider;


 protected abstract List<OverseasTransaction> getOverseasTransactions(Document herdDocument)
 throws IllegalDateFormatException, ProcessorConfigurationException, DocumentException;

 @Override
 public ActionResponse postActionRequest(final ActionRequest request) throws Exception 
 TimedARH timedARH = (TimedARH) arhFactory.createARH();
 timedARH.setHandler(this);
 return timedARH.handle(request);
 

 public ActionResponse handle(final ActionRequest request) throws Exception 
 final Document herdDocument = HerdDocumentUtils.getFundFlowDocument(request);
 final Metrics metrics = MetricsLogger.getMetrics(metricsFactory);

 final String paymentProcessor = HerdDocumentUtils.getPaymentProcessor(herdDocument);

 try 
 final List<OverseasTransaction> overseasTransactionList;
 MetricsLogger.logFundFlowExecution(metrics, paymentProcessor);

 try 
 overseasTransactionList = getOverseasTransactions(herdDocument);
 catch (ProcessorConfigurationException e) 
 return new ActionComplete(Status.PROCESSOR_DETAILS_NOT_FOUND, herdDocument);
 

 if (CollectionUtils.isEmpty(overseasTransactionList)) 
 MetricsLogger.logTransactionMetrics(metrics, paymentProcessor, 0, BigDecimal.ZERO);
 return new ActionComplete(Status.NO_TRANSACTIONS_TO_BE_CONSIDERED, herdDocument);
 

 final String s3ObjectKey = getS3ObjectKey(request, paymentProcessor);
 storeTransactionsInS3(overseasTransactionList, S3_BUCKET, s3ObjectKey);

 final int itemCount = overseasTransactionList.size();
 BigDecimal totalAmount = BigDecimal.ZERO;
 for (OverseasTransaction overseasTransaction : overseasTransactionList) 
 if (StringUtils.equalsIgnoreCase(overseasTransaction.getType(), Constants.TRANSACTION_TYPE_CHARGE)) 
 totalAmount = totalAmount.add(overseasTransaction.getOverseasAmount());
 else if (StringUtils.equalsIgnoreCase(overseasTransaction.getType(), Constants.TRANSACTION_TYPE_REFUND)) 
 totalAmount = totalAmount.subtract(overseasTransaction.getOverseasAmount());
 
 

 MetricsLogger.logTransactionMetrics(metrics, paymentProcessor, itemCount, totalAmount);

 HerdDocumentUtils.putS3Location(herdDocument, S3_BUCKET, s3ObjectKey);
 HerdDocumentUtils.putTotalAmount(herdDocument, totalAmount);
 HerdDocumentUtils.putTransactionItemCount(herdDocument, itemCount);
 HerdDocumentUtils.putPaymentProcessor(herdDocument, paymentProcessor);

 if (totalAmount.compareTo(BigDecimal.ZERO) <= 0) 
 log.info("Total amount to disburse is zero or negative. ", totalAmount);
 return new ActionComplete(Status.NEGATIVE_OR_ZERO_AMOUNT, herdDocument);
 

 return new ActionComplete(Status.TRANSACTIONS_OBTAINED, herdDocument);
 finally 
 MetricsLogger.closeMetrics(metrics);
 
 




// Test class
@RunWith(PowerMockRunner.class)
@PowerMockIgnore( "javax.management.*" )
@PrepareForTest( HerdDocumentUtils.class, ProcessorGroupLookup.class )
public class GetTransactionsForProcessorGroupActivityTest extends AppConfigInitializedTestBase 

 private static HerdInput herdInput;
 private static HerdOutput herdOutput;
 private static final String paymentProcessorGroup = "BillDesk";
 private static final String paymentProcessorGroupNotFound = "IndiaPaymentGateway";

 @Mock
 ActionRequest request;

 @Mock
 WorkItemIdentifier workItemId;

 @Mock
 private CoralHerdActivity coralHerdActivity;

 @Mock
 Metrics metrics;

 @Mock
 Map<String, String> S3_CONFIGURATION_MAP;

 @Mock
 MetricsFactory metricsFactory;

 @Mock
 ARHFactory arhFactory;

 @Mock
 Document herdDocument;

 @Mock
 OverseasTransactionsStore overseasTransactionsStore;

 @Mock
 S3ClientProvider s3ClientProvider;

// @InjectMocks
// GetTransactionsForProcessorGroupActivity getTransactionsBaseActivityTest;

 // new GetTransactionsForProcessorGroupActivity(arhFactory, metricsFactory);

 @Before
 public void setup() 

 MockitoAnnotations.initMocks(this);
 PowerMockito.mockStatic(HerdDocumentUtils.class);
 // PowerMockito.mockStatic(ProcessorGroupLookup.class);
 // GetTransactionsBaseActivity getTransactionsBaseActivity = new GetTransactionsBaseActivity(overseasTransactionsStore);

 

 @Test
 public void testEnact() 
 GetTransactionsForProcessorGroupActivity getTransactionsForProcessorGroupActivity = Mockito
 .mock(GetTransactionsForProcessorGroupActivity.class, Mockito.CALLS_REAL_METHODS);
 Mockito.when(coralHerdActivity.enact(herdInput)).thenReturn(herdOutput);
 final HerdOutput actualHerdOutput = getTransactionsForProcessorGroupActivity.enact(herdInput);
 Assert.assertNotNull(actualHerdOutput);
 

 @Test
 public void testgetpaymentProcessorList() throws Exception 
 Date date = new Date();
 List<String> paymentProcessorList;
 PowerMockito.when(HerdDocumentUtils.getPaymentProcessor(herdDocument)).thenReturn(paymentProcessorGroup);
 PowerMockito.when(HerdDocumentUtils.getRunDate(herdDocument)).thenReturn(date);
 paymentProcessorList = ProcessorGroupLookup.getProcessorsFromGroup(paymentProcessorGroup);
 assertNotNull(paymentProcessorList);
 

 @Test(expected = ProcessorConfigurationException.class)
 public void testpaymentProcessorListNotFound() 
 Date date = new Date();
 PowerMockito.when(HerdDocumentUtils.getPaymentProcessor(herdDocument))
 .thenReturn(paymentProcessorGroupNotFound);
 PowerMockito.when(HerdDocumentUtils.getRunDate(herdDocument)).thenReturn(date);
 List<String> paymentProcessorList = ProcessorGroupLookup.getProcessorsFromGroup(paymentProcessorGroupNotFound);
 assertNotNull(paymentProcessorList);
 

 @Test
 public void canGetOverseasTransactiontest() throws Exception 

 GetTransactionsForProcessorGroupActivity getTransactionsForProcessorGroupActivity = Mockito
 .mock(GetTransactionsForProcessorGroupActivity.class);
 // OverseasTransactionsStore overseasTransactionsStore =
 // Mockito.mock(OverseasTransactionsStoreImpl.class);

 Date date = new Date();
 MockitoAnnotations.initMocks(this);
 PowerMockito.when(HerdDocumentUtils.getPaymentProcessor(herdDocument)).thenReturn(paymentProcessorGroup);
 PowerMockito.when(HerdDocumentUtils.getRunDate(herdDocument)).thenReturn(date);
// List<String> paymentProcessorList = new ArrayList<>();
// paymentProcessorList.add("BillDesk");
// PowerMockito.when(ProcessorGroupLookup.getProcessorsFromGroup(paymentProcessorGroup))
// .thenReturn(paymentProcessorList);
 String fromDate = "Sat Mar 16 23:59:59 IST 2019";
 String toDate = "Sat Mar 16 23:59:59 IST 2019";
 DateFormat dateFormat = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy", Locale.ROOT);

 List<OverseasTransaction> overseasTransactionList1 = createMockOverseasTransaction();

 Mockito.doReturn(overseasTransactionList1).when(overseasTransactionsStore)
 .queryOverseasTransactionsOnPPTimelineandDates(Mockito.isA(String.class), Mockito.isA(Date.class),
 Mockito.isA(Date.class));
 Mockito.when(getTransactionsForProcessorGroupActivity.getOverseasTransactions(herdDocument))
 .thenCallRealMethod();
 List<OverseasTransaction> overseasTransactionList = getTransactionsForProcessorGroupActivity
 .getOverseasTransactions(herdDocument);
 assertNotNull(overseasTransactionList);
 // assertEquals(overseasTransactionList.getPaymentProcessorID(), actual);
 

 private List<OverseasTransaction> createMockOverseasTransaction() 

 Date date = new Date();
 BigDecimal num = new BigDecimal(100001);
 List<OverseasTransaction> overseasTransactionList = new ArrayList<OverseasTransaction>();
 OverseasTransaction overseasTransaction = new OverseasTransaction();
 overseasTransaction.setPurchaseID("purchaseID");
 overseasTransaction.setSignatureID("signatureID");
 overseasTransaction.setPaymentProcessorTransactionID("paymentProcessorTransactionID");
 overseasTransaction.setType("Charge");
 overseasTransaction.setSubType("subType");
 overseasTransaction.setTransactionTimestamp(date);
 overseasTransaction.setPaymentMethod("paymentMethod");
 overseasTransaction.setTotalAmount(num);
 overseasTransaction.setOverseasAmount(num);
 overseasTransaction.setCurrency("currency");
 overseasTransaction.setMarketplaceID("marketplaceID");
 overseasTransaction.setOrderMetadata("orderMetadata");
 overseasTransaction.setDisbursementID("disbursementID");
 overseasTransaction.setReconState(1);
 overseasTransaction.setPaymentProcessorID("BillDesk");
 overseasTransaction.setRemittanceFileStatus("remittanceFileStatus");
 overseasTransaction.setCrowID("crowID");
 overseasTransaction.setSource("source");
 overseasTransactionList.add(overseasTransaction);
 return overseasTransactionList;
 

In my test file when I mock OverseasTransaction object, it gives me a NullPointerException. Do you have any suggestions about how we can mock this? All the above commented lines in my test indicates the things I tried but they still seem to throw the same error.

StackTrace of error: while executing canGetOverseasTransactiontest

N/A

java.lang.NullPointerException
at com.ingsfundflowservice.activity.GetTransactionsForProcessorGroupActivity.getOverseasTransactions(GetTransactionsForProcessorGroupActivity.java:71)
at com.ingsfundflowservice.activity.GetTransactionsForProcessorGroupActivityTest.canGetOverseasTransactiontest(GetTransactionsForProcessorGroupActivityTest.java:172)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:310)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:122)
at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:106)
at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:59)

You need to create object of Class which for which you are writing the test. i.e. GetTransactionsForProcessorGroupActivity. There is what you can do

@RunWith(MockitoJUnitRunner.class)
public class GetTransactionsForProcessorGroupActivityTest 

 @InjectMocks
 private GetTransactionsForProcessorGroupActivity getTransactionsForProcessorGroupActivity;

 @Mock
 private OverseasTransaction overseastransaction;

 @Test
 public void test() 
 Mockito.when(overseastransaction.somemethod()).thenReturn(something);
 

This will make sure that getTransactionsForProcessorGroupActivity is created and overseastransaction is injected with mock object.

Please note the class annotation @RunWith. This make sure that all the properties are injected with mock object properly. Also, you can use Mockito instead of PowerMockito.