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Mockito - NullpointerException when invoking method from Service

Hi I am trying to test the method but it returned null and I don't know why; Method should work properly but still, I have NullPointerException
#Service
public class AzureCloudStorageService implements FileService {
private final String connectionString;
private final String containerName;
private final ModelMapper modelMapper;
public AzureCloudStorageService(#Autowired PropertyResolver propertyResolver,
ModelMapper modelMapper) {
this.connectionString = propertyResolver.getProperty("azure.connection.string");
this.containerName = propertyResolver.getProperty("azure.container.name");
this.modelMapper = modelMapper;
}
public MultipartFile convertToMultipartImage(String image) {
try {
return modelMapper.map(image, MultipartFile.class);
} catch (Exception e) {
throw new BadRequestException(ErrorMessage.MULTIPART_FILE_BAD_REQUEST + image);
}
}
and the test method, maybe it`s because of final methods or something, I have no idea
#ExtendWith(SpringExtension.class)
class AzureCloudStorageServiceTest {
#Mock
private ModelMapper modelMapper;
#Mock
private AzureCloudStorageService azureCloudStorageService;
#Test
void convertToMultipartImage(){
MultipartFile multipartFile = ModelUtils.getFile();
String image = "Image";
when(modelMapper.map(image, MultipartFile.class)).thenReturn(multipartFile);
MultipartFile actual = azureCloudStorageService.convertToMultipartImage("Image");
assertEquals(multipartFile, actual);
}
}
there is stacktrace for my program. Some exceprion and error, sorry for screens in comment but i didnt see how to edit
org.opentest4j.AssertionFailedError:
Expected :org.springframework.mock.web.MockMultipartFile#441cc260
Actual :null
<Click to see difference>
at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:55)
at org.junit.jupiter.api.AssertionUtils.failNotEqual(AssertionUtils.java:62)
at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:182)
at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:177)
at org.junit.jupiter.api.Assertions.assertEquals(Assertions.java:1124)
at greencity.service.AzureCloudStorageServiceTest.convertToMultipartImage(AzureCloudStorageServiceTest.java:46)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:688)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:149)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:140)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:84)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:210)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:206)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:131)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:65)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:108)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:96)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:75)
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71)
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)

Your problems stems from the wrong way you do your mocks. In your code you do the following:
#Mock
private AzureCloudStorageService azureCloudStorageService;
Which effectively returns a mocked instance of AzureCloudStorageService. This is not what you want and need for this case, as this is what you need to test (i.e the unit under test). What you need to do though is to manually instantiate the AzureCloudStorageService by calling its constructor and passing in the mocked ModelMapper as well as PropertyResolver.

Instead of
#Mock
private ModelMapper modelMapper;
Use into the method or in #Before method:
ModelMapper modelMapper = Mockito.mock(ModelMapper.class);
It is working for me:
ServicioCalls servicioCalls = Mockito.mock(ServicioCalls.class);
EncapsulatedError<?> encapsulatedError = new EncapsulatedError<>(SpResult.SUCCESS_CODE, SpResult.OK, 0, null);
Mockito.doReturn(encapsulatedError).when(servicioCalls).obtenerCalls(anyString(), anyString(), anyLong());

It`s working properly and covering my method and constructor) Thank you akortex
#Test
void convertToMultipartImage(){
MultipartFile multipartFile = Mockito.mock(MultipartFile.class);
AzureCloudStorageService azureCloudStorageService = new AzureCloudStorageService(propertyResolver, modelMapper);
String image = "Image";
when(modelMapper.map(image, MultipartFile.class)).thenReturn(multipartFile);
assertEquals(multipartFile, azureCloudStorageService.convertToMultipartImage("Image"));
}

Ok, try with it:
Change this:
when(modelMapper.map(image, MultipartFile.class)).thenReturn(multipartFile);
By this:
Mockito.doReturn(modelMapper).when(modelMapper).map(anyString(), any());
And set to azureCloudStorageService the mockling object modelMapper previos to call:
azureCloudStorageService.setModelMapper(modelMapper);
MultipartFile actual = azureCloudStorageService.convertToMultipartImage("Image");
assertEquals(multipartFile, actual);

Ok, do you can use inheritance, creates a class dummy like it
private static class CallsRestStub extends CallsRest {
}
When CallsRest is the original class and modelMapper protected.
With it you can creates a instance of CallsRestStub instead CallSRest and sets to it the mocking object

when unit testing controller i'm getting an assertion error

i have created a basic CRUD api with spring boot.I have written test cases for the controller class,but i'm getting error when running the test.
The code's i tried is given Below
model
package com.example.crudrestapi.model;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
#Data
#Entity
#Builder
#AllArgsConstructor
#NoArgsConstructor
public class Customer {
#Id
#GeneratedValue private Long id;
private String name;
private String address;
private String phoneNumber;
private String gstin;
private float outstandingBalance;
}
CrudController
public class CrudController {
#Autowired
CustomerRepo customerRepo;
#PostMapping("/customers")
public #ResponseBody
Customer postCustomer(#RequestBody Customer customer) {
return customerRepo.save(customer);
}
#PutMapping("customers/{customerId}")
public ResponseEntity<Customer> updateCustomer(#RequestBody Customer newCustomer, #PathVariable Long customerId) {
Optional<Customer> optionalCustomer = customerRepo.findById(customerId);
if (optionalCustomer.isPresent()){
Customer c = optionalCustomer.get();
if (newCustomer.getName() != null)
c.setName(newCustomer.getName());
if (newCustomer.getGstin() != null)
c.setGstin(newCustomer.getGstin());
if (newCustomer.getPhoneNumber() != null)
c.setPhoneNumber(newCustomer.getPhoneNumber());
if (newCustomer.getAddress() != null)
c.setAddress(newCustomer.getAddress());
if (newCustomer.getOutstandingBalance() != 0.0f)
c.setOutstandingBalance(newCustomer.getOutstandingBalance());
return new ResponseEntity<>(customerRepo.save(c), HttpStatus.OK);
}else{
return new ResponseEntity<>(HttpStatus.NOT_FOUND);
}
}
#DeleteMapping("customers/{customerId}")
public String deleteCustomer(#PathVariable Long customerId) throws ResourceNotFoundException {
return customerRepo.findById(customerId)
.map(customer -> {
customerRepo.delete(customer);
return "Success";
})
.orElseThrow(() -> new ResourceNotFoundException());
}
}
CrudControllerTest
package com.example.crudrestapi.controller;
import com.example.crudrestapi.model.Customer;
import com.example.crudrestapi.repository.CustomerRepo;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import org.springframework.test.web.servlet.MockMvc;
import java.util.Arrays;
import java.util.Optional;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.Matchers.hasSize;
import static org.mockito.BDDMockito.given;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
#ExtendWith(SpringExtension.class)
#WebMvcTest(CrudController.class)
class CrudControllerTest {
#Autowired
MockMvc mockMvc;
#MockBean
CustomerRepo customerRepo;
#Test
void postCustomer() throws Exception {
Customer customer = Customer.builder().name("name").address("address").build();
given(customerRepo.save(customer));
mockMvc.perform(post("/customers")
.contentType(MediaType.APPLICATION_JSON)
.content(customer.toString())
)
.andExpect(status().isOk());
}
#Test
void deleteCustomer() throws Exception {
Customer customer = Customer.builder().name("name").address("address").build();
given(customerRepo.findById(Long.parseLong("1"))).willReturn(Optional.empty());
mockMvc.perform(delete("/customers/{customerId}", 1)
.contentType(MediaType.APPLICATION_JSON))
.andExpect(status().isOk());
}
}
Error I'm Getting for POST api test
java.lang.AssertionError: Status expected:<200> but was:<400>
Expected :200
Actual :400
<Click to see difference>
at org.springframework.test.util.AssertionErrors.fail(AssertionErrors.java:59)
at org.springframework.test.util.AssertionErrors.assertEquals(AssertionErrors.java:122)
at org.springframework.test.web.servlet.result.StatusResultMatchers.lambda$matcher$9(StatusResultMatchers.java:627)
at org.springframework.test.web.servlet.MockMvc$1.andExpect(MockMvc.java:196)
at com.example.crudrestapi.controller.CrudControllerTest.postCustomer(CrudControllerTest.java:55)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:688)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:149)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:140)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:84)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:210)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:206)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:131)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:65)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:108)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:96)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:75)
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71)
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:220)
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:53)
Suppressed: org.mockito.exceptions.misusing.UnfinishedStubbingException:
Unfinished stubbing detected here:
-> at com.example.crudrestapi.controller.CrudControllerTest.postCustomer(CrudControllerTest.java:50)
E.g. thenReturn() may be missing.
Examples of correct stubbing:
when(mock.isOk()).thenReturn(true);
when(mock.isOk()).thenThrow(exception);
doThrow(exception).when(mock).someVoidMethod();
Hints:
1. missing thenReturn()
2. you are trying to stub a final method, which is not supported
3. you are stubbing the behaviour of another mock inside before 'thenReturn' instruction is completed
at org.springframework.boot.test.mock.mockito.ResetMocksTestExecutionListener.resetMocks(ResetMocksTestExecutionListener.java:82)
at org.springframework.boot.test.mock.mockito.ResetMocksTestExecutionListener.resetMocks(ResetMocksTestExecutionListener.java:69)
at org.springframework.boot.test.mock.mockito.ResetMocksTestExecutionListener.afterTestMethod(ResetMocksTestExecutionListener.java:63)
at org.springframework.test.context.TestContextManager.afterTestMethod(TestContextManager.java:441)
at org.springframework.test.context.junit.jupiter.SpringExtension.afterEach(SpringExtension.java:205)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeAfterEachCallbacks$11(TestMethodTestDescriptor.java:253)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeAllAfterMethodsOrCallbacks$12(TestMethodTestDescriptor.java:269)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeAllAfterMethodsOrCallbacks$13(TestMethodTestDescriptor.java:269)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeAllAfterMethodsOrCallbacks(TestMethodTestDescriptor.java:268)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeAfterEachCallbacks(TestMethodTestDescriptor.java:252)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:137)
... 43 more
2020-12-27 18:23:51.851 INFO 10488 --- [extShutdownHook] o.s.s.concurrent.ThreadPoolTaskExecutor : Shutting down ExecutorService 'applicationTaskExecutor'
Process finished with exit code -1
Delete Api test case Error
java.lang.AssertionError: Status expected:<200> but was:<404> Expected
:200 Actual :404
I'm failing in the above test cases.I don't know what is the issue.I'm Just a noob in testing environment .Any Suggestion would be a great help to me.
EDIT
Post api Error
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.mockito.exceptions.misusing.UnfinishedStubbingException:
Unfinished stubbing detected here:
-> at com.example.crudrestapi.controller.CrudControllerTest.postCustomer(CrudControllerTest.java:52)
E.g. thenReturn() may be missing.
Examples of correct stubbing:
when(mock.isOk()).thenReturn(true);
when(mock.isOk()).thenThrow(exception);
doThrow(exception).when(mock).someVoidMethod();
Hints:
1. missing thenReturn()
2. you are trying to stub a final method, which is not supported
3. you are stubbing the behaviour of another mock inside before 'thenReturn' instruction is completed

I think the problem is the test. In particular, the way that you send the information in the body because you send an Object but the MockMvc needs a String with the JSON format to simulate a real request from outside of the API.
The way to fix the problem is:
#Test
void postCustomer() throws Exception {
Customer customer = Customer.builder().name("name").address("address").build();
given(customerRepo.save(customer));
mockMvc.perform(post("/customers")
.contentType(MediaType.APPLICATION_JSON)
.content(asJsonString(customer))//Call to other method to transform an object to a JSON
)
.andExpect(status().isOk());
}
private String asJsonString(final Object obj) {
try {
return new ObjectMapper().writeValueAsString(obj);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
The class ObjectMapper is from this package com.fasterxml.jackson.databind.ObjectMapper

Java Spring Boot Testing with MySQL Database

My tests for this CRUD operation in Spring Boot continue to fail where I get "java.util.NoSuchElementException: No Value Present" I understand that testCreateDemographic is creating a record, however, testFindDemographicsById is not able to find the newly created record because it is using "1L" in findById(1L) to find a record. How do I get the correct new related record Id to place in findById() argument?
package com.lizardkinghotel.demographic;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import com.lizardkinghotel.demographic.entities.DemographicEntity;
import com.lizardkinghotel.demographic.repos.DemographicRepository;
#SpringBootTest
class DemographicAppApplicationTests {
#Autowired
private DemographicRepository demoRepo;
#Test
public void testCreateDemographic() {
DemographicEntity demoEntity = new DemographicEntity();
//demoEntity.setId(1L);
demoEntity.setAge("39–47");
demoEntity.setChildren(2);
demoEntity.setCity("san jose");;
demoEntity.setCountry("costa rica");
demoEntity.setEducation("bacherlors degree");
demoEntity.setEmail("test#test.com");
demoEntity.setEmployment("yes");
demoEntity.setGender("male");
demoEntity.setGuestAmount(2);
demoEntity.setHearAbout("google search");
demoRepo.save(demoEntity);
}
#Test
public void testFindDemographicsById() {
DemographicEntity demoEntity = demoRepo.findById(1L).get();
}
//testing updating a record
#Test
public void testUpdateDemo() {
DemographicEntity demoEntity = demoRepo.findById(1L).get();
demoRepo.save(demoEntity);
}
#Test
public void testDeleteDemo() {
DemographicEntity demoEntity = demoRepo.findById(1L).get();
demoRepo.delete(demoEntity);
}
}
Below is my error:
java.util.NoSuchElementException: No value present
at java.util.Optional.get(Optional.java:135)
at com.lizardkinghotel.demographic.DemographicAppApplicationTests.testFindDemographicsById(DemographicAppApplicationTests.java:49)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:125)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:132)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:124)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:74)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:104)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:62)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:43)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:35)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:202)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:198)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:69)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.util.ArrayList.forEach(ArrayList.java:1249)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.util.ArrayList.forEach(ArrayList.java:1249)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229)
at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197)
at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:137)
at org.eclipse.jdt.internal.junit5.runner.JUnit5TestReference.run(JUnit5TestReference.java:98)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:542)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:770)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:464)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:210)

JUnit test should not depend on the other. Which means change your findById test to something like this:
#Test
public void testFindDemographicsById() {
DemographicEntity demoEntity = new DemographicEntity();
demoEntity.setAge("39–47");
demoEntity.setChildren(2);
demoEntity.setCity("san jose");;
demoEntity.setCountry("costa rica");
demoEntity.setEducation("bacherlors degree");
demoEntity.setEmail("test#test.com");
demoEntity.setEmployment("yes");
demoEntity.setGender("male");
demoEntity.setGuestAmount(2);
demoEntity.setHearAbout("google search");
DemographicEntity saved = demoRepo.save(demoEntity);
DemographicEntity demoEntity = demoRepo.findById(saved.getId()).get();
}

Try to test the Email Class with Mockito [duplicate]

This question already has answers here:
Mockito : how to verify method was called on an object created within a method?
(8 answers)
Closed 2 years ago.
I tried to test the following method sendMail
public void sendMail(Student student, String currentSubject, File file) {
String emailText = createCustomizedEmailBodyText(student, currentSubject);
String mail = student.getEmail();
String subject = "Ihr Zulassungsnachweis zum Fach: ";
sendMessage(mail, subject + currentSubject, emailText, file, file.getName());
file.deleteOnExit();
}
My test class so on
package mops.zulassung2.services;
import mops.zulassung2.model.dataobjects.Student;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;
import org.mockito.Mockito;
import org.springframework.mail.javamail.JavaMailSender;
import java.io.File;
import static org.mockito.Mockito.mock;
class EmailServiceTest {
static EmailService emailServices = mock(EmailService.class);
static EmailService emailService;
static SignatureService signatureService = mock(SignatureService.class);
#BeforeAll
static void setUp() {
JavaMailSender javaMailSender = mock(JavaMailSender.class);
emailService = new EmailService(javaMailSender, signatureService);
}
#Test
void sendMail() {
Student student = new Student("272490", "snami100#uni-duesseldorf.de", "Amin", "Snur");
String subject = "Informatik";
File file = mock(File.class);
Mockito.verify(emailServices).sendMail(student, subject, file);
}
}
In this test i just want to know if the method sendMail is called (with the params)
Im new at programming and maybe someone could help me
This is the error i got when i try to run the test, i dont know what it mean, so maybe someone could help me to make the the test running and sucess, thanks....
Wanted but not invoked:
emailService.sendMail(
mops.zulassung2.model.dataobjects.Student#327fca0d,
"Informatik",
Mock for File, hashCode: 1035729309
);
-> at mops.zulassung2.services.EmailServiceTest.sendMail(EmailServiceTest.java:31)
Actually, there were zero interactions with this mock.
Wanted but not invoked:
emailService.sendMail(
mops.zulassung2.model.dataobjects.Student#327fca0d,
"Informatik",
Mock for File, hashCode: 1035729309
);
-> at mops.zulassung2.services.EmailServiceTest.sendMail(EmailServiceTest.java:31)
Actually, there were zero interactions with this mock.
at mops.zulassung2.services.EmailServiceTest.sendMail(EmailServiceTest.java:31)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:125)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:132)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:124)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:74)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:104)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:62)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:43)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:35)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:202)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:198)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:69)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220)
at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188)
at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:99)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:79)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:75)
at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:61)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33)
at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94)
at com.sun.proxy.$Proxy2.stop(Unknown Source)
at org.gradle.api.internal.tasks.testing.worker.TestWorker.stop(TestWorker.java:132)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:182)
at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:164)
at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:412)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)
at java.base/java.lang.Thread.run(Thread.java:830)

Tests should follow the structure Given-When-Then (GWT).
In your code you have then Given and the Then but the When (emailServices.sendMail() call) is missing:
#Test
void sendMail() {
// Given
Student student = new Student("272490", "snami100#uni-duesseldorf.de", "Amin", "Snur");
String subject = "Informatik";
File file = mock(File.class);
// When
emailServices.sendMail(student, subject, file);
// Then
Mockito.verify(emailServices, times(1)).sendMail(student, subject, file);
Mockito.verify(emailServices, times(1)).sendMessage(anyString(), anyString(), anyString(), anyObject(), anyString());
}

It's a bit hard to be sure because I don't know what class the sendMail method is in.
Also, you might get yourself in trouble with setting up all your mocked variables in as class-wide variables with the use of static and #BeforeAll instead of #BeforeEach.
The basic problem with your test is that you aren't calling the method you are trying to test.
I think you are trying to do something like this:
#Test
void sendMail() {
// Given
Student student = new Student("272490", "snami100#uni-duesseldorf.de", "Amin", "Snur");
String subject = "Informatik";
File file = mock(File.class);
// When
emailServices.sendMail(student, subject, file);
// Then
Mockito.verify(something).sendMessage(eq(student), eq(subject), eq(file));
Mockito.verify(file).deleteOnExit();
}
As #jeprubio said, it will help to organize your tests in the Given-When-Then format so you are more clear on what you are assuming about your test and what you are testing.

NPE returned by a mocked function spring boot

I'm new to testing and I'm trying to learn unit testing using JUnit and spring boot and that exception popped up.
As you can see I mocked the behavior of the function I needed in the TopicSevices but I still get this NPE, I also tried to add
MockitoAnnotations.initMocks(this);
But it didn't work.
The controller code
package com.example.test.controller;
import java.util.List;
import javax.validation.Valid;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import com.example.test.Services.ExerciceServices;
import com.example.test.Services.TopicService;
import com.example.test.model.Difficulty;
import com.example.test.model.Exercice;
import com.example.test.model.Status;
import com.example.test.model.dto.ExerciceDTO;
#CrossOrigin("*")
#RestController
public class ExerciceController {
private final ExerciceServices exerciceServices;
private final TopicService topicServices;
public ExerciceController(ExerciceServices exerciceServices, TopicService topicServices) {
this.exerciceServices = exerciceServices;
this.topicServices = topicServices;
}
#GetMapping("/exercices")
public List<Exercice> allExercices() {
return exerciceServices.getAllExecices();
}
#PostMapping("/exercices")
public Exercice createExercice(#Valid #RequestBody ExerciceDTO dto) {
Exercice exercice = createExcerciceFromDto(dto);
return exerciceServices.CreateeExercice(exercice);
}
public Exercice createExcerciceFromDto(ExerciceDTO dto) {
Exercice exercice = new Exercice();
exercice.setDifficulty(dto.getDifficulty());
exercice.setImg(dto.getImg());
exercice.setStatus(dto.getStatus());
exercice.setTitle(dto.getTitle());
for (Long id : dto.getListToppicId()) {
try {
System.out.println(topicServices.getTopicById(id));
} catch (Exception e) {
e.printStackTrace();
}
}
return exercice;
}
#GetMapping("/exercices/filter")
public List<Exercice> getExeerciceByDifficulty(#RequestParam(required = false) Long id,
#RequestParam Difficulty difficulty, #RequestParam Status status) {
return exerciceServices.exercicesFilterTopic(id, difficulty, status);
}
}
The test code
package com.example.test.controller;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Optional;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mockito;
import org.mockito.junit.MockitoJUnitRunner;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.test.web.servlet.MockMvc;
import com.example.test.Services.ExerciceServices;
import com.example.test.Services.TopicService;
import com.example.test.model.Difficulty;
import com.example.test.model.Exercice;
import com.example.test.model.Status;
import com.example.test.model.Topic;
import com.example.test.model.dto.ExerciceDTO;
#RunWith(MockitoJUnitRunner.class)
#WebMvcTest
class ExerciceControllerTest {
#MockBean
private ExerciceServices exerciceServices;
#MockBean
private TopicService topicServices;
#InjectMocks
private ExerciceController exerciceController;
ExerciceDTO dto = new ExerciceDTO();
Exercice e = new Exercice();
Topic t = new Topic();
#BeforeEach
public void setUp() throws Exception {
Mockito.when(exerciceServices.getAllExecices()).thenReturn(Arrays.asList(e));
}
#Test
public void givenDTOCreateTheExercice() {
dto.setDifficulty(Difficulty.EASY);
dto.setImg("link");
dto.setStatus(Status.FINISHED);
dto.setTitle("title");
dto.setListToppicId(new HashSet<>(Arrays.asList(6L)));
e.setDifficulty(Difficulty.EASY);
e.setImg("link");
e.setStatus(Status.FINISHED);
e.setTitle("title");
t.setId(6L);
t.setTitle("romayssae");
e.setTopics(new HashSet<>(Arrays.asList(t)));
Optional<Topic> topic = Optional.of(t);
Mockito.when(topicServices.getTopicById(6L)).thenReturn(topic);
System.out.println(topicServices.getTopicById(6L));
assertEquals(e, exerciceController.createExcerciceFromDto(dto));
}
}
The Exception
java.lang.NullPointerException
at com.example.test.controller.ExerciceController.createExcerciceFromDto(ExerciceController.java:58)
at com.example.test.controller.ExerciceControllerTest.givenDTOCreateTheExercice(ExcerciceControllerTest.java:77)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:125)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:132)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:124)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:74)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:104)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:62)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:43)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:35)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:202)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:198)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:69)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229)
at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197)
at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:137)
at org.eclipse.jdt.internal.junit5.runner.JUnit5TestReference.run(JUnit5TestReference.java:89)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:541)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209)

try to use #Mock instead of #MockBean. It should be ok

I tried this and it worked for me, however, I did not understand why.
In short, I changed the #Mock instead of #MockBean as suggested by #arbuzov. Then I got this exception:
java.lang.IllegalStateException: Failed to load ApplicationContext
To solve this I added this two annotations #SpringBootTest and #AutoConfigureMockMvc. Then I tried to test another method using the MockMvc there again the mocked behavior was ignored somehow, so I changed back to #MockBean which worked.
I would be happy to receive any comments and explanations of how it works, if anyone has any.
package com.example.test.controller;
import static org.hamcrest.CoreMatchers.is;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Optional;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.Mockito;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.test.web.servlet.MockMvc;
import com.example.test.Services.ExerciceServices;
import com.example.test.Services.TopicService;
import com.example.test.model.Difficulty;
import com.example.test.model.Exercice;
import com.example.test.model.Status;
import com.example.test.model.Topic;
import com.example.test.model.dto.ExerciceDTO;
#RunWith(SpringRunner.class)
#SpringBootTest
#AutoConfigureMockMvc
class ExerciceControllerTest {
#Autowired
private MockMvc mockMvc;
#MockBean
private ExerciceServices exerciceServices;
#Mock
private TopicService topicServices;
#InjectMocks
private ExerciceController exerciceController;
ExerciceDTO dto = new ExerciceDTO();
Exercice e = new Exercice();
Topic t = new Topic();
#BeforeEach
public void setUp() throws Exception {
}
#Test
public void givenDTOCreateTheExercice() {
assertEquals(e, exerciceController.createExcerciceFromDto(dto));
}
#Test
public void eznekfnzre() throws Exception {
dto.setDifficulty(Difficulty.EASY);
dto.setImg("link");
dto.setStatus(Status.FINISHED);
dto.setTitle("title");
dto.setListToppicId(new HashSet<>(Arrays.asList(6L)));
e.setDifficulty(Difficulty.EASY);
e.setImg("link");
e.setStatus(Status.FINISHED);
e.setTitle("title");
t.setId(6L);
t.setTitle("romayssae");
e.setTopics(new HashSet<>(Arrays.asList(t)));
Optional<Topic> topic = Optional.of(t);
Mockito.when(topicServices.getTopicById(6L)).thenReturn(topic);
Mockito.when(exerciceServices.getAllExecices()).thenReturn(Arrays.asList(e));
mockMvc.perform(get("/exercices/").contentType(MediaType.APPLICATION_JSON)).andExpect(status().isOk())
.andExpect(jsonPath("$[0].title", is(e.getTitle())));
}
}