Spring test service class mocking utility class- Junit and Mockito - java

I want to write test cases for service layer of spring framework using Junit + Mockito.
How to call the actual service layer method using my ServiceTest class, If i mock the ServiceTest class then it's object wont execute the actual service method code because it wont get the object to call it's methods and if I try with the Spy still it was not working, I tried this example
still I not able to execute the test cases.
MyService.java
#Service
public class MyService{
#Autowired
Utility utility;
public String showResult(){
String result = utility.getName();
return result;
}
}
MyServiceTest.java
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(loader=AnnotationConfigWebContextLoader.class)
#WebAppConfiguration
public class MyServiceTest {
#Autowired
MyService myService;
#Autowired
Utility utility;
#Test
public void testShowResult() throws Exception {
assertEquals("Test",myService.showResult());
}
#Configuration
static class MykServiceTestContextConfiguration {
#Bean
public MyService myService() {
return new MyService();
}
#Bean
public Utility utility() {
return Mockito.mock(Utility.class);
}
}
}

You have to first mock the Utility class and then have to invoke it before calling your #Test using MockitoAnnotations.initMocks(this) as follows:
MyServiceTest.java
import static org.mockito.Mockito.when;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.AnnotationConfigWebContextLoader;
import org.springframework.test.context.web.WebAppConfiguration;
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(loader = AnnotationConfigWebContextLoader.class)
#WebAppConfiguration
public class MyServiceTest {
#InjectMocks
private MyService myService;
#Mock
private Utility utility;
#Before
public void setupMock() {
MockitoAnnotations.initMocks(this);
}
#Test
public void testShowResult() throws Exception {
when(utility.getName()).thenReturn("Test");
Assert.assertEquals("Test", myService.showResult());
}
#Configuration
static class MykServiceTestContextConfiguration {
#Bean
public MyService myService() {
return new MyService();
}
#Bean
public Utility utility() {
return new Utility();
}
}
}
MyService.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
#Service
public class MyService {
#Autowired
private Utility utility;
public String showResult() {
String result = utility.getName();
return result;
}
}
Utility.java
import org.springframework.stereotype.Component;
#Component
public class Utility {
public String getName() {
return "hello";
}
}

Make use of #Spy
When spy is called, then actual method of real object is called.
https://www.tutorialspoint.com/mockito/mockito_spying.htm
please go through the tutorial
This worked for me
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration
#WebAppConfiguration
public class MyServiceTest {
#Spy
MyService myService;
#Test
public void testShowResult() throws Exception {
assertEquals("Test",myService.showResult());
}
#Service
public class MyService{
public String showResult(){
return "Test";
}
}
}
still having issues share the spring version you are using

How about using #MockBean? It suits Spring + JUnit and, probably you need to implement mock behavior.
I guess that Utility.getName() return "Test" in the test case.
The following is the test code I tried.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(loader = AnnotationConfigWebContextLoader.class)
#WebAppConfiguration
public class MyServiceTest {
#Autowired
MyService myService;
#MockBean
Utility utility;
#Test
public void testShowResult() throws Exception {
Mockito.when(utility.getName()).thenReturn("Test");
assertEquals("Test", myService.showResult());
}
#Configuration
static class MykServiceTestContextConfiguration {
#Bean
public MyService myService() {
return new MyService();
}
}
}

Related

Mockito: How to Mock objects in a Spy

The application runs in JEE environment.
I wish inject a Spy into a bean under test.
The Spy object has also some beans inside that should be injected. How can inject mocks of those beans into the Spy?
This is the usecase:
package testinject2;
import javax.inject.Inject;
public class ABean {
#Inject
BBean b;
public void print() {
System.out.println("Hi, I'm ABean");
b.print();
}
}
package testinject2;
import javax.inject.Inject;
public class BBean {
#Inject
CBean c;
public void print() {
System.out.println("Hi, I'm BBean");
c.print();
}
}
package testinject2;
public class CBean {
public void print() {
System.out.println("Hi, I'm CBean");
}
}
package testinject2;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Spy;
import org.mockito.runners.MockitoJUnitRunner;
#RunWith(MockitoJUnitRunner.class)
public class ABeanTest {
#Spy
CBean c = new CBean();
#Spy
BBean b = new BBean();
#InjectMocks
ABean beanUnderTest;
#Test
public void test() {
beanUnderTest.print();
}
}
I'm expect to obtain
Hi, I'm ABean
Hi, I'm BBean
Hi, I'm CBean
But instead I have a null ponter exception because CBean is not injected into BBean.
Which is the correct way to Inject a Spy object into another Spy ?
You need to define to which object mocks should be injected via #InjectMocks annotation, but it does not work together with #Spy annotation. See mockito issue.
There is the simplest solution to use Mockito.spy instead of #Spy together with #InjectMocks:
#InjectMocks
BBean b = Mockito.spy(new BBean());
Full test code:
#RunWith(MockitoJUnitRunner.class)
public class ConfigTestObject {
#Spy
CBean c = new CBean();
#InjectMocks
BBean b = Mockito.spy(new BBean());
#InjectMocks
ABean beanUnderTest;
#Test
public void test() {
beanUnderTest.print();
//verify that mocks is working
verify(c, atLeast(1)).print();
verify(b, atLeast(1)).print();
}
}

How do I make Autowired work inside a Configuration class?

I'm trying to autowire an attribute (myService) which is tagged as a #Service, inside a #Configuration class, but I get a NullPointer.
If instead, I autowire myService in non-configuration classes, I have no issues.
Here's the #Service I'm having issues autowiring:
package com.myapp.resources;
#Service
class MyService {
public List<String> getRoutingKeys() {
List<String> routingKeys;
//Do stuff
return routingKeys;
}
public String aMethod() {
return "hello";
}
}
Here's the #Configuration class where I can't autowire the Service
package com.myapp.messaging;
import com.myapp.resources;
import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.Queue;
import org.springframework.amqp.core.TopicExchange;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.List;
#Configuration
public class RabbitConfiguration {
private List<String> routingKeys = writeRoutingKeys();
#Autowired
private MyService myService;
private List<String> writeRoutingKeys() {
boolean test = myService == null;
System.out.println("is the service null? " + test); //output: true!!!
return myService.getRoutingKeys(); //here I get a NullPointer
}
//Methods with bean declarations for RabbitMQ
}
If it helps, here's my mainclass:
package com.myapp;
import com.myapp.resources;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import java.util.List;
#SpringBootApplication
public class Application {
public static void main(String[] args) {
ConfigurableApplicationContext appContext = SpringApplication.run(Application.class, args);
MyService myService = (MyService) appContext.getBean(MyService.class);
boolean test = myService == null;
System.out.println("is the service null? " + test); //output: false
//Do stuff
}
}
If it helps, here's a different class (a #RestController) where I'm able to autowire the service
package com.myapp.resources;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
#RestController
public class MyController {
#Autowired
private MyService myService;
#GetMapping("/endpoint")
public String myRestMethod() {
boolean test = myService == null;
System.out.println("is the service null? " + test); //output: false
return myService.aMethod();
}
}
I've also tried adding the #ComponentScan in the Configuration class, but I still get a NullPointer
package com.myapp.messaging;
//list of imports...
#Configuration
#ComponentScan("com.myapp.demo")
public class RabbitConfiguration {
#Autowired
private MyService myService;
//...
}
Spring will only inject the dependencies after or when a bean is instantiated (Depending if constructor injection is used or not). However , you are now accessing the dependency MyService during the field initialisation which happens before initialising a bean .Hence , it cannot access MyService during field initialisation as it is not injected yet.
You can simply fix it by changing to use constructor injection and initialise routingKeys inside a constructor at the same time :
#Configuration
public class RabbitConfiguration {
private List<String> routingKeys ;
private MyService myService;
#Autowired
public RabbitConfiguration(MyService myService){
this.myService = myService
this.routingKeys = writeRoutingKeys();
}
private List<String> writeRoutingKeys() {
return myService.getRoutingKeys();
}
}
Or simply :
#Autowired
public RabbitConfiguration(MyService myService){
this.myService = myService
this.routingKeys = myService.getRoutingKeys();
}
I would suggest injecting the service through any #Bean creation method that needs it:
#Bean
public MyBean create(MyService myService)
and then pass the service into the writeRoutingKeys(MyService myService) method to process it accordingly.
Per documentation:
#Configuration classes are processed quite early during the
initialization of the context and forcing a dependency to be injected
this way may lead to unexpected early initialization. Whenever
possible, resort to parameter-based injection as in the example above.

How to load the properties from application.properties in Mockito test

I am trying to write a unit test case to test the method, but I encounter a problem.
here is the sample code:
MyService1
#Service
public class MyService1 {
#Autowired
private ServiceProperties serviceProperties;
public void getMyLanguage(){
String language = serviceProperties.getLocale().getLanguage();
printSomething(language);
}
private void printSomething(String input){
System.out.print("your current language is " + input);
}
}
ServiceProperties
import org.springframework.boot.context.properties.ConfigurationProperties;
import java.util.Locale;
#ConfigurationProperties(prefix = "conversation")
public class ServiceProperties {
private ServiceProperties(){};
private Locale locale;
public Locale getLocale(){
return locale;
}
}
application.properties
conversation.locale=en_US
Here is my test case:
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
#RunWith(MockitoJUnitRunner.class)
public class MyService1Test {
#Mock
private ServiceProperties serviceProperties;
#InjectMocks
private MyService1 myService1;
#Test
public void getMyLanguage(){
when(serviceProperties.getLocale().getLanguage()).thenReturn("EN");
myService1.getMyLanguage();
verify(myService1).getMyLanguage();
}
}
the test will trigger nullpointerexception, because the properties for locale are not loaded in test, if I don't want to start the server(use #SpringBootTest annotation) to load the context, is there any way to solve this problem, can anyone help?
The problem is at this line:
when(serviceProperties.getLocale().getLanguage()).thenReturn("EN");
Because serviceProperties is mocked, serviceProperties.getLocale() is equal to null. So you get NullPointerException when serviceProperties.getLocale().getLanguage() is called.
One workaround would be as follows:
#RunWith(MockitoJUnitRunner.class)
public class MyService1Test {
#Mock
private ServiceProperties serviceProperties;
#InjectMocks
private MyService1 myService1;
#Test
public void getMyLanguage(){
when(serviceProperties.getLocale()).thenReturn(new Locale("EN"));
myService1.getMyLanguage();
verify(myService1).getMyLanguage();
}
}
Field injection is not convenient for testing. You can use constructor injection
#Service
public class MyService {
private final ServiceProperties serviceProperties;
#Autowired
public MyService(ServiceProperties serviceProperties) {
this.serviceProperties = serviceProperties;
}
//...
}
And then you will be able to inject mocks before each test
#RunWith(MockitoJUnitRunner.class)
public class MyService1Test {
#Mock
private ServiceProperties serviceProperties;
private MyService1 myService1;
#Before
public void createService(){
myService1 = new MyService1(serviceProperties);
}
}

Create #MockBean with qualifier by annotating class?

In my Spring Boot test I'm using 2 mock beans with different qualifiers:
#RunWith(SpringRunner.class)
#SpringBootTest
class HohoTest {
#MockBean #Qualifier("haha") IHaha ahaha;
#MockBean #Qualifier("hoho") IHaha ohoho;
}
Since I'm not using these beans explicitly, I would rather move them away from the class body, as the #MockBean annotation is now repeatable:
#RunWith(SpringRunner.class)
#SpringBootTest
#MockBean(IHaha.class)
#MockBean(IHaha.class)
class HohoTest {}
However, I need to pass in a qualifier as well, since they have the same type. Any idea on how I can achieve that?
Because using annotation #Qualifier means choose bean by name, so you can set up a name for a mock with code like this:
#ExtendWith(SpringExtension.class)
#ContextConfiguration(classes = {JsonMapperConfig.class})
public class IntegrationFlowTest {
#MockBean(name = "s3MessageRepository")
private S3Repository s3MessageRepository;
// etc
If it is okay to move the mock definition completely out of the test class, you could also create the mocks in a separate #Configuration class:
#Configuration
public class MockConfiguration
{
#Bean #Qualifier("haha")
public IHaha ahaha() {
return Mockito.mock(IHaha.class);
}
#Bean #Qualifier("hoho")
public IHaha ohoho() {
return Mockito.mock(IHaha.class);
}
}
When declaring #MockBean at the class level, there is currently no support for providing a qualifier.
If you would like to have such support, I suggest you request it in the Spring Boot issue tracker.
Otherwise, you will need to continue declaring #MockBean on fields alongside #Qualifier.
I had a similar requirement of injecting mocked service beans with #Order annotation. I also needed to verify the invocation count of service functions. Below is my implementation. It might help someone.
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mockito;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.annotation.Order;
import org.springframework.test.context.junit4.SpringRunner;
#RunWith(SpringRunner.class)
#SpringBootTest
public class ServiceNameTest {
#Autowired private ServiceName serviceName;
// Important: Used to reset interaction count of our static
// bean objects before every test.
#Before
public void reset_mockito_interactions() {
Mockito.clearInvocations(MockServicesConfig.bean1);
Mockito.clearInvocations(MockServicesConfig.bean2);
}
#Configuration
public static class MockServicesConfig {
public static InterfaceName bean1;
public static InterfaceName bean2;
#Bean
#Order(1)
public InterfaceName bean1() {
bean1 = Mockito.mock(InterfaceName.class);
// Common when() stubbing
return bean1;
}
#Bean
#Order(2)
public InterfaceName vmpAdapter() {
bean2 = Mockito.mock(InterfaceName.class);
// Common when() stubbing
return bean2;
}
}
#Test
public void test_functionName_mock_invocation1() {
// Arrange --> Act --> Assert
// nullify other functions custom when() stub.
// updating this functions custom when() stub.
verify(MockServicesConfig.bean1, times(1)).functionName("");
}
#Test
public void test_functionName_mock_invocation2() {
// Arrange --> Act --> Assert
// nullify other functions custom when() stub.
// updating this functions custom when() stub.
verify(MockServicesConfig.bean1, times(1)).functionName("");
}
}
This should now work
#SpringBootTest(
classes = Some.class
)
#MockBean(name = BEAN_NAME, classes = TheBeanClass.class)
#MockBean(name = BEAN_NAME_2, classes = TheBeanClass.class)
class SomeTest {
private final Some some;
#Autowired
SomeTest(Some some) {
this.some = some;
}
}
Please note, if you need to use any of the mocked beans, you will have to put the #Qualifier in the constructor, for example
private final TheBeanClass theBeanclass;
private final Some some;
#Autowired
SomeTest(Some some, #Qualifier(BEAN_NAME) TheBeanClass theBeanClass) {
this.some = some;
this.theBeanClass = theBeanClass;
}

Nullpointer when using #Autowire

I want to create a DAO object by dependency injection (#Autowire) but unfortunately, this DAO object is never created and hence a Nullpointer exception is thrown.
This is my DAO implementation:
package com.sample.dao.service;
#Component
public class OrderServiceImpl implements OrderService {
private final OrderRepository orderRepository;
#Autowired
OrderServiceImpl(OrderRepository orderRepository) {
this.orderRepository = orderRepository;
}
#Override
public void save(Order order) {
return orderRepository.save(order);
}
The class where the Nullpointer exception is caused:
package com.sample.dispatcher;
#Component
public class OrderDispatcher {
private final OrderServiceImpl orderServiceImpl;
#Autowired
public OrderDispatcher(OrderServiceImpl orderServiceImpl) {
this.orderServiceImpl = orderServiceImpl;
}
public void createOrder(Order order) {
orderServiceImpl.save(order)); // --> Nullpointer
My entry class:
package com.sample;
#SpringBootApplication
#ComponentScan(basePackages = { "com.sample" , "com.webservice"})
#EnableJpaRepositories(basePackages = "com.sample.dao.repository")
public class Application {
public static void main(final String[] args) {
SpringApplication.run(Application.class, args);
I think you should change your constructor to have an argument type of interface rather than a concrete implementation. So something like this -
#Component
public class OrderDispatcher {
private final OrderService orderServiceImpl;
#Autowired
public OrderDispatcher(OrderService orderServiceImpl) {
this.orderServiceImpl = orderServiceImpl;
}
When you add the #component notation on OrderServiceImpl, Spring creates proxy for that class and it can be autowired by interface.
Maybe you forgot the #annotation configuration. Try adding this class and also you scan your entities: EntityScan
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
#Configuration
#EntityScan("com.sample.model") // Your model package
#ComponentScan(basePackages = { "com.sample" , "com.webservice"})
#EnableJpaRepositories(basePackages = "com.sample.dao.repository")
public class RepositoryConfig {
}

Categories

Resources