In older Spring MVC apps, where you'd specify application.xml and declare your app's beans so that Spring DI could instantiate them and wire them together, you might have something like this:
<bean id="chargeFactory" class="com.example.myapp.ChargeFactory" />
<bean id="paymentService" class="com.example.myapp.DefaultPaymentService">
<ref id="chargeFactory"/>
</bean>
<bean id="chargeAuditor" class="com.example.myapp.ChargeAuditor">
<ref id="chargeFactory"/>
</bean>
Which might help wire up the following code:
public interface PaymentService {
public void makePayment(Payment payment);
}
public class DefaultPaymentService implements PaymentService {
#Autowired
private ChargeFactory chargeFactory;
#Override
public void makePayment(Payment payment, String key) {
Charge charge = chargeFactory.createCharge(key);
charge.doCharge(payment);
}
}
public class ChargeAuditor {
#Autowired
private ChargeFactory chargeFactory;
public void auditAllCharges(String key) {
List<Charge> charges = chargeFactory.getAllCharges(key);
// blah whatever
}
}
How do you accomplish the same bean wiring in Spring Boot with the #Configuration class? For example:
#Configuration
public class MyAppInjector {
#Bean
public ChargeFactory chargeFactory() {
return new ChargeFactory();
}
#Bean
public PaymentService paymentService() {
return new DefaultPaymentService(chargeFactory());
}
#Bean
public ChargeAuditor chargeAuditor() {
return new ChargeAuditor(chargeFactory());
}
}
This might work but introduces some issues:
It would force me to have to write value constructors for all my classes, which goes against everything I see in literally every tutorial/article I've come across. Plus, if I had to do that, then there's no real value to #Autowired anyways...
At this point I'm essentially doing "DIY DI", which is OK, except I'm trying to deliberately use Spring DI :-)
Every time I call chargeFactory() I'm getting a new (prototype-style) ChargeFactory instance. Maybe I want a singleton. Using this approach I have to hand-roll my own singleton implementation.
Sure, I can do all of this, but I feel like I'm flagrantly misusing/misunderstanding how #Configuration is supposed to be used, because it seems like I'm introducing a whole lot of DIY/homegrown code to solve something Spring DI should be able to do for me.
How would I reference the chargeFactory bean and wire it into both the "provider methods" for the paymentService and chargeAuditor beans? Again, looking for the Java-based #Configuration solution instead of writing an XML document to define the wirings.
I found this article which seems to be the only tutorial/documentation (surprisingly) on wiring Spring Boot apps via #Configuration (which leads me to believe there might be other/better methods...), but it does not address:
How to specify singleton vs prototype bean instantiation patterns
If multiple instances of a bean-class exist, how do I specify which instance gets wired into which dependency?
How do I get around not defining value constructors for all my classes, and just let Spring/#Autowired inject fields automagically?
When you call chargeFactory() , spring won't create new instance everytime. Give it a try and see. Same object will be returned. Anyways
You can do something like this.
#Bean
public PaymentService paymentService(ChargeFactory chargeFactory) { return new DefaultPaymentService(chargeFactory); }
How to autowire a generic bean in spring?
I have a dao implement as follows:
#Transactional
public class GenericDaoImpl<T> implements IGenericDao<T>
{
private Class<T> entityClass;
#Autowired
private SessionFactory sessionFactory;
public GenericDaoImpl(Class<T> clazz) {
this.entityClass = clazz;
}
...
}
Now I want to autowired the DaoImpl like this:
#Autowired
GenericDaoImpl<XXXEntity> xxxEntityDao;
I config in the spring xml:
<bean id="xxxEntityDao" class="XXX.GenericDaoImpl">
<constructor-arg name="clazz">
<value>xxx.dao.model.xxxEntity</value>
</constructor-arg>
<property name="sessionFactory" ref="sessionFactory"/>
</bean>
But I doesn't work, How should I config it? or a good practice about generic Dao implement?
Work with your interfaces instead of implementations
Do not use #Transactional in your persistent layer as it is much more likely that it belongs to your service layer.
Those being said, it might make more sense to extend the generic dao and autowire that. An example would be something like :
public interface UserDao extends GenericDao<User> {
User getUsersByNameAndSurname(String name, String surname);
... // More business related methods
}
public class UserDaoImpl implements UserDao {
User getUsersByNameAndSurname(String name, String surname);
{
... // Implementations of methods beyond the capabilities of a generic dao
}
...
}
#Autowired
private UserDao userDao; // Now use directly the dao you need
But if you really really want to use it that way you have to declare a qualifier :
#Autowired
#Qualifier("MyBean")
private ClassWithGeneric<MyBean> autowirable;
There is an alternative way.
I change the GenericDaoImpl<T> to a common class without Generic but use the generic in function
level, and the entityClass can be configured in spring xml.
Currently, I'm writing some webapp using Spring framework. For all #RestController APIs, I use Jackson to generate Json objects.
The #RestController looks like
#RestController
#RequestMapping("/api")
public class SomeAPI {
#RequestMapping(method = RequestMethod.GET)
public A getA() {
A a = new A();
return a;
}
}
But there are circular dependency problems when two objects have bi-direction-reference. For example, there are two POJO classes as follows:
class A {
private B b;
// constructor
...
// setters and getters.
...
}
class B {
private A a;
// constructor
...
// setters and getters.
...
}
I can solve it easily by this way, using annotations: http://java.dzone.com/articles/circular-dependencies-jackson
But that's not my point.
Now, I cannot change the code of A and B classes, so that I cannot use any annotations in them. Then how can I solve this problem without using annotations?
Thanks in advance for any advice!
Finally, I've found the Mixin Annotations to solve the circular without touching the existing POJO.
There is a reference of Minin Annotations here: http://wiki.fasterxml.com/JacksonMixInAnnotations
The following is a brief steps to use Mixin:
Add ObjectMapper to your web-spring-servlet.xml
<bean id="myFrontObjectMapper" class="my.anying.web.MyObjectMapper"></bean>
<mvc:annotation-driven>
<mvc:message-converters>
<bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
<property name="objectMapper" ref="myObjectMapper"></property>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
Implement MyObjectMapper
public class MyObjectMapper extends ObjectMapper {
public MyObjectMapper() {
this.registerModule(new MixinModule());
}
}
Implement MixinModule
public class MixinModule extends SimpleModule {
private static final long serialVersionUID = 8115282493071814233L;
public MixinModule() {
super("MixinModule", new Version(1, 0, 0, "SNAPSHOT", "me.anying",
"web"));
}
public void setupModule(SetupContext context) {
context.setMixInAnnotations(Target.class, TargetMixin.class);
}
}
Done.
Now all annotations on TargetMixin class will be applied to Target class.
I'm using Spring Roo and want to access a bean within of Controller class which has following configuration in applicationContext.xml:
<bean class="com.reservation.jobs.Configuration" id="jobsConfiguration" autowire="byType">
<property name="skipWeeks" value="4" />
</bean>
The configuration class itself is:
package com.reservation.jobs;
public class Configuration {
private int skipWeeks;
public void setSkipWeeks(int value) {
System.out.println("SkipWeeks set auf: " + value);
this.skipWeeks = value;
}
public int getSkipWeeks() {
return this.skipWeeks;
}
}
In my Controller I thought that a simple Autowired annotation should do the job
public class SomeController extends Controller {
#Autowired
private com.reservation.jobs.Configuration config;
}
During startup Spring prints the message within the setSkipWeeks method. Unfortunately whenever I call config.getSkipWeeks() within the controller it returns 0.
Have I to use the getBean method of the ApplicationContext instance or is there some better way?
autowire="byType" is redundant. It indicates that fields of the Configuration class should be autowired, and you have just one primitive. So remove that attribute.
Apart from that, config.getSkipWeeks() must return 4 unless:
you are using a different instance (made by you with new)
you have called the setter somewhere with a value of 0
I would like to inject a Mockito mock object into a Spring (3+) bean for the purposes of unit testing with JUnit. My bean dependencies are currently injected by using the #Autowired annotation on private member fields.
I have considered using ReflectionTestUtils.setField but the bean instance that I wish to inject is actually a proxy and hence does not declare the private member fields of the target class. I do not wish to create a public setter to the dependency as I will then be modifying my interface purely for the purposes of testing.
I have followed some advice given by the Spring community but the mock does not get created and the auto-wiring fails:
<bean id="dao" class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="com.package.Dao" />
</bean>
The error I currently encounter is as follows:
...
Caused by: org...NoSuchBeanDefinitionException:
No matching bean of type [com.package.Dao] found for dependency:
expected at least 1 bean which qualifies as autowire candidate for this dependency.
Dependency annotations: {
#org...Autowired(required=true),
#org...Qualifier(value=dao)
}
at org...DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(D...y.java:901)
at org...DefaultListableBeanFactory.doResolveDependency(D...y.java:770)
If I set the constructor-arg value to something invalid no error occurs when starting the application context.
The best way is:
<bean id="dao" class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="com.package.Dao" />
</bean>
Update
In the context file this mock must be listed before any autowired field depending on it is declared.
#InjectMocks
private MyTestObject testObject;
#Mock
private MyDependentObject mockedObject;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
}
This will inject any mocked objects into the test class. In this case it will inject mockedObject into the testObject. This was mentioned above but here is the code.
I have a very simple solution using Spring Java Config and Mockito:
#Configuration
public class TestConfig {
#Mock BeanA beanA;
#Mock BeanB beanB;
public TestConfig() {
MockitoAnnotations.initMocks(this); //This is a key
}
//You basically generate getters and add #Bean annotation everywhere
#Bean
public BeanA getBeanA() {
return beanA;
}
#Bean
public BeanB getBeanB() {
return beanB;
}
}
Given:
#Service
public class MyService {
#Autowired
private MyDAO myDAO;
// etc
}
You can have the class that is being tested loaded via autowiring, mock the dependency with Mockito, and then use Spring's ReflectionTestUtils to inject the mock into the class being tested.
#ContextConfiguration(classes = { MvcConfiguration.class })
#RunWith(SpringJUnit4ClassRunner.class)
public class MyServiceTest {
#Autowired
private MyService myService;
private MyDAO myDAOMock;
#Before
public void before() {
myDAOMock = Mockito.mock(MyDAO.class);
ReflectionTestUtils.setField(myService, "myDAO", myDAOMock);
}
// etc
}
Please note that before Spring 4.3.1, this method won't work with services behind a proxy (annotated with #Transactional, or Cacheable, for example). This has been fixed by SPR-14050.
For earlier versions, a solution is to unwrap the proxy, as described there: Transactional annotation avoids services being mocked (which is what ReflectionTestUtils.setField does by default now)
If you're using Spring Boot 1.4, it has an awesome way of doing this. Just use new brand #SpringBootTest on your class and #MockBean on the field and Spring Boot will create a mock of this type and it will inject it into the context (instead of injecting the original one):
#RunWith(SpringRunner.class)
#SpringBootTest
public class MyTests {
#MockBean
private RemoteService remoteService;
#Autowired
private Reverser reverser;
#Test
public void exampleTest() {
// RemoteService has been injected into the reverser bean
given(this.remoteService.someCall()).willReturn("mock");
String reverse = reverser.reverseSomeCall();
assertThat(reverse).isEqualTo("kcom");
}
}
On the other hand, if you're not using Spring Boot or are you using a previous version, you'll have to do a bit more work:
Create a #Configuration bean that injects your mocks into Spring context:
#Configuration
#Profile("useMocks")
public class MockConfigurer {
#Bean
#Primary
public MyBean myBeanSpy() {
return mock(MyBean.class);
}
}
Using #Primary annotation you're telling spring that this bean has priority if no qualifier are specified.
Make sure you annotate the class with #Profile("useMocks") in order to control which classes will use the mock and which ones will use the real bean.
Finally, in your test, activate userMocks profile:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = {Application.class})
#WebIntegrationTest
#ActiveProfiles(profiles={"useMocks"})
public class YourIntegrationTestIT {
#Inject
private MyBean myBean; //It will be the mock!
#Test
public void test() {
....
}
}
If you don't want to use the mock but the real bean, just don't activate useMocks profile:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = {Application.class})
#WebIntegrationTest
public class AnotherIntegrationTestIT {
#Inject
private MyBean myBean; //It will be the real implementation!
#Test
public void test() {
....
}
}
Since 1.8.3 Mockito has #InjectMocks - this is incredibly useful. My JUnit tests are #RunWith the MockitoJUnitRunner and I build #Mock objects that satisfy all the dependencies for the class being tested, which are all injected when the private member is annotated with #InjectMocks.
I #RunWith the SpringJUnit4Runner for integration tests only now.
I will note that it does not seem to be able to inject List<T> in the same manner as Spring. It looks only for a Mock object that satisfies the List, and will not inject a list of Mock objects. The workaround for me was to use a #Spy against a manually instantiated list, and manually .add the mock object(s) to that list for unit testing. Maybe that was intentional, because it certainly forced me to pay close attention to what was being mocked together.
Update: There are now better, cleaner solutions to this problem. Please consider the other answers first.
I eventually found an answer to this by ronen on his blog. The problem I was having is due to the method Mockito.mock(Class c) declaring a return type of Object. Consequently Spring is unable to infer the bean type from the factory method return type.
Ronen's solution is to create a FactoryBean implementation that returns mocks. The FactoryBean interface allows Spring to query the type of objects created by the factory bean.
My mocked bean definition now looks like:
<bean id="mockDaoFactory" name="dao" class="com.package.test.MocksFactory">
<property name="type" value="com.package.Dao" />
</bean>
As of Spring 3.2, this is no longer an issue. Spring now supports Autowiring of the results of generic factory methods. See the section entitled "Generic Factory Methods" in this blog post: http://spring.io/blog/2012/11/07/spring-framework-3-2-rc1-new-testing-features/.
The key point is:
In Spring 3.2, generic return types for factory methods are now
properly inferred, and autowiring by type for mocks should work as
expected. As a result, custom work-arounds such as a
MockitoFactoryBean, EasyMockFactoryBean, or Springockito are likely no
longer necessary.
Which means this should work out of the box:
<bean id="dao" class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="com.package.Dao" />
</bean>
If you're using spring >= 3.0, try using Springs #Configuration annotation to define part of the application context
#Configuration
#ImportResource("com/blah/blurk/rest-of-config.xml")
public class DaoTestConfiguration {
#Bean
public ApplicationService applicationService() {
return mock(ApplicationService.class);
}
}
If you don't want to use the #ImportResource, it can be done the other way around too:
<beans>
<!-- rest of your config -->
<!-- the container recognize this as a Configuration and adds it's beans
to the container -->
<bean class="com.package.DaoTestConfiguration"/>
</beans>
For more information, have a look at spring-framework-reference : Java-based container configuration
Below code works with autowiring - it is not the shortest version but useful when it should work only with standard spring/mockito jars.
<bean id="dao" class="org.springframework.aop.framework.ProxyFactoryBean">
<property name="target"> <bean class="org.mockito.Mockito" factory-method="mock"> <constructor-arg value="com.package.Dao" /> </bean> </property>
<property name="proxyInterfaces"> <value>com.package.Dao</value> </property>
</bean>
Perhaps not the perfect solution, but I tend not to use spring to do DI for unit tests. the dependencies for a single bean (the class under test) usually aren't overly complex so I just do the injection directly in the test code.
I can do the following using Mockito:
<bean id="stateMachine" class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="com.abcd.StateMachine"/>
</bean>
Posting a few examples based on the above approaches
With Spring:
#ContextConfiguration(locations = { "classpath:context.xml" })
#RunWith(SpringJUnit4ClassRunner.class)
public class TestServiceTest {
#InjectMocks
private TestService testService;
#Mock
private TestService2 testService2;
}
Without Spring:
#RunWith(MockitoJUnitRunner.class)
public class TestServiceTest {
#InjectMocks
private TestService testService = new TestServiceImpl();
#Mock
private TestService2 testService2;
}
Update - new answer here: https://stackoverflow.com/a/19454282/411229. This answer only applies to those on Spring versions before 3.2.
I've looked for a while for a more definitive solution to this. This blog post seems to cover all my needs and doesn't rely on ordering of bean declarations. All credit to Mattias Severson. http://www.jayway.com/2011/11/30/spring-integration-tests-part-i-creating-mock-objects/
Basically, implement a FactoryBean
package com.jayway.springmock;
import org.mockito.Mockito;
import org.springframework.beans.factory.FactoryBean;
/**
* A {#link FactoryBean} for creating mocked beans based on Mockito so that they
* can be {#link #Autowired} into Spring test configurations.
*
* #author Mattias Severson, Jayway
*
* #see FactoryBean
* #see org.mockito.Mockito
*/
public class MockitoFactoryBean<T> implements FactoryBean<T> {
private Class<T> classToBeMocked;
/**
* Creates a Mockito mock instance of the provided class.
* #param classToBeMocked The class to be mocked.
*/
public MockitoFactoryBean(Class<T> classToBeMocked) {
this.classToBeMocked = classToBeMocked;
}
#Override
public T getObject() throws Exception {
return Mockito.mock(classToBeMocked);
}
#Override
public Class<?> getObjectType() {
return classToBeMocked;
}
#Override
public boolean isSingleton() {
return true;
}
}
Next update your spring config with the following:
<beans...>
<context:component-scan base-package="com.jayway.example"/>
<bean id="someDependencyMock" class="com.jayway.springmock.MockitoFactoryBean">
<constructor-arg name="classToBeMocked" value="com.jayway.example.SomeDependency" />
</bean>
</beans>
I use a combination of the approach used in answer by Markus T and a simple helper implementation of ImportBeanDefinitionRegistrar that looks for a custom annotation (#MockedBeans) in which one can specify which classes are to be mocked. I believe that this approach results in a concise unit test with some of the boilerplate code related to mocking removed.
Here's how a sample unit test looks with that approach:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(loader=AnnotationConfigContextLoader.class)
public class ExampleServiceIntegrationTest {
//our service under test, with mocked dependencies injected
#Autowired
ExampleService exampleService;
//we can autowire mocked beans if we need to used them in tests
#Autowired
DependencyBeanA dependencyBeanA;
#Test
public void testSomeMethod() {
...
exampleService.someMethod();
...
verify(dependencyBeanA, times(1)).someDependencyMethod();
}
/**
* Inner class configuration object for this test. Spring will read it thanks to
* #ContextConfiguration(loader=AnnotationConfigContextLoader.class) annotation on the test class.
*/
#Configuration
#Import(TestAppConfig.class) //TestAppConfig may contain some common integration testing configuration
#MockedBeans({DependencyBeanA.class, DependencyBeanB.class, AnotherDependency.class}) //Beans to be mocked
static class ContextConfiguration {
#Bean
public ExampleService exampleService() {
return new ExampleService(); //our service under test
}
}
}
To make this happen you need to define two simple helper classes - custom annotation (#MockedBeans) and a custom
ImportBeanDefinitionRegistrar implementation. #MockedBeans annotation definition needs to be annotated with #Import(CustomImportBeanDefinitionRegistrar.class) and the ImportBeanDefinitionRgistrar needs to add mocked beans definitions to the configuration in it's registerBeanDefinitions method.
If you like the approach you can find sample implementations on my blogpost.
Looking at Springockito pace of development and number of open issues, I would be little bit worried to introduce it into my test suite stack nowadays. Fact that last release was done before Spring 4 release brings up questions like "Is it possible to easily integrate it with Spring 4?". I don't know, because I didn't try it. I prefer pure Spring approach if I need to mock Spring bean in integration test.
There is an option to fake Spring bean with just plain Spring features. You need to use #Primary, #Profile and #ActiveProfiles annotations for it. I wrote a blog post on the topic.
I found a similar answer as teabot to create a MockFactory that provides the mocks. I used the following example to create the mock factory (since the link to narkisr are dead):
http://hg.randompage.org/java/src/407e78aa08a0/projects/bookmarking/backend/spring/src/test/java/org/randompage/bookmarking/backend/testUtils/MocksFactory.java
<bean id="someFacade" class="nl.package.test.MockFactory">
<property name="type" value="nl.package.someFacade"/>
</bean>
This also helps to prevent that Spring wants to resolve the injections from the mocked bean.
<bean id="mockDaoFactory" name="dao" class="com.package.test.MocksFactory">
<property name="type" value="com.package.Dao" />
</bean>
this ^ works perfectly well if declared first/early in the XML file. Mockito 1.9.0/Spring 3.0.5
I developed a solution based on the proposal of Kresimir Nesek. I added a new annotation #EnableMockedBean in order to make the code a bit cleaner and modular.
#EnableMockedBean
#SpringBootApplication
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes=MockedBeanTest.class)
public class MockedBeanTest {
#MockedBean
private HelloWorldService helloWorldService;
#Autowired
private MiddleComponent middleComponent;
#Test
public void helloWorldIsCalledOnlyOnce() {
middleComponent.getHelloMessage();
// THEN HelloWorldService is called only once
verify(helloWorldService, times(1)).getHelloMessage();
}
}
I have written a post explaining it.
I would suggest to migrate your project to Spring Boot 1.4. After that you can use new annotation #MockBean to fake your com.package.Dao
Today I found out that a spring context where I declared a before the Mockito beans, was failing to load.
After moving the AFTER the mocks, the app context was loaded successfully.
Take care :)
For the record, all my tests correctly work by just making the fixture lazy-initialized, e.g.:
<bean id="fixture"
class="it.tidalwave.northernwind.rca.embeddedserver.impl.DefaultEmbeddedServer"
lazy-init="true" /> <!-- To solve Mockito + Spring problems -->
<bean class="it.tidalwave.messagebus.aspect.spring.MessageBusAdapterFactory" />
<bean id="applicationMessageBus"
class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="it.tidalwave.messagebus.MessageBus" />
</bean>
<bean class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="javax.servlet.ServletContext" />
</bean>
I suppose the rationale is the one Mattias explains here (at the bottom of the post), that a workaround is changing the order the beans are declared - lazy initialization is "sort of" having the fixture declared at the end.
If you're using spring boot 2.2+, you can use #MockInBean as an alternative to #MockBean and keep your Spring context clean:
#SpringBootTest
public class MyServiceTest {
#MockInBean(MyService.class)
private ServiceToMock serviceToMock;
#Autowired
private MyService myService;
#Test
public void test() {
Mockito.when(serviceToMock.returnSomething()).thenReturn(new Object());
myService.doSomething();
}
}
disclaimer: I created this library to avoid Spring Context re-creation caused by #MockBean/#SpringBean that leads to slow build test phases (see Using #MockBean in tests forces reloading of Application Context or the problem with #MockBean)