This post describes how to implement JUnit tests for a Spring Web Application's Services and DAO. It is built on top of the
Spring MVC-Service-DAO-Persistence Architecture Example. This example is available from
Github in the
Spring-Web-JPA-Testing directory.
Reminder
- Test Fixture - The fixed state used as a baseline for running tests.
- Unit test - These tests verify that pieces of code
(components) perform some functionalities as expected. In a Java
environment, these are typically implemented at the class level.
- Integration test - Integration testing is any type of test
checking that a set of interacting components perform expected
functionalities together correctly.
Configuration
We need a JPA Hibernate configuration for in-memory testing:
@Configuration
@EnableTransactionManagement
public class JpaTestConfig {
@Bean
public LocalContainerEntityManagerFactoryBean entityManagerFactoryBean(){
LocalContainerEntityManagerFactoryBean lcemfb
= new LocalContainerEntityManagerFactoryBean();
lcemfb.setDataSource(this.dataSource());
lcemfb.setPackagesToScan(new String[] {"com.jverstry"});
lcemfb.setPersistenceUnitName("MyTestPU");
HibernateJpaVendorAdapter va = new HibernateJpaVendorAdapter();
lcemfb.setJpaVendorAdapter(va);
Properties ps = new Properties();
ps.put("hibernate.dialect", "org.hibernate.dialect.HSQLDialect");
ps.put("hibernate.hbm2ddl.auto", "create");
lcemfb.setJpaProperties(ps);
lcemfb.afterPropertiesSet();
return lcemfb;
}
@Bean
public DataSource dataSource(){
DriverManagerDataSource ds = new DriverManagerDataSource();
ds.setDriverClassName("org.hsqldb.jdbcDriver");
ds.setUrl("jdbc:hsqldb:mem:testdb");
ds.setUsername("sa");
ds.setPassword("");
return ds;
}
@Bean
public PlatformTransactionManager transactionManager(){
JpaTransactionManager tm = new JpaTransactionManager();
tm.setEntityManagerFactory(
this.entityManagerFactoryBean().getObject() );
return tm;
}
@Bean
public PersistenceExceptionTranslationPostProcessor exceptionTranslation(){
return new PersistenceExceptionTranslationPostProcessor();
}
}
We need to exclude the production configuration from package scanning (no
"com.jverstry" scanning):
@Configuration
@ComponentScan(basePackages = {
"com.jverstry.Controller",
"com.jverstry.DAO",
"com.jverstry.Item",
"com.jverstry.Service"
})
public class TestConfig {
@Bean
public MyService getMyService() {
return new MyServiceImpl();
}
}
Spring Testing Tools
- @RunWith - This is a JUnit annotation allowing one to run a test with a different runner than the one provided by JUnit.
- SpringJUnit4ClassRunner - This is a JUnit test runner for Spring applications. Typically, test classes are annoted with @RunWith(SpringJUnit4ClassRunner.class).
- @ContextConfiguration - This annotation can be used to specify how to load an applicationContext in Spring test class. This can be configured via XML files or Java configuration objects.
Service Testing
The following class tests the
createAndRetrieve() method of our injected
MyService implementation:
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes={ JpaTestConfig.class, TestConfig.class })
public class MyServiceImplTest {
@Autowired
private MyService myService;
@Test
public void testCreateAndRetrieve() {
MilliTimeItem retr = myService.createAndRetrieve();
assertNotNull(retr);
}
}
DAO Testing
The following class tests our DAO implementation. Our implementation is injected with an EntityManager created from our test configuration class defined above.
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes={ JpaTestConfig.class, TestConfig.class })
public class MyPersistenceDAOTest {
@Autowired
private MyPersistenceDAO myDAO;
@Test
public void testCreateMilliTimeItem() {
// This operation should not throw an Exception
long id = myDAO.createMilliTimeItem();
}
@Test
public void testGetMilliTimeItem() {
long id = myDAO.createMilliTimeItem();
MilliTimeItem retr = myDAO.getMilliTimeItem(id);
assertNotNull(retr);
assertEquals(id,retr.getID());
}
}
Caveat
When starting to write JUnit tests for Spring, one can come across the following error messages:
Java.lang.ClassFormatError:
Absent Code attribute in method that is not native or abstract in class file javax/validation/Validation
The above is often caused by the following maven dependency:
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>6.0</version>
<type>jar</type>
</dependency>
It should be replaced with:
<dependency>
<groupId>org.apache.geronimo.specs</groupId>
<artifactId>geronimo-jpa_2.0_spec</artifactId>
<version>1.1</version>
<scope>provided</scope>
</dependency>
Another error message is:
javax.validation.ValidationException: Unable to find a default provider
This is solved by adding the following maven dependency:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>4.3.0.Final</version>
</dependency>
For Spring MVC Controller JUnit testing, see
here • More Spring related posts
here.
