在 CDI 单元中注入 @PersistenceContext

Question

这是单元测试代码。当我们运行单元测试代码（SampleServiceTest2）时； AbstractDao 中注入的 EntityManager 始终为空！我们如何在单元测试期间注入 em。

*** SampleServiceTest2.java

import javax.inject.Inject;

import org.jglue.cdiunit.CdiRunner;
import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(CdiRunner.class)
public class SampleServiceTest2 {

    @Inject SampleService greeter; 

    @Test
    public void testGreeter() throws Exception { 
        System.out.println("before2");
        greeter.addSampleData(new SampleDataDto(), new KullaniciDto()); 
        System.out.println("after2");
    } 
}

*** SampleService.java

import javax.ejb.Stateless;
import javax.inject.Inject;
....

@Stateless
@SecuredBean
public class SampleService {

    @Inject 
    SampleLogic sampleLogic;

    @Yetki(tag="perm_add_sample_data")
    public void addSampleData(SampleDataDto data, KullaniciDto aktifKullaniciDto){
        SampleDataHelper sampleDataHelper = new SampleDataHelper();

        SampleData sampleData = sampleDataHelper.getEntity(data);
        KullaniciHelper kullaniciHelper = new KullaniciHelper();

        Kullanici kullanici = kullaniciHelper.getEntity(aktifKullaniciDto);
        sampleLogic.addData(sampleData, kullanici);
    }

}

**** SampleLogic.java

import javax.inject.Inject;

....

public class SampleLogic {
    @Inject 
    SampleDataDao sampleDataDao;

    public void addData(SampleData data, Kullanici kullanici) {
        addData1(data,kullanici);   
        System.out.println("SampleLogic : addData() called!");
    }

    public void addData1(SampleData data, Kullanici kullanici) {
        sampleDataDao.create(data, kullanici);
    }
}

**** SampleDataDao.java

public class SampleDataDao extends AbstractDao<SampleData> {
    private static final long serialVersionUID = 1L;
}

**** AbstractDao.java

public abstract class AbstractDao<T extends BaseEntity> implements Serializable {

    private static final long serialVersionUID = 1L;

    @PersistenceContext(unitName="meopdb")
    private EntityManager em;

    protected EntityManager getEm() {
        return em;
    }

    @SuppressWarnings("rawtypes")
    private Class entityClass;


    @SuppressWarnings("rawtypes")
    private Class getEntityClass() {
        if (entityClass == null) {
            entityClass = (Class) ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
        }
        return entityClass;
    }

    public T create(T t, Kullanici kullanici) {
        if (t.getId() != null) {
            throw new IllegalStateException("Create Operation: Oid should be null");
        }
        t.setId(getSeqNextValue(t));
        t.setEklemeZamani(new Timestamp(Calendar.getInstance().getTimeInMillis()));
        t.setEkleyenKullaniciId(kullanici.getId());

        t.setDurumId(EnumDurum.AKTIF.getValue());

        t = em.merge(t);
        em.flush();
        return t;
    }
}

Answer 1

如果您使用 CDIUnit 进行测试，您得到的唯一结果就是 CDI 注入，而不是 Java EE 的全部功能。使用@PersistenceContext 将 entityManager 注入AbstractDAO 不是独立 CDI 的一部分，仅当应用程序在 Java EE 应用程序服务器中运行时才受支持。

解决方法是使用CDI机制注入EntityManager，创建producer。然后可以在单元测试中切换生产者以提供测试 entityManager。但是，在独立的单元测试中设置 JPA 并不是那么简单，因为您需要直接在 persistence.xml 文件中指定连接属性。此外，不要忘记将 JPA 实现（hibernate、eclipselink）的依赖项添加到您的测试依赖项中。

但是，如果您不想调整应用程序的代码，或者您在测试中需要的不仅仅是 CDI，您应该查看Arquillian Java EE test framework。

以下是 CDIUnit 的示例：

public abstract class AbstractDao<T extends BaseEntity> implements Serializable {
...
    @Inject
    @Named("meopdb")
    private EntityManager em;
...
}

// producer in application - just a wraper over `@PersisteneContext`
public class EntityManagerProducer {
    @Produces
    @PersistenceContext(unitName="meopdb")
    @Named("meopdb")
    private EntityManager em;
}

/* producer in your test sources - it creates entityManager via API calls instead of injecting via `@PersistenceContext`. Also, a different persistence unit is used so that it does not clash with main persistence unit, which requires datasource from app server 
*/
public TestEntityManagerProducer {
    @Produces
    @ProducesAlternative // CDIUnit annotation to turn this on as an alternative automatically
    @Named("meopdb")
    public EntityManager getEm() {
        return Persistence
                .createEntityManagerFactory("meopdb-test")
                .createEntityManager();
    }

}

这还不够。您需要使用名为“meopdb-test”的测试持久性单元在测试资源中创建一个新的persistence.xml。对于这个单元，您需要指定RESOURCE_LOCAL transaction-type，并指定连接信息。最后一件事不要忘记 - 您需要在 persistence.xml 或外部 orm 文件中列出所有实体。这是因为您的测试在应用程序服务器之外运行。在应用服务器内部，JPA 可以自动查找实体。

Answer 2

正如@OndroMih 所说，在 CDI-Unit 中，您唯一得到的就是 CDI 注入。所以你必须作弊。

您可以使用扩展为所有@PersistenceContext 注入添加javax.inject.Inject 注释

import java.util.Set;

import javax.enterprise.event.Observes;
import javax.enterprise.inject.spi.*;
import javax.inject.Inject;
import javax.persistence.PersistenceContext;

import org.apache.deltaspike.core.util.metadata.AnnotationInstanceProvider;
import org.apache.deltaspike.core.util.metadata.builder.AnnotatedTypeBuilder;



public class AddInjectToPersistenceContextInjectionsCdiExtension implements Extension {
    <T> void processAnnotatedType(@Observes ProcessAnnotatedType<T> pat) {
       Set<AnnotatedField<? super T>> fields = pat.getAnnotatedType().getFields();
       for (AnnotatedField<? super T> field : fields) {
          if (shouldInjectionAnnotationBeAddedToField(field)) {
             AnnotatedType<T> at = pat.getAnnotatedType();
             AnnotatedTypeBuilder<T> builder = new AnnotatedTypeBuilder<T>().readFromType(at);
             Inject injectAnnotation = AnnotationInstanceProvider.of(Inject.class);
             builder.addToField(field, injectAnnotation);
             pat.setAnnotatedType(builder.create());
          }
       }
    }

    private <X> boolean shouldInjectionAnnotationBeAddedToField(AnnotatedField<? super X> field) {
       return !field.isAnnotationPresent(Inject.class) && 
          field.isAnnotationPresent(PersistenceContext.class);
    }
}

并在测试类中生成合适的EntityManager

@RunWith(CdiRunner.class)
@AdditionalClasses(AddInjectToPersistenceContextInjectionsCdiExtension.class)
public class SampleServiceTest2 {

    @Inject SampleService greeter;

    EntityManagerFactory emf;

    @PostConstruct
    void init() {
        emf = Persistence.createEntityManagerFactory("integration");
    }

    @Produces
    EntityManager createEntityManager() {
        return emf.createEntityManager();
    }

    @Test
    public void testGreeter() throws Exception  {

    }
}

它并不完全等同于 Java EE 容器的功能，但它通常足够接近。