@Autowired没有类型的限定bean-bean扩展抽象类

Question

在package-data.dao中有一个bean

@Component("questionDao")
@Transactional
public class QuestionDao extends AbstractDao<Question, Long>{

}

@Autowired
@Qualifier(value="questionDao")
private QuestionDao questionDao;

@Component("questionDao")
@Transactional
public class QuestionDao extends AbstractDao<Question, Long>{
    public void doSomething(){
    }
}

public class AbstractDao<T, ID extends Serializable> implements Dao<T, ID> {

    @Autowired
    protected SessionFactory sessionFactory;

    private Class<T> persistentClass;
    private Transaction transaction;

    @SuppressWarnings("unchecked")
    public AbstractDao() {
        this.persistentClass = (Class<T>) ((ParameterizedType) getClass().getGenericSuperclass())
                .getActualTypeArguments()[0];
    }

    protected Session getSession() {
        return sessionFactory.getCurrentSession();
    }

    public Class<T> getPersistentClass() {
        return persistentClass;
    }

    @SuppressWarnings("unchecked")
    @Override
    public T findById(ID id) {
        transaction = getSession().beginTransaction();

        T object = (T) getSession().load(this.getPersistentClass(), id);

        transaction.commit();

        return object;
    }

    @Override
    public List<T> findAll() {
        transaction = getSession().beginTransaction();

        List<T> list = this.findByCriteria();

        transaction.commit();

        return list;
    }

    @SuppressWarnings("unchecked")
    protected List<T> findByCriteria(Criterion... criterion) {
        Criteria crit = this.getSession().createCriteria(this.getPersistentClass());

        for (Criterion c : criterion) {
            crit.add(c);
        }
        return (List<T>) crit.list();
    }

    @Override
    public T create(T entity) {
        transaction = getSession().beginTransaction();

        getSession().saveOrUpdate(entity);

        transaction.commit();

        return entity;
    }

    @Override
    public void delete(T entity) {
        transaction = getSession().beginTransaction();

        getSession().delete(entity);

        transaction.commit();
    }

    @Override
    public void deleteTable() {
        transaction = getSession().beginTransaction();

        String deleteTable = new String ("delete " + this.getPersistentClass().getName());

        Query query = getSession().createQuery(deleteTable);
        query.executeUpdate();

        transaction.commit();
    }

}

<bean id="sessionFactory"
            class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
            <property name="dataSource" ref="dataSource"></property>
            <property name="hibernateProperties">
                <props>
                    <prop key="hibernate.dialect">org.hibernate.dialect.PostgreSQL9Dialect</prop>
                    <prop key="hibernate.show_sql">true</prop>
                </props>
            </property>
            <property name="packagesToScan">
                <list>
                    <value>sk.uniza.fri.cuka.data.dao</value>
                    <value>sk.uniza.fri.cuka.data.entity</value>
                </list>
            </property>
        </bean>

完整StackTrace：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sk.uniza.fri.cuka.test.tests.AnswerDaoTest': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private sk.uniza.fri.cuka.data.dao.QuestionDao sk.uniza.fri.cuka.test.tests.AnswerDaoTest.questionDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [sk.uniza.fri.cuka.data.dao.QuestionDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=questionDao)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:385)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:212)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:200)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:259)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:261)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:219)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:83)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:68)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:163)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private sk.uniza.fri.cuka.data.dao.QuestionDao sk.uniza.fri.cuka.test.tests.AnswerDaoTest.questionDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [sk.uniza.fri.cuka.data.dao.QuestionDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=questionDao)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
    ... 26 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [sk.uniza.fri.cuka.data.dao.QuestionDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=questionDao)}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1301)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1047)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
    ... 28 more

编辑：问题解决了：我只是删除了“@transactional”，它可以工作了。我还重构了一点我的问题，这样它就实现了Peter Jurkovic建议的接口。

Answer 1

Dao接口有一个问题。从您的questiondao中提取接口，它应该可以工作。

public interface QuestionDao extends Dao<Question, Long>{
    public void doSomething();
}

创建QuestionDaoImpl

@Transactional
@Repository("questionDao")
public class QuestionDaoImpl extends AbstractDao<Question, Long> implements QuestionDao{
    public void doSomething(){
    }
}