Spring @Autowired实例为null

Question

我目前正在尝试设置REST Service Spring应用程序，并实现了一个模型及其控制器+ dao和服务以与MySQL数据库进行通信。

现在，我的AccountController是带有注释的@RestController的bean，而AccountService是@Component Bean。 AccountService拥有一个@ Autowire'd AccountDao成员，而AccountController拥有一个@ Autowire'd AccountService成员。

dataAccess.xml如下：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
      destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://localhost:3306/fashion" />
        <property name="username" value="root" />
        <property name="password" value="fashion" />
    </bean>

    <bean id="sessionFactory"
      class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="mappingResources">
            <list>
                <value>de/appsiting/fashion/model/Account.hbm.xml</value>
           </list>
        </property>
        <property name="hibernateProperties">
           <props>
                <prop key="hibernate.dialect">
                org.hibernate.dialect.MySQL5Dialect
                </prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">create</prop>
           </props>
        </property>
    </bean>

    <bean id="jdbcExceptionTranslator" class="org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator">
       <property name="dataSource">
            <ref bean="dataSource" />
       </property>
    </bean>

    <bean id="accountDao" class="de.appsiting.fashion.persistence.AccountDao" />
</beans>

但是， Account.hbm.xml被涂成红色，表明应用程序找不到它。 因此，我的第一个问题是，为什么不从resources文件夹中根目录找到.hbm.xml？

如下所示填充serviceBeans.xml ：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:task="http://www.springframework.org/schema/task"
       xsi:schemaLocation="
    http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.0.xsd
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">

    <task:annotation-driven/>

    <bean id="hibernateStringEncryptor" class="org.jasypt.hibernate4.encryptor.HibernatePBEStringEncryptor">
        <property name="registeredName">
            <value>strongHibernateStringEncryptor</value>
        </property>
        <property name="algorithm">
            <value>PBEWithMD5AndTripleDES</value>
        </property>
        <property name="password">
            <value>jasypt</value>
        </property>
    </bean>

    <bean id="accountService" class="de.appsiting.fashion.service.AccountService">
        <property name="accountDao" ref="accountDao" />
    </bean>

    <!-- *** TX LAYER -->
    <bean id="txManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory" />
    </bean>
    <tx:advice id="tx.advice" transaction-manager="txManager">
        <tx:attributes>
            <tx:method name="*" propagation="REQUIRED" read-only="false" />
            <tx:method name="get*" propagation="REQUIRED" read-only="false" />
        </tx:attributes>
    </tx:advice>

    <!-- *** AOP -->
    <aop:config>
        <aop:pointcut id="accountServiceMethods" expression="execution(* de.appsiting.fashion.service.AccountService.*(..))" />

        <aop:advisor advice-ref="tx.advice" pointcut-ref="accountServiceMethods" />
    </aop:config>
</beans>

现在，当运行我的AccountTest时 ，accountService为null，因此测试失败：

import de.appsiting.fashion.service.AccountService;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.junit.Test;


/**
 * Created by mak on 4/22/16.
 */
public class AccountTest {
    private static Logger log = Logger.getLogger(AccountTest.class);

    @Autowired
    private AccountService accountService;

    @Test
    public void testCreateAccount() throws Exception {
        Account account = new Account();
        account.setUsername("testfashion");
        account.setPassword("testfashion");
        account.setEmail("test@appsiting");

        accountService.addAccount(account);
    }
}

为什么会这样？

Answer 1

您应该使用SpringJUnit4ClassRunner来初始化应用程序上下文，以便依赖项注入能够运行。

另一个选择是使用Mockito ，它在恕我直言中避免了很多麻烦，并且您获得了使用模拟的好处。

Answer 2

您在测试中缺少两种配置。

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations={"Location of xml files that you need to load for tests to run"})
public class AccountTest {

}

以上配置将为您的测试加载上下文。 或者，您可以在设置方法中加载测试的应用程序上下文，然后使用该上下文获取帐户服务。

Answer 3

我认为您应该在serviceBeans.xml中添加以下内容，

<bean id="accountDao" class="de.appsiting.fashion.persistence.AccountDao" />

并删除AccountService类中的@Autowired AccountDao批注，并添加一个AccountDao的设置器。