我有一个奇怪的问题。我正在使用 applicatioContext bean 使用 PersistenceContext 注入实体管理器。但问题是，当我运行测试用例时，实体管理器已成功注入，但在运行 Web 应用程序时会抛出 NullPointerException
这是我要注入 entityManager 的 abstractRepository
package com.ajit.retail.repository;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;
public class AbstractRepository {
@PersistenceContext(type = PersistenceContextType.EXTENDED)
EntityManager entityManager;
}
这是我使用实体管理器的存储库
package com.ajit.retail.repository;
import com.ajit.retail.exception.InvalidIdException;
import com.ajit.retail.model.Buyer;
import org.springframework.stereotype.Repository;
import javax.persistence.NoResultException;
@Repository
public class BuyerRepo extends AbstractRepository {
public Buyer getBuyer(String buyerName) throws InvalidIdException {
javax.persistence.Query buyerId = entityManager.createNativeQuery("select b.buyer_id from buyer b where b.name = :name").setParameter("name", buyerName);
Integer id;
try {
id = (Integer) buyerId.getSingleResult();
} catch (NoResultException e) {
return null;
}
return getBuyer(id);
}
public Buyer getBuyer(long buyerId) throws InvalidIdException {
Buyer buyer = entityManager.find(Buyer.class, buyerId); **====> NULL**
if (buyer == null) throw new InvalidIdException("Invalid Article ID");
return buyer;
}
}
这是我的控制器，它正在调用存储库方法
package com.ajit.retail.web;
import com.sun.jersey.spi.inject.Inject;
import com.ajit.retail.exception.InvalidIdException;
import com.ajit.retail.model.Buyer;
import com.ajit.retail.repository.*;
import org.springframework.stereotype.Component;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
@Path("/buyer")
@Component
public class BuyerController {
@Inject
private BuyerRepo buyerRepo;
@GET
@Produces(MediaType.APPLICATION_JSON)
public Buyer searchFields() throws InvalidIdException {
String buyerId = "51";
Buyer buyer;
try {
buyer = buyerRepo.getBuyer(Long.parseLong(buyerId));
} catch (NumberFormatException e) {
buyer = buyerRepo.getBuyer(buyerId);
}
return buyer;
}
}
这些是通过的单元测试
包 com.ajit.retail.repository；
import com.ajit.retail.exception.InvalidIdException;
import org.hamcrest.core.IsEqual;
import org.junit.Before;
import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;
import static org.junit.Assert.assertThat;
public class BuyerRepoTest extends BaseRepository {
@Autowired
private BuyerRepo buyerRepo;
@Test
public void shouldGiveNameOfGivenBuyerId() throws InvalidIdException {
assertThat(buyerRepo.getBuyer(2).getName(), IsEqual.equalTo("SupervisorDLS"));
}
@Test(expected = InvalidIdException.class)
public void shouldThrowExceptionForInvalidBuyerId() throws InvalidIdException {
buyerRepo.getBuyer(-10);
}
}
这是基础存储库
package com.ajit.retail.repository;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.AbstractTransactionalJUnit4SpringContextTests;
@ContextConfiguration(locations = {"classpath:applicationContext.xml"})
public class BaseRepository extends AbstractTransactionalJUnit4SpringContextTests {
}
这是 applicationContext.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:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx" xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
<context:annotation-config/>
<context:component-scan base-package="com.ajit.retail"/>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="org.postgresql.Driver"/>
<property name="url" value="jdbc:postgresql://localhost/retail"/>
<property name="username" value="retail_user"/>
<property name="password" value="password"/>
</bean>
<bean id="entityManager" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="packagesToScan" value="com.ajit.retail"/>
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="showSql" value="true"/>
<property name="databasePlatform" value="org.hibernate.dialect.PostgreSQLDialect"/>
</bean>
</property>
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManager"/>
</bean>
<tx:annotation-driven transaction-manager="transactionManager"/>
</beans>
请帮忙！