jpa与spring整合

1：在Pom.xml中引入Spring框架

<projectxmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>

<groupId>com.dfrz</groupId>
<artifactId>Jpa_02</artifactId>
<version>0.0.1</version>
<packaging>jar</packaging>

<name>Jpa_02</name>
<url>http://maven.apache.org</url>

<properties>
<project.build.sourceEncoding>
UTF-8
</project.build.sourceEncoding>
<spring.version>4.2.6.RELEASE</spring.version>
</properties>

<dependencies>
<dependency>
<groupId>com.driver</groupId>
<artifactId>sqlserver</artifactId>
<version>2005</version>
</dependency>
<dependency>
<groupId>org.apache.openjpa</groupId>
<artifactId>openjpa-all</artifactId>
<version>2.2.0</version>
</dependency>
<!--引入Spring-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>${spring.version}</version>
</dependency>

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-instrument</artifactId>
<version>${spring.version}</version>
</dependency>
</dependencies>
</project>

2：Spring整合

Jpa:EntityManagerFactory---->EntityManager

Hibernate：SessionFactory---->Session

3:applicationContext.xml的配置

<?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:jdbc="http://www.springframework.org/schema/jdbc"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.1.xsd http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-3.1.xsd">

<context:annotation-config></context:annotation-config>
<context:component-scan
base-package="com.test"></context:component-scan>

<!-- 定义一个数据源 -->
<bean
name="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property
name="driverClassName"
value="com.microsoft.sqlserver.jdbc.SQLServerDriver">
</property>
<property
name="url"
value="jdbc:sqlserver://127.0.0.1:1433;databaseName=Java1503">
</property>
<property
name="username"
value="sa"></property>
<property
name="password"
value=""></property>
</bean>

<bean
name="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property
name="persistenceProviderClass"
value="org.apache.openjpa.persistence.PersistenceProviderImpl">
</property>
<property
name="packagesToScan"
value="com.jpa.entity">
</property>
<property
name="jpaProperties">
<props>
<prop
key="javax.persistence.jdbc.driver">
com.microsoft.sqlserver.jdbc.SQLServerDriver
</prop>
<prop
key="javax.persistence.jdbc.url">
jdbc:sqlserver://localhost:1433;DatabaseName=java1411;SelectMethod=cursor;
</prop>
<prop
key="javax.persistence.jdbc.user">sa</prop>
<prop
key="javax.persistence.jdbc.password"></prop>
<prop
key="openjpa.jdbc.SynchronizeMappings">
buildSchema(ForeignKeys=true)
</prop>
<prop
key="openjpa.Log">SQL=TRACE</prop>
<prop
key="openjpa.ConnectionFactoryProperties">
PrettyPrint=true,PrettyPrintLineLength=72
</prop>
<!-- 不启用jpa的类增强机制 -->
<prop
key="openjpa.ClassLoadEnhancement">false</prop>
<prop
key="openjpa.DynamicEnhancementAgent">false</prop>
<prop
key="openjpa.RuntimeUnenhancedClasses">
supported
</prop>

</props>
</property>
</bean>

<bean
name="transactionManager"
class="org.springframework.orm.jpa.JpaTransactionManager">
<property
name="entityManagerFactory"
ref="entityManagerFactory">
</property>
</bean>
<tx:annotation-driven
transaction-manager="transactionManager"
/>

</beans>

4：事务归jpa控制。

/**
* 事务归jpa控制。
*
* @author
ctd
*
*/
@Service
public
classTestMain_2 {
@Autowired
private
EntityManagerFactoryfactory;

public
EntityManagerFactorygetFactory() {
return
factory;
}

public
void setFactory(EntityManagerFactoryfactory) {
this.factory = factory;
}

/**
* jpa与Spring结合的过程中。如果事务归jpa控制。
*
* 那么在方法互相调用中。EntityManager由于是用factory.createEntityManager来创建的
*
* 类似(hibernate中session =SessionFactory.openSession)
*
* 因此不同的方法中，获取的manager不是同一个对象。那么事务就不是相同的事务。
*
* 无法保证方法互相调用中事务的统一。
*
* 要保证事务的统一：
*
* 1：使用Spring的声明式事务来统一控制。jpa中不使用事务。
*
* 2：不使用Spring的声明式事务来控制，那么在方法调用过程中，要进行事务对象的传递。
*
*
* @return
*/
public
boolean saveUser() {
EntityManagermanager = null;
EntityTransactiontx = null;
boolean flag =
false;
try {
manager= factory.createEntityManager();
System.out.println("manager_1 = "+ manager);
tx= manager.getTransaction();
tx.begin();

GroupBeangroupBean = newGroupBean();
groupBean.setGroupid(new Integer(1));
groupBean.setGroupname("java组");

GroupUseruser_1 = newGroupUser();
user_1.setUserid(new Integer(10));
user_1.setUsername("用户1");
user_1.setGroupBean(groupBean);

GroupUseruser_2 = newGroupUser();
user_2.setUserid(new Integer(20));
user_2.setUsername("用户2");
user_2.setGroupBean(groupBean);

manager.persist(groupBean);
manager.persist(user_1);
int i = 10/0;
manager.persist(user_2);

tx.commit();
}catch(Exception e) {
e.printStackTrace();
tx.rollback();
}
return flag;
}

public
static void main(String[] args) {
ApplicationContextcontext = newClassPathXmlApplicationContext(
"applicationContext.xml");

TestMain_2testMain_2 = (TestMain_2) context.getBean("testMain_2");

testMain_2.saveUser();
}

}

5：事务归Spring控制。

5.1：在配置文件中打开声明式事务的注解。

<beanname="transactionManager"
class="org.springframework.orm.jpa.JpaTransactionManager">
<propertyname="entityManagerFactory"
ref="entityManagerFactory">
</property>
</bean>
<tx:annotation-driventransaction-manager="transactionManager" />

5.2：在代码中控制事务:

/**
* 事务归Spring声明式事务控制。
*
* @author
ctd
*
*/
@Service
@Transactional
public
classTestMain_3 {
@PersistenceContext
/**
* @PersistenceContext，将创建的EntityManager放到上下文对象中。
*
* 达到EntityManager在方法中共享效果 ==类似于Hibernate中的getCurrentSession的操作。
*/
private
EntityManager manager;

public
EntityManagergetEntityManager() {
return
manager;
}

public
void setEntityManager(EntityManagermanager) {
this.manager = manager;
}

@Autowired
private UserDAO
userdao;

/**
* 方法要受到声明式事务的管理：必须声明为public类型。
*
* @return
*/
public
boolean saveGroup() {
boolean flag =
false;
try {
System.out.println("saveGroup--->manager = " +
manager);

GroupBeangroupBean = newGroupBean();
groupBean.setGroupid(new Integer(1));
groupBean.setGroupname("java组");
manager.persist(groupBean);

// 测试：相同类中相同的方法，事务是否一致性。
// this.saveUser();

// 测试：不同类中方法的调用，事务是否一致性
userdao.saveUser();
}catch(Exception e) {
e.printStackTrace();
throw
new RuntimeException(e);
}
return flag;
}

public
void saveUser() {
System.out.println("saveUser--->manager = " +
manager);
GroupBeangroupBean = (GroupBean) manager.find(GroupBean.class,
new Integer(1));
GroupUseruser_1 = newGroupUser();
user_1.setUserid(new Integer(10));
user_1.setUsername("用户1");
user_1.setGroupBean(groupBean);

GroupUseruser_2 = newGroupUser();
user_2.setUserid(new Integer(20));
user_2.setUsername("用户2");
user_2.setGroupBean(groupBean);

manager.persist(user_1);
int i = 10 / 0;

manager.persist(user_2);
}

public
static void main(String[] args) {
ApplicationContextcontext = newClassPathXmlApplicationContext(
"applicationContext.xml");

TestMain_3testMain_3 = (TestMain_3) context.getBean("testMain_3");

testMain_3.saveGroup();
}

}