@PersistenceContext will make Spring inject an EntityManager into the service when it is instantiated. The @PersistenceContext annotation can be placed on the field, or on the setter method. If the class is annotated as @Transactional, Spring will make sure that its methods run inside a transaction.
JPA configuration
- Create a folder named "META-INF" under the "src" folder.
- Create a file named "persistence.xml" under the "META-INF" folder and set its content to:
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
version="1.0">
<persistence-unit name="punit">
</persistence-unit>
</persistence>
JPA configuration can be set on this file. On this example it will be empty because the datasource configuration will be on the Spring configuration file.
Spring
- Update the content of web.xml under /WebContent/WEB-INF/web.xml to:
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="person" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>person</display-name>
<filter>
<filter-name>struts2</filter-name>
<filter-class>
org.apache.struts2.dispatcher.FilterDispatcher
</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
</web-app>
This will make the container redirect all requests to Struts "FilterDispatcher" class. "index.jsp" is set as the home page, and Springs "ContextLoaderListener" is configured as a listener.
- Create a file named "applicationContext.xml" under /WebContent/WEB-INF, and set its content to:
<?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"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
<bean
class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />
<bean id="personService" class="quickstart.service.PersonServiceImpl" />
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean
class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="database" value="MYSQL" />
<property name="showSql" value="true" />
</bean>
</property>
</bean>
<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost/quickstart" />
<property name="username" value="root" />
<property name="password" value="root" />
</bean>
<bean id="transactionManager"
class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
<bean id="personAction" scope="prototype"
class="quickstart.action.PersonAction">
<constructor-arg ref="personService" />
</bean>
</beans>
