问题
I need to implement Spring's @Transactional annotation but I'm not being able to do so.
I had tried a lot of methods in the past 3 weeks but none of them worked.
I'm also need to use EntityManager. To test if Spring's was working, I tried to inject the EntityManager using @PersistenceContext (I also tried using @PersistenceUnit and/with EntityManagerFactory) but always I got nullPointerException.
@PersistenceContext(unitName = "sistema")
protected EntityManager entityManager;
Basically I need to know how to make spring's annotations to work and how to implement a Transaction manager using those technologies:
persitence.xml
<?xml version="1.0" encoding="UTF-8"?>
<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_2_0.xsd"
version="2.0">
<persistence-unit name="sistema" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.sis.vo.Person</class>
<properties>
<property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver" />
<property name="hibernate.connection.autocommit" value="false" />
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/>
<property name="hibernate.enable_lazy_load_no_trans" value="false"/>
<property name="hibernate.show_sql" value="false" />
<property name="hibernate.format_sql" value="false"/>
<!-- do I need those? -->
<property name="hibernate.connection.url" value="jdbc:mysql://localhost/myDatabase?autoReconnect=true&useSSL=false" />
<property name="hibernate.connection.username" value="myUser" />
<property name="hibernate.connection.password" value="myPass" />
</properties>
</persistence-unit>
</persistence>
spring.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:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:jee="http://www.springframework.org/schema/jee"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.3.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
http://www.springframework.org/schema/jee
http://www.springframework.org/schema/jee/spring-jee-4.3.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">
<context:annotation-config />
<mvc:annotation-driven />
<bean id="hikariConfig" class="com.zaxxer.hikari.HikariConfig">
<property name="poolName" value="sisHikariCP" />
<property name="connectionTestQuery" value="SELECT 1" />
<property name="dataSourceClassName" value="com.mysql.jdbc.jdbc2.optional.MysqlDataSource" />
<property name="minimumIdle" value="3" />
<property name="maximumPoolSize" value="100" />
<property name="idleTimeout" value="740000" />
<property name="maxLifetime" value="1740000" />
<property name="leakDetectionThreshold" value="30000" />
<property name="dataSourceProperties">
<props>
<prop key="url">jdbc:mysql://localhost/myDatabase?autoReconnect=true&useSSL=false</prop>
<prop key="user">myUser</prop>
<prop key="password">myPass</prop>
<prop key="prepStmtCacheSize">350</prop>
<prop key="prepStmtCacheSqlLimit">2048</prop>
<prop key="cachePrepStmts">true</prop>
<prop key="useServerPrepStmts">true</prop>
<prop key="useLocalSessionState">true</prop>
<prop key="useLocalTransactionState">true</prop>
<prop key="rewriteBatchedStatements">true</prop>
<prop key="cacheResultSetMetadata">true</prop>
<prop key="cacheResultSetMetadata">true</prop>
<prop key="cacheServerConfiguration">true</prop>
<prop key="elideSetAutoCommits">true</prop>
<prop key="maintainTimeStats">false</prop>
</props>
</property>
</bean>
<bean id="dataSource" class="com.zaxxer.hikari.HikariDataSource" destroy-method="close">
<constructor-arg ref="hikariConfig" />
</bean>
<bean id="myJpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter" ref="myJpaVendorAdapter" />
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
</beans>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>sis</display-name>
<context-param>
<param-name>javax.faces.INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL</param-name>
<param-value>true</param-value>
</context-param>
<welcome-file-list>
<welcome-file>index.jsf</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>Faces Servlet</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.jsf</url-pattern>
</servlet-mapping>
<!-- SPRING -->
<servlet>
<servlet-name>Spring Servlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/spring.xml
</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
</web-app>
DAO
@Repository
public class GenericListDAO<E> {
@PersistenceContext(unitName = "sistema")
protected EntityManager entityManager;
public EntityManager getEntityManager() {
return entityManager;
}
public GenericListDAO() {
}
//rest of the code (persist, find, etc)
}
Versions:
- Spring Version: 4.3.12
- Hibernate Version: 5.1.10.Final
- HikariCP Version: 2.7.3
- JDK Version: 1.8.0_121
- Tomcat version: 8.5.23
Thank you!
回答1:
This is what i use to configure my transaction manager
<bean id="myDatasource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
<bean id="myJpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="myDatasource" />
<property name="jpaVendorAdapter" ref="myJpaVendorAdapter" />
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
entityManagerFactory
bean will use your persistence.xml
from classpath to create the persistance unit.
update get your persistence context like this
@PersistenceContext(unitName="sistema")
protected EntityManager em;
also make sure the class that is using the persistence context is annotated with @Repository
update
can you add this to your web.xml
<!-- The definition of the Root Spring Container shared by all Servlets
and Filters -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
classpath:/WEB-INF/spring-root-context.xml
</param-value>
</context-param>
<!-- Creates the Spring Container shared by all Servlets and Filters -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
now create a new file spring-root-context.xml
next to spring.xml
and move all the DB and transaction related stuff to spring-root-context.xml
.
So spring.xml
will be your servlet context and spring-root-context.xml
will be your root context.
anything related to controllers will go to spring.xml
all other beans will go to spring-root-context.xml
also add <context:component-scan base-package="package.for.genericdao" />
to both spring.xml
and spring-root-context.xml
and replace package.for.genericdao with your base package name.
来源:https://stackoverflow.com/questions/47624373/how-to-implement-springs-transactional-annotation-using-hibernate-hikaricp-an