Spring MVC事務配置
要了解事務配置的所有方法,請看一下《Spring事務配置的5種方法》
本文介紹兩種配置方法:
1、 XML,使用tx標籤配置攔截器實現事務
2、 Annotation方式
以下所使用環境爲Spring4.0.3、Hibernate4.3.5
一、 XML,使用tx標籤配置攔截器實現事務
Entity類User.java,持久化類,對應數據庫表user
package com.lei.demo.entity;
import javax.persistence.*;
@Entity(name="users")
public class Users {
public Users(){
super();
}
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
@Column(name="id")
private Integer id;
@Column(name="user_name",length=32)
private String user_name;
@Column(name="age")
private Integer age;
@Column(name="nice_name",length=32)
private String nice_name;
//屬性實現......
}
UserDAO.javar,表user的一些操作,其中屬性sessionFactory應該由Spring注入,如下:
package com.lei.demo.dao;
import java.util.List;
import javax.annotation.Resource;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.stereotype.Repository;
import com.lei.demo.entity.Users;
public class UsersDAO {
private SessionFactory sessionFactory;
public void setSessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
}
public SessionFactory getSessionFactory() {
return sessionFactory;
}
public List<Users> getAllUser(){
String hsql="from users";
Session session = sessionFactory.getCurrentSession();
Query query = session.createQuery(hsql);
return query.list();
}
}
UserService.java,業務實現類,如下
package com.lei.demo.service;
import javax.annotation.Resource;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import com.lei.demo.dao.*;
public class UserService {
private UsersDAO userDao;
public int userCount(){
return userDao.getAllUser().size();
}
public UsersDAO getUserDao() {
return userDao;
}
public void setUserDao(UsersDAO userDao) {
this.userDao = userDao;
}
}
首先看一下xml配置,spring-hibernate.xml如下:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
">
<!-- Hibernate4 -->
<!-- 加載資源文件 其中包含變量信息,必須在Spring配置文件的最前面加載,即第一個加載-->
<context:property-placeholder location="classpath:persistence-mysql.properties" />
<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan">
<list>
<!-- 可以加多個包 -->
<value>com.lei.demo.entity</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
<prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
<!-- <prop key="hibernate.current_session_context_class">thread</prop> -->
</props>
</property>
</bean>
<!-- 數據庫映射 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}" />
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.user}" />
<property name="password" value="${jdbc.pass}" />
</bean>
<!-- 配置Hibernate事務管理器 -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<!-- 配置事務異常封裝 -->
<bean id="persistenceExceptionTranslationPostProcessor"
class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />
<!-- 聲明式容器事務管理 ,transaction-manager指定事務管理器爲transactionManager -->
<tx:advice id="txAdvice" transaction-manager="transactionManager">
<tx:attributes>
<tx:method name="add*" propagation="REQUIRED" />
<tx:method name="get*" propagation="REQUIRED" />
<tx:method name="*" read-only="true" />
</tx:attributes>
</tx:advice>
<aop:config expose-proxy="true">
<!-- 只對業務邏輯層實施事務 -->
<aop:pointcut id="txPointcut" expression="execution(* com.lei.demo.service..*.*(..))" />
<!-- Advisor定義,切入點和通知分別爲txPointcut、txAdvice -->
<aop:advisor pointcut-ref="txPointcut" advice-ref="txAdvice"/>
</aop:config>
</beans>
其中主要配置中是tx:advice和aop:config兩個配置節,以Spring AOP的方式實現事務管理。
tx:advice配置了事務的管理者是transactionManager,同時tx:method也規定了如果方法名匹配“add*”和“get*”方法時使用事務,propagation是設定事務的傳播級別。除了“add*”和“get*”方法,其他的方法的事務是隻讀的(典型地,對於只執行查詢的事務你會將該屬性設爲true,如果出現了更新、插入或是刪除語句時只讀事務就會失敗)
aop:config指定了一個aop:pointcut去引用上邊的advice。
這樣就通過AOP的攔截機制實現了事務,當然你還要用Spring的方式自己配置UserDAO和UserService。
二、 Annotation方式
第一步,首先看一下web.xml,如下:
<?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"
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>Archetype Created Web Application</display-name>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:/spring-*.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<servlet>
<servlet-name>lei-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:/lei-dispatcher-servlet.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>lei-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
第二步,spring-hibernate配置,見以下spring-hibernate.xml配置
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
">
<!-- Hibernate4 -->
<!-- 加載資源文件 其中包含變量信息,必須在Spring配置文件的最前面加載,即第一個加載-->
<context:property-placeholder location="classpath:persistence-mysql.properties" />
<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan">
<list>
<!-- 可以加多個包 -->
<value>com.lei.demo.entity</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
<prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
<!-- <prop key="hibernate.current_session_context_class">thread</prop> -->
</props>
</property>
</bean>
<!-- 數據庫映射 -->
<!-- class="org.apache.tomcat.dbcp.dbcp.BasicDataSource" -->
<!-- class="org.springframework.jdbc.datasource.DriverManagerDataSource" -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}" />
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.user}" />
<property name="password" value="${jdbc.pass}" />
</bean>
<!-- 配置Hibernate事務管理器 -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<!-- 配置事務異常封裝 -->
<bean id="persistenceExceptionTranslationPostProcessor"
class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />
</beans>
第一節中xml配置事務中需要通過配置tx:advice和aop:config來增加事務的功能。此處採用全註釋方法,這兩個配置節就不需要了。
相應的需要在視圖解析配置中啓用註釋,如下lei-dispatcher-servlet.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
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/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
">
<!-- 啓動自動掃描 該包下所有的Bean(@Controller) -->
<context:component-scan base-package="com.lei.demo" />
<!-- 基於註釋的事務,當註釋中發現@Transactional時,使用id爲“transactionManager”的事務管理器 -->
<!-- 如果沒有設置transaction-manager的值,則spring以缺省默認的事務管理器來處理事務,默認事務管理器爲第一個加載的事務管理器 -->
<tx:annotation-driven transaction-manager="transactionManager"/>
<!-- 定義視圖解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/user/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
</beans>
UserDAO如下
package com.lei.demo.dao;
import java.util.List;
import javax.annotation.Resource;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.stereotype.Repository;
import com.lei.demo.entity.Users;
@Repository
public class UsersDAO {
@Resource(name="sessionFactory")
private SessionFactory sessionFactory;
public void setSessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
}
public SessionFactory getSessionFactory() {
return sessionFactory;
}
public List<Users> getAllUser(){
String hsql="from users";
Session session = sessionFactory.getCurrentSession();
Query query = session.createQuery(hsql);
return query.list();
}
}
UserService.java如下
package com.lei.demo.service;
import javax.annotation.Resource;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import com.lei.demo.dao.*;
@Service("userService")
public class UserService {
@Resource
private UsersDAO userDao;
@Transactional
public int userCount(){
return userDao.getAllUser().size();
}
public UsersDAO getUserDao() {
return userDao;
}
public void setUserDao(UsersDAO userDao) {
this.userDao = userDao;
}
}
這裏,方法名userCount上加入@Transactional,說明這個方法要啓用事務。如果類名UserService上加入@Transactional,則表明這個類中的所有方法都會啓用事務。
如果配有多個transactionManager,例如配置有transactionManager1,和transactionManager2,則可以通過@Transactional(“transactionManager1”),的方式指定使用哪個數據源的事務。
源代碼下載:
http://www.oschina.net/code/snippet_1764868_35775
原文出自:http://www.cnblogs.com/leiOOlei/p/3725911.html
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