spring之整合Hibernate

spring整合Hibernate整合什么？

1.让IOC容器来管理Hibernate的SessionFactory。

2.让Hibernate使用上spring的声明式事务。

整合步骤：

1.加入Hibernate。

2.加入spring。

3.整合。

一、加入Hibernate

1.加入相应jar包

加入Hibernate所需的依赖包：

将以上包加入到build path。 

加入连接数据库所需的依赖包：

将以上包加入到build path。 

2.添加Hibernate配置文件：hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <!-- 配置Hibernate的 基本属性-->
        <!-- 1.数据源需配置到IOC容器中，此处不再需要配置数据源 -->
        <!-- 2.关联的.hbm.xml也在IOC容器配置SessionFactory实例时再进行配置 -->
        <!-- 3.配置Hibernate的基本属性：方言、SQL显示及格式化，生成数据表的策略以及二级缓存等 -->
        <property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
        <property name="hibernate.show_sql">true</property>
        <property name="hibernate.format_sql">true</property>    
        <property name="hibernate.hbm2ddl.auto">update</property>
        <!-- 配置二级缓存相关的属性 -->
    </session-factory>
</hibernate-configuration>

3.添加实体类以及其hbm配置文件

Account.java

package com.gong.spring.hibernate.entities;

public class Account {

    private Integer id;
    private String username;
    private int balance;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public int getBalance() {
        return balance;
    }

    public void setBalance(int balance) {
        this.balance = balance;
    }

}

Book.java

package com.gong.spring.hibernate.entities;

public class Book {

    private Integer id;
    private String bookName;
    private String isbn;
    private int price;
    private int stock;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getBookName() {
        return bookName;
    }

    public void setBookName(String bookName) {
        this.bookName = bookName;
    }

    public String getIsbn() {
        return isbn;
    }

    public void setIsbn(String isbn) {
        this.isbn = isbn;
    }

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }

    public int getStock() {
        return stock;
    }

    public void setStock(int stock) {
        this.stock = stock;
    }

}

Account.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 2020-1-9 11:56:28 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
    <class name="com.gong.spring.hibernate.entities.Account" table="SH_ACCOUNT">
        <id name="id" type="java.lang.Integer">
            <column name="ID" />
            <generator class="native" />
        </id>
        <property name="username" type="java.lang.String">
            <column name="USERNAME" />
        </property>
        <property name="balance" type="int">
            <column name="BALANCE" />
        </property>
    </class>
</hibernate-mapping>

Book.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 2020-1-9 11:56:28 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
    <class name="com.gong.spring.hibernate.entities.Book" table="SH_BOOK">
        <id name="id" type="java.lang.Integer">
            <column name="ID" />
            <generator class="native" />
        </id>
        <property name="bookName" type="java.lang.String">
            <column name="BOOKNAME" />
        </property>
        <property name="isbn" type="java.lang.String">
            <column name="ISBN" />
        </property>
        <property name="price" type="int">
            <column name="PRICE" />
        </property>
        <property name="stock" type="int">
            <column name="STOCK" />
        </property>
    </class>
</hibernate-mapping>

这里需要说明的是table="SH_BOOK"中SH是表的前缀，我们在写hql语句时不用带上，系统会自动识别。

二、加入spring

1.加入相应的jar包

加入spring所需的jar包：

将以上依赖包加入到build path。

2.加入spring配置文件，并进行整合

db.propertites

jdbc.user=root
jdbc.password=123456
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql:///spring

jdbc.initPoolSize=5
jdbc.maxPoolSize=10

applicationContex.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:aop="http://www.springframework.org/schema/aop"
    xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
    
    <!-- 配置自动扫描的包 -->
    <context:component-scan base-package="com.gong.spring.hibernate"></context:component-scan>
    
    <!-- 配置数据源 -->
    <!-- 导入资源文件 -->
    <context:property-placeholder location="classpath:db.properties"/>
    
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>

        <property name="initialPoolSize" value="${jdbc.initPoolSize}"></property>
        <property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property>
    </bean>
    
    <!-- 配置 Hibernate 的 SessionFactory 实例: 通过 Spring 提供的 LocalSessionFactoryBean 进行配置 -->
    <bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <!-- 配置数据源属性 -->
        <property name="dataSource" ref="dataSource"></property>
        <!-- 配置 hibernate 配置文件的位置及名称 -->
        <property name="configLocation" value="classpath:hibernate.cfg.xml"></property>
        <!-- 使用 hibernateProperties 属相来配置 Hibernate 原生的属性 -->
        <!-- 
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
            </props>
        </property>
        -->
        <!-- 配置 hibernate 映射文件的位置及名称, 可以使用通配符 -->
        <property name="mappingLocations" 
            value="classpath:com/gong/spring/hibernate/entities/*.hbm.xml"></property>
    </bean>

    <!-- 配置 Spring 的声明式事务 -->
    <!-- 1. 配置事务管理器 -->
    <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>

    <!-- 2. 配置事务属性, 需要事务管理器 -->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="get*" read-only="true"/>
            <tx:method name="purchase" propagation="REQUIRES_NEW"/>
            <tx:method name="*"/>
        </tx:attributes>
    </tx:advice>

    <!-- 3. 配置事务切点, 并把切点和事务属性关联起来 -->
    <aop:config>
        <aop:pointcut expression="execution(* com.gong.spring.hibernate.service.*.*(..))" 
            id="txPointcut"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPointcut"/>
    </aop:config>

</beans>

需要注意：假设用的是navicat操作Mysql数据库，对于所连接的数据库，先不要打开，否则不会生成相应的数据表。同时，有两种方式配置hibernate的配置文件，一种是引用外部配置，一种是直接在applicaitonContext.xml文件中进行配置。

最后我们在com.gong.spring.hibernate.test中新建一个SpringHibernateTest.java进行测试：

package com.gong.spring.hibernate.test;

import java.sql.SQLException;
import java.util.Arrays;

import javax.sql.DataSource;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;


public class SpringHibernateTest {

    private ApplicationContext ctx = null;
    
    {
        ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
    }
    
    @Test
    public void testDataSource() throws SQLException {
        DataSource dataSource = ctx.getBean(DataSource.class);
        System.out.println(dataSource.getConnection());
    }

}

执行testDataSource方法，在数据库hb中会生成两个实体类的表：

3.进行代码测试

现在的目录结构如下：

使用基于注解的方式来配置bean，需要先在applicationContext.xml中加入：

　　 <!-- 配置自动扫描的包 -->
    <context:component-scan base-package="com.gong.spring.hibernate"></context:component-scan>

BookShopDao.java

package com.gong.spring.hibernate.dao;

public interface BookShopDao {
    
    //根据书号获取书的单价
    public int findBookPriceByIsbn(String isbn);
    //更新书的库存，使书号对应的库存-1
    public void updateBookStock(String isbn);
    //更新账户余额：使username的balance-price
    public void updateUserAccount(String username, int price);
}

BookShopDaoImpl.java

package com.gong.spring.hibernate.dao.impl;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import com.gong.spring.hibernate.dao.BookShopDao;
import com.gong.spring.hibernate.exceptions.BookStockException;
import com.gong.spring.hibernate.exceptions.UserAccountException;

@Repository
public class BookShopDaoImpl implements BookShopDao {
    @Autowired
    private SessionFactory sessionFactory;
    
    //获取当前绑定的session
    private Session getSession() {
        return sessionFactory.getCurrentSession();
    }
    @Override
    public int findBookPriceByIsbn(String isbn) {
        String hql = "SELECT b.price FROM Book b WHERE b.isbn = ?";
        Query query = getSession().createQuery(hql).setString(0, isbn);
        return (Integer) query.uniqueResult();
    }

    @Override
    public void updateBookStock(String isbn) {
        //验证书的库存是否充足
        String hql2 = "SELECT b.stock FROM Book b WHERE b.isbn = ?";
        //检查书的库存是否足够，如果不够，就抛出异常
        int stock = (int) getSession().createQuery(hql2).setString(0, isbn).uniqueResult();
        if(stock == 0){
            throw new BookStockException("库存不足!");
        }    
        String hql = "UPDATE Book b set b.stock = b.stock-1 WHERE b.isbn = ?";
        getSession().createQuery(hql).setString(0, isbn).executeUpdate();
    }

    @Override
    public void updateUserAccount(String username, int price) {
        String hql2 = "SELECT a.balance FROM Account a WHERE a.username = ?";
        int balance = (int) getSession().createQuery(hql2).setString(0, username).uniqueResult();
        if(balance < price){
            throw new UserAccountException("余额不足!");
        }
        
        String hql = "UPDATE Account a SET a.balance = a.balance - ? WHERE a.username = ?";
        getSession().createQuery(hql).setInteger(0, price).setString(1, username).executeUpdate();
    }

}

这里值得一提的是，hql语句和sql语句是有区别的，会将数据表当作对象来看，因此数据表的首字母要大写。

BookShopException.java和UserAccountException.java是我们自己定义的异常。

BookShopException.java

package com.gong.spring.hibernate.exceptions;

public class BookStockException extends RuntimeException{

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    public BookStockException() {
        super();
        // TODO Auto-generated constructor stub
    }

    public BookStockException(String message, Throwable cause,
            boolean enableSuppression, boolean writableStackTrace) {
        super(message, cause, enableSuppression, writableStackTrace);
        // TODO Auto-generated constructor stub
    }

    public BookStockException(String message, Throwable cause) {
        super(message, cause);
        // TODO Auto-generated constructor stub
    }

    public BookStockException(String message) {
        super(message);
        // TODO Auto-generated constructor stub
    }

    public BookStockException(Throwable cause) {
        super(cause);
        // TODO Auto-generated constructor stub
    }

    
}

UserAccountException.java

package com.gong.spring.hibernate.exceptions;

public class UserAccountException extends RuntimeException{

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    public UserAccountException() {
        super();
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(String message, Throwable cause,
            boolean enableSuppression, boolean writableStackTrace) {
        super(message, cause, enableSuppression, writableStackTrace);
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(String message, Throwable cause) {
        super(message, cause);
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(String message) {
        super(message);
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(Throwable cause) {
        super(cause);
        // TODO Auto-generated constructor stub
    }

    
    
}

其实就是为异常取了个名字，然后改为自己想要输出的错误信息。

BookShopService.java（用于测试买单本书时候的事务）

package com.gong.spring.hibernate.service;

public interface BookShopService {
    
    public void purchase(String username, String isbn);
    
}

Cashier.java（用于测试买多本书时候的事务）

package com.gong.spring.hibernate.service;

import java.util.List;

public interface Cashier {

    public void checkout(String username, List<String> isbns);
    
}

BookShopServiceImpl.java

package com.gong.spring.hibernate.service.impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.gong.spring.hibernate.dao.BookShopDao;

import com.gong.spring.hibernate.service.BookShopService;

@Service
public class BookShopServiceImpl implements BookShopService {

    @Autowired
    private BookShopDao bookShopDao;

    public void purchase(String username, String isbn) {
        
        //1. 获取书的单价
        int price = bookShopDao.findBookPriceByIsbn(isbn);
        
        //2. 更新库存
        bookShopDao.updateBookStock(isbn);
        
        //3. 更新余额
        bookShopDao.updateUserAccount(username, price);
    }

}

CashierImpl.java

package com.gong.spring.hibernate.service.impl;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

import com.gong.spring.hibernate.service.BookShopService;
import com.gong.spring.hibernate.service.Cashier;

@Service
public class CashierImpl implements Cashier {
    
    @Autowired
    private BookShopService bookShopService;

    @Override
    public void checkout(String username, List<String> isbns) {
        for(String isbn: isbns){
            bookShopService.purchase(username, isbn);
        }
    }

}

最后，我们在SpringHibernateTest.java中进行测试：

package com.gong.spring.hibernate.test;

import java.sql.SQLException;
import java.util.Arrays;

import javax.sql.DataSource;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.gong.spring.hibernate.service.BookShopService;
import com.gong.spring.hibernate.service.Cashier;


public class SpringHibernateTest {

    private ApplicationContext ctx = null;
    private BookShopService bookShopService = null;
    private Cashier cashier = null;
    
    {
        ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
        bookShopService = ctx.getBean(BookShopService.class);
        cashier = ctx.getBean(Cashier.class);
    }
    
    @Test
    public void testCashier(){
        cashier.checkout("AA", Arrays.asList("1001","1002"));
    }
    
    @Test
    public void testBookShopService(){
        bookShopService.purchase("AA", "1001");
    }
    
    @Test
    public void testDataSource() throws SQLException {
        DataSource dataSource = ctx.getBean(DataSource.class);
        System.out.println(dataSource.getConnection());
    }

}

首先我们往数据库中添加如下数据：

先测试 testBookShopService方法，结果如下：成功购买了一本java书。

再执行一次该方法：出现异常，余额不足，结果为：

说明我们的spring+hibernate事务是配置成功。

接下来我们测试事务的传播方式，即testCashier方法，首先我们将数据设置为：

第一次执行后的结果：成功买到两本书：

再执行一次：

只买了第一本书，第二本余额不足，因为我们在配置时指定了<tx:method name="purchase" propagation="REQUIRES_NEW"/>。如果设置 propagation="REQUIRD，那么就会一本都买不成功。具体原因可以参考之前所写的博客。

4.总结

至此，spring整合hibernate就基本完成了。

最后补充一些：

Spring Hibernate事务的流程：

（1）在方法执行之前获取session；

（2）把session和当前线程绑定，这样就可以在Dao中使用SessionFactory的getCurrentSession()来获取session；

（3）开启事务；

（4）若方法正常结束，即没有出现异常，则先提交事务，然后使当前线程绑定的session解除绑定，最后关闭session；

（5）若方法出现异常，则先回滚事务，然后使当前线程绑定的session解除绑定，最后关闭session；