Spring与Hibernate整合之通用Dao的实现

在上一篇文章中写了如何直接利用HibernateTemplate进行数据库操作，但在一般的项目中很少直接得到HibernateTemplate的
Bean对象从而操作数据库的，下面就简要介绍一下实现通用的数据库操作对象Dao类：

1、最基本的数据库操作接口BaseDao<T>:

import java.io.Serializable;
import java.util.List;

public interface BaseDao<T> {
    
    Serializable save (T entity);
    
    void delete (T entity);
    void delete (Class<T> clazz,Serializable id);
    
    void update(T entity);
    
    T get(Class<T> clazz,Serializable id);
    
    List<T> findAll(Class<T> clazz);
    
    List<T> findAll(Class<T> clazz,String where);
    
    
}

2、实现BaseDao<T>的实现类BaseDaoImpl<T>：

import java.io.Serializable;
import java.util.List;

import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

public class BaseDaoImpl<T> extends HibernateDaoSupport implements BaseDao<T>{

    @Override
    public Serializable save(T entity) {
        // TODO Auto-generated method stub
        return getHibernateTemplate().save(entity);
    }

    @Override
    public void delete(T entity) {
        // TODO Auto-generated method stub
        getHibernateTemplate().delete(entity);
        
    }

    @Override
    public void delete(Class clazz, Serializable id) {
        // TODO Auto-generated method stub
        delete(get(clazz,id));
        
    }

    @Override
    public void update(T entity) {
        // TODO Auto-generated method stub
        getHibernateTemplate().saveOrUpdate(entity);
        
    }

    @Override
    public T get(Class clazz, Serializable id) {
        // TODO Auto-generated method stub
        return (T) getHibernateTemplate().get(clazz, id);
    }

    @Override
    public List<T> findAll(Class clazz) {
        // TODO Auto-generated method stub
        return (List<T>) getHibernateTemplate().find("select en from "+clazz.getSimpleName()+" en");
    }

    @Override
    public List findAll(Class clazz, String where) {
        // TODO Auto-generated method stub
        return getHibernateTemplate().find("select en from "+clazz.getSimpleName()+" en where "+where);
    }

}

3、实体User：

import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

@Entity
public class User {

    @Id
    @Column(name="user_id")
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    private Integer id;
    @Column(name="user_name")
    private String name;
    private String pass;
    @Temporal(TemporalType.DATE)
    private Date birth;
    
    
    
    public User() {
        
    }
    
    
    public User( String name, String pass, Date birth) {
        super();
        this.name = name;
        this.pass = pass;
        this.birth = birth;
    }
    
    public Integer getId() {
        return id;
    }


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


    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPass() {
        return pass;
    }
    public void setPass(String pass) {
        this.pass = pass;
    }


    public Date getBirth() {
        return birth;
    }


    public void setBirth(Date birth) {
        this.birth = birth;
    }
    
    
}

4、针对User类的数据库操作Dao的接口，由于继承了BaseDao<User>，基本的函数接口也不用再写了，空的接口是为了日后的扩展：

import com.csu.comm.dao.BaseDao;
import com.csu.domain.User;

public interface UserDao extends BaseDao<User>{

}

5、实现了BaseDao<User>的类UserDaoImpl，也因为继承了BaseDaoImpl<User>，基本的操作已经都实现了，空体也是为了日后的扩展：

import java.io.Serializable;
import java.util.List;

import com.csu.comm.dao.BaseDaoImpl;
import com.csu.dao.UserDao;
import com.csu.domain.User;

public class UserDaoImpl extends BaseDaoImpl<User> implements UserDao {


}

6、c3p0数据库连接池所需要的数据库配置信息，放置在jdbc.properties文件中，这样也方便日后修改只需要改动属性文件，
而不需要改动配置文件：

user=root
password=7890
driverClass=com.mysql.jdbc.Driver
jdbcUrl=jdbc:mysql://localhost:3306/spring
maxPoolSize=200
minPoolSize=2
initialPoolSize=2

7、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>
        <!-- hibernate 所需的配置信息 -->
        <property name="show_sql">true</property>
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property><!--方言-->
        <property name="format_sql">true</property>
        <property name="hbm2ddl.auto">update</property>
        
        <!-- hibernate 指定映射类 -->
        <mapping class="com.csu.domain.User"/>
        
    </session-factory>
    
</hibernate-configuration>

8、spring的配置文件：

<?xml version="1.0" encoding="UTF-8"?>

<!-- 整个Spring 文件的根元素就是beans -->
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util.xsd
        
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        ">

       <!-- *****************配置数据源*********************** -->
      
       <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
       
           <property name="locations">
               <!-- 列出需要读取的属性文件 -->
               <list>
                   <value>classpath:jdbc.properties</value>
               </list>
           </property>
               
       </bean>
           
       <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
           p:user="${user}"
           p:password="${password}"
           p:driverClass="${driverClass}"
           p:jdbcUrl="${jdbcUrl}"
           p:maxPoolSize="${maxPoolSize}"
           p:minPoolSize="${minPoolSize}"
           p:initialPoolSize="${initialPoolSize}"
       />
       <!-- *****************配置数据源*********************** -->
    
    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"
    p:dataSource-ref="dataSource"
    p:configLocation="classpath:hibernate.cfg.xml"
    />
    
    <!--因为UserDaoImpl继承了BaseDaoImpl<T>， BaseDaoImpl<T> 继承了 HibernateDaoSupport，HibernateDaoSupport有setSessionFactory函数-->
    <bean id="userDao" class="com.csu.dao.impl.UserDaoImpl"
        p:sessionFactory-ref="sessionFactory"
    
    />
    
</beans>

10、测试主类：

import java.sql.SQLException;
import java.util.Date;
import java.util.List;

import org.hibernate.FlushMode;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.orm.hibernate3.HibernateCallback;
import org.springframework.orm.hibernate3.HibernateTemplate;

import com.csu.dao.UserDao;
import com.csu.domain.User;


public class SpHiTest {

    public static void main(String[] args) {
        ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");
        
        UserDao userDao = ctx.getBean("userDao",UserDao.class);
        List<User> users = userDao.findAll(User.class);
        for(Object u : users){
            System.out.println(((User) u).getName());
        }
        
    }
}

 11、结果;