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>:
1 import java.io.Serializable; 2 import java.util.List; 3 4 public interface BaseDao<T> { 5 6 Serializable save (T entity); 7 8 void delete (T entity); 9 void delete (Class<T> clazz,Serializable id); 10 11 void update(T entity); 12 13 T get(Class<T> clazz,Serializable id); 14 15 List<T> findAll(Class<T> clazz); 16 17 List<T> findAll(Class<T> clazz,String where); 18 19 20 }
2、实现BaseDao<T>的实现类BaseDaoImpl<T>：
1 import java.io.Serializable; 2 import java.util.List; 3 4 import org.springframework.orm.hibernate3.support.HibernateDaoSupport; 5 6 public class BaseDaoImpl<T> extends HibernateDaoSupport implements BaseDao<T>{ 7 8 @Override 9 public Serializable save(T entity) { 10 // TODO Auto-generated method stub 11 return getHibernateTemplate().save(entity); 12 } 13 14 @Override 15 public void delete(T entity) { 16 // TODO Auto-generated method stub 17 getHibernateTemplate().delete(entity); 18 19 } 20 21 @Override 22 public void delete(Class clazz, Serializable id) { 23 // TODO Auto-generated method stub 24 delete(get(clazz,id)); 25 26 } 27 28 @Override 29 public void update(T entity) { 30 // TODO Auto-generated method stub 31 getHibernateTemplate().saveOrUpdate(entity); 32 33 } 34 35 @Override 36 public T get(Class clazz, Serializable id) { 37 // TODO Auto-generated method stub 38 return (T) getHibernateTemplate().get(clazz, id); 39 } 40 41 @Override 42 public List<T> findAll(Class clazz) { 43 // TODO Auto-generated method stub 44 return (List<T>) getHibernateTemplate().find("select en from "+clazz.getSimpleName()+" en"); 45 } 46 47 @Override 48 public List findAll(Class clazz, String where) { 49 // TODO Auto-generated method stub 50 return getHibernateTemplate().find("select en from "+clazz.getSimpleName()+" en where "+where); 51 } 52 53 }
3、实体User：
1 import java.util.Date; 2 3 import javax.persistence.Column; 4 import javax.persistence.Entity; 5 import javax.persistence.GeneratedValue; 6 import javax.persistence.GenerationType; 7 import javax.persistence.Id; 8 import javax.persistence.Temporal; 9 import javax.persistence.TemporalType; 10 11 @Entity 12 public class User { 13 14 @Id 15 @Column(name="user_id") 16 @GeneratedValue(strategy=GenerationType.IDENTITY) 17 private Integer id; 18 @Column(name="user_name") 19 private String name; 20 private String pass; 21 @Temporal(TemporalType.DATE) 22 private Date birth; 23 24 25 26 public User() { 27 28 } 29 30 31 public User( String name, String pass, Date birth) { 32 super(); 33 this.name = name; 34 this.pass = pass; 35 this.birth = birth; 36 } 37 38 public Integer getId() { 39 return id; 40 } 41 42 43 public void setId(Integer id) { 44 this.id = id; 45 } 46 47 48 public String getName() { 49 return name; 50 } 51 public void setName(String name) { 52 this.name = name; 53 } 54 public String getPass() { 55 return pass; 56 } 57 public void setPass(String pass) { 58 this.pass = pass; 59 } 60 61 62 public Date getBirth() { 63 return birth; 64 } 65 66 67 public void setBirth(Date birth) { 68 this.birth = birth; 69 } 70 71 72 }
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：
1 import com.csu.comm.dao.BaseDao; 2 import com.csu.domain.User; 3 4 public interface UserDao extends BaseDao<User>{ 5 6 }
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：
1 import java.io.Serializable; 2 import java.util.List; 3 4 import com.csu.comm.dao.BaseDaoImpl; 5 import com.csu.dao.UserDao; 6 import com.csu.domain.User; 7 8 public class UserDaoImpl extends BaseDaoImpl<User> implements UserDao { 9 10 11 }
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：
1 user=root 2 password=7890 3 driverClass=com.mysql.jdbc.Driver 4 jdbcUrl=jdbc:mysql://localhost:3306/spring 5 maxPoolSize=200 6 minPoolSize=2 7 initialPoolSize=2
7、hibernate配置文件hibernate.cfg.xml：
1 <?xml version='1.0' encoding='utf-8'?> 2 <!DOCTYPE hibernate-configuration PUBLIC 3 "-//Hibernate/Hibernate Configuration DTD 3.0//EN" 4 "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> 5 6 <hibernate-configuration> 7 8 <session-factory> 9 <!-- hibernate 所需的配置信息 --> 10 <property name="show_sql">true</property> 11 <property name="dialect">org.hibernate.dialect.MySQLDialect</property><!--方言--> 12 <property name="format_sql">true</property> 13 <property name="hbm2ddl.auto">update</property> 14 15 <!-- hibernate 指定映射类 --> 16 <mapping class="com.csu.domain.User"/> 17 18 </session-factory> 19 20 </hibernate-configuration>
8、spring的配置文件：
1 <?xml version="1.0" encoding="UTF-8"?> 2 3 <!-- 整个Spring 文件的根元素就是beans --> 4 <beans xmlns="http://www.springframework.org/schema/beans" 5 xmlns:p="http://www.springframework.org/schema/p" 6 xmlns:util="http://www.springframework.org/schema/util" 7 xmlns:context="http://www.springframework.org/schema/context" 8 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 9 xsi:schemaLocation="http://www.springframework.org/schema/beans 10 http://www.springframework.org/schema/beans/spring-beans.xsd 11 12 http://www.springframework.org/schema/util 13 http://www.springframework.org/schema/util/spring-util.xsd 14 15 http://www.springframework.org/schema/context 16 http://www.springframework.org/schema/context/spring-context.xsd 17 "> 18 19 <!-- *****************配置数据源*********************** --> 20 21 <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> 22 23 <property name="locations"> 24 <!-- 列出需要读取的属性文件 --> 25 <list> 26 <value>classpath:jdbc.properties</value> 27 </list> 28 </property> 29 30 </bean> 31 32 <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" 33 p:user="${user}" 34 p:password="${password}" 35 p:driverClass="${driverClass}" 36 p:jdbcUrl="${jdbcUrl}" 37 p:maxPoolSize="${maxPoolSize}" 38 p:minPoolSize="${minPoolSize}" 39 p:initialPoolSize="${initialPoolSize}" 40 /> 41 <!-- *****************配置数据源*********************** --> 42 43 <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean" 44 p:dataSource-ref="dataSource" 45 p:configLocation="classpath:hibernate.cfg.xml" 46 /> 47 48 <!--因为UserDaoImpl继承了BaseDaoImpl<T>， BaseDaoImpl<T> 继承了 HibernateDaoSupport，HibernateDaoSupport有setSessionFactory函数--> 49 <bean id="userDao" class="com.csu.dao.impl.UserDaoImpl" 50 p:sessionFactory-ref="sessionFactory" 51 52 /> 53 54 </beans>
10、测试主类：
1 import java.sql.SQLException; 2 import java.util.Date; 3 import java.util.List; 4 5 import org.hibernate.FlushMode; 6 import org.hibernate.HibernateException; 7 import org.hibernate.Session; 8 import org.springframework.context.ApplicationContext; 9 import org.springframework.context.support.ClassPathXmlApplicationContext; 10 import org.springframework.orm.hibernate3.HibernateCallback; 11 import org.springframework.orm.hibernate3.HibernateTemplate; 12 13 import com.csu.dao.UserDao; 14 import com.csu.domain.User; 15 16 17 public class SpHiTest { 18 19 public static void main(String[] args) { 20 ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml"); 21 22 UserDao userDao = ctx.getBean("userDao",UserDao.class); 23 List<User> users = userDao.findAll(User.class); 24 for(Object u : users){ 25 System.out.println(((User) u).getName()); 26 } 27 28 } 29 }
11、结果;
