标签：ssh
因为这里写的是通用Dao功能，因此将它放置到core包里面。
1、定义通用Dao中的方法
BaseDao.java
package com.rk.core.dao;
import java.io.Serializable;
import java.util.List;
public interface BaseDao<T> {
void save(T entity);
void update(T entity);
void delete(Serializable id);
T findById(Serializable id);
List<T> findAll();
}2、通用Dao的实现
需要注意的地方：
（1）BaseDaoImpl类继承自HibernateDaoSupport类，并实现了BaseDao接口。
（2）在BaseDaoImpl构造方法中，我们通过反射获取了泛型T的真实类型
（3）在delete方法中，我们通过调用HibernateConfigurationUtils类的方法来获得实体类的主键属性。HibernateConfigurationUtils是一个自定义的类。
HibernateDaoSupport类 1、HibernateDaoSupport介绍 我们使用Hibernate进行数据库的访问，访问数据库的这一层代码称为DAO层。 spring帮开发者封装了一个HibernateDaoSupport类（位于org.springframework.orm.hibernate3.support包下），该类提供了获取HibernateTemplate的方法，而HibernateTemplate对象可以方便的进行数据库的CRUD操作，因此我们自己写的Dao层的代码可以继承HibernateDaoSupport类。 2、如何使用HibernateDaoSupport类？ 这里有一个前提要注意一下：我们是Spring和Hibernate整合的情况下使用HibernateDaoSupport。 首先，我们需要为HibernateDaoSupport类提供一个SessionFactory对象。 其次，我们可以通过调用HibernateDaoSupport类的getHibernateTemplate()方法得到一个HibernateTemplate对象。 最后，我们使用HibernateTemplate对象进行数据库操作。 假设我们最终会写一个UserDaoImpl类，那么UserDaoImpl类继承自BaseDaoImpl类，而BaseDaoImpl类继承自HibernateDaoSupport类。 Convenient super class for Hibernate-based data access objects. Requires a |
BaseDaoImpl.java
package com.rk.core.dao.impl;
import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import com.rk.core.dao.BaseDao;
import com.rk.core.utils.HibernateConfigurationUtils;
public class BaseDaoImpl<T> extends HibernateDaoSupport implements BaseDao<T> {
private Class<T> clazz;
@SuppressWarnings("unchecked")
public BaseDaoImpl() {
ParameterizedType pt = (ParameterizedType) this.getClass().getGenericSuperclass();
Type[] args = pt.getActualTypeArguments();
this.clazz = (Class<T>) args[0];
}
public void save(T entity) {
getHibernateTemplate().save(entity);
}
public void update(T entity) {
getHibernateTemplate().update(entity);
}
public void delete(Serializable id) {
String identifierPropertyName = HibernateConfigurationUtils.getIdentifierPropertyName(clazz);
Session session = getSession();
session.createQuery("delete from " + clazz.getSimpleName() + " where " + identifierPropertyName + "=?")
.setParameter(0, id).executeUpdate();
}
public T findById(Serializable id) {
return getHibernateTemplate().get(clazz, id);
}
@SuppressWarnings("unchecked")
public List<T> findAll() {
Session session = getSession();
Query query = session.createQuery("from " + clazz.getSimpleName());
return query.list();
}
}3、HibernateConfigurationUtils
主键属性，通过反射来获取
ApplicationContext对象-->Configuration对象-->PersistentClass对象-->获取类的主键属性
需要注意的是：
(1)HibernateConfigurationUtils 实现了 ApplicationContextAware 接口；ApplicationContextAware接口是位于org.springframework.context包下。
(2)HibernateConfigurationUtils类需要在bean-core.xml文件中进行注册，而bean-core.xml需要引入到applicationContext.xml文件中。
<bean class="com.rk.core.utils.HibernateConfigurationUtils"></bean>
ApplicationContextAware接口的定义如下： package org.springframework.context;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.Aware;
public interface ApplicationContextAware extends Aware
{
public abstract void setApplicationContext(ApplicationContext applicationcontext)
throws BeansException;
}我们可以看到ApplicationContextAware接口只有一个方法，它的作用是：让实现了ApplicationContextAware接口的类能够访问到ApplicationContext对象。 Interface to be implemented by any object that wishes to be notified of the |
HibernateConfigurationUtils.java
package com.rk.core.utils;
import org.hibernate.cfg.Configuration;
import org.hibernate.mapping.PersistentClass;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.orm.hibernate3.LocalSessionFactoryBean;
public class HibernateConfigurationUtils implements ApplicationContextAware {
// 1、ApplicationContext对象
private static ApplicationContext applicationContext;
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException
{
HibernateConfigurationUtils.applicationContext = applicationContext;
}
// 2、Configuration对象
private static Configuration configuration;
public static Configuration getConfiguration()
{
if(configuration == null)
{
// 取sessionFactory的时候要加上&
LocalSessionFactoryBean factory = (LocalSessionFactoryBean) applicationContext.getBean("&sessionFactory");
configuration = factory.getConfiguration();
}
return configuration;
}
public static void setConfiguration(Configuration configuration)
{
HibernateConfigurationUtils.configuration = configuration;
}
// 3、PersistentClass对象
private static <T> PersistentClass getPersistentClass(Class<T> clazz)
{
synchronized(HibernateConfigurationUtils.class)
{
PersistentClass pc = getConfiguration().getClassMapping(clazz.getSimpleName());
if(pc == null)
{
configuration = configuration.addClass(clazz);
pc = configuration.getClassMapping(clazz.getName());
}
return pc;
}
}
// 4、获取映射信息
// 4.1、获取类信息-主键属性
public static <T> String getIdentifierPropertyName(Class<T> clazz)
{
return getPersistentClass(clazz).getIdentifierProperty().getName();
}
}4、使用通用Dao
User.java
package com.rk.tax.entity;
import java.util.Date;
public class User {
private String id;
private String dept;
private String account;
private String name;
private String password;
private String headImg;
private boolean gender;
private String state;
private String mobile;
private String email;
private Date birthday;
private String memo;
//用户状态
public static String USER_STATE_VALID = "1";//有效
public static String USER_STATE_INVALID = "0";//无效
public User() {
}
public User(String id, String dept, String account, String name,
String password, String headImg, boolean gender, String state,
String mobile, String email, Date birthday, String memo) {
this.id = id;
this.dept = dept;
this.account = account;
this.name = name;
this.password = password;
this.headImg = headImg;
this.gender = gender;
this.state = state;
this.mobile = mobile;
this.email = email;
this.birthday = birthday;
this.memo = memo;
}
// {{ Properties
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getDept() {
return dept;
}
public void setDept(String dept) {
this.dept = dept;
}
public String getAccount() {
return account;
}
public void setAccount(String account) {
this.account = account;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getHeadImg() {
return headImg;
}
public void setHeadImg(String headImg) {
this.headImg = headImg;
}
public boolean isGender() {
return gender;
}
public void setGender(boolean gender) {
this.gender = gender;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public String getMobile() {
return mobile;
}
public void setMobile(String mobile) {
this.mobile = mobile;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMemo() {
return memo;
}
public void setMemo(String memo) {
this.memo = memo;
}
// }}
}User.hbm.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.rk.tax.entity" auto-import="true"> <class name="User" table="T_Users"> <id name="id" column="id" type="string" length="32"> <generator class="uuid.hex"></generator> </id> <property name="name" column="name" type="string" length="20" not-null="true"></property> <property name="dept" column="dept" type="string" length="20" not-null="true"></property> <property name="account" column="account" type="string" length="50" not-null="true"></property> <property name="password" column="password" type="string" length="50" not-null="true"></property> <property name="headImg" column="headImg" type="string" length="100"></property> <property name="gender" column="gender" type="boolean" not-null="true"></property> <property name="email" column="email" type="string" length="50"></property> <property name="mobile" column="mobile" type="string" length="20"></property> <property name="birthday" column="birthday" type="date" length="10" ></property> <property name="state" column="state" type="string" length="1"></property> <property name="memo" column="memo" type="string" length="200"></property> </class> </hibernate-mapping>
UserDao.java
package com.rk.tax.dao;
import com.rk.core.dao.BaseDao;
import com.rk.tax.entity.User;
public interface UserDao extends BaseDao<User> {
}UserDaoImpl.java
package com.rk.tax.dao.impl;
import com.rk.core.dao.impl.BaseDaoImpl;
import com.rk.tax.dao.UserDao;
import com.rk.tax.entity.User;
public class UserDaoImpl extends BaseDaoImpl<User> implements UserDao {
}标签：ssh
原文地址：http://lsieun.blog.51cto.com/9210464/1835776
