J2EE系列之Spring4学习笔记（十四）--Spring4整合Struts2和Hibernate4

上一篇博客搭建了S2SH框架，这一篇博客讲述一个实例。

Spring支持泛型注入，所以DAO层变得非常简化。

1.在com.test.dao包中新建接口BaseDao：

package com.test.dao;import java.io.Serializable;import java.util.List;/** * 基础数据库操作类 *  * @author www.test.com *  */public interface BaseDao<T> {/** * 保存一个对象 *  * @param o * @return */public Serializable save(T o);/** * 删除一个对象 *  * @param o */public void delete(T o);/** * 更新一个对象 *  * @param o */public void update(T o);/** * 保存或更新对象 *  * @param o */public void saveOrUpdate(T o);/** * 查询 *  * @param hql * @return */public List<T> find(String hql);/** * 查询集合 *  * @param hql * @param param * @return */public List<T> find(String hql, Object[] param);/** * 查询集合 *  * @param hql * @param param * @return */public List<T> find(String hql, List<Object> param);/** * 查询集合(带分页) *  * @param hql * @param param * @param page *            查询第几页 * @param rows *            每页显示几条记录 * @return */public List<T> find(String hql, Object[] param, Integer page, Integer rows);/** * 查询集合(带分页) *  * @param hql * @param param * @param page * @param rows * @return */public List<T> find(String hql, List<Object> param, Integer page, Integer rows);/** * 获得一个对象 *  * @param c *            对象类型 * @param id * @return Object */public T get(Class<T> c, Serializable id);/** * 获得一个对象 *  * @param hql * @param param * @return Object */public T get(String hql, Object[] param);/** * 获得一个对象 *  * @param hql * @param param * @return */public T get(String hql, List<Object> param);/** * select count(*) from 类 *  * @param hql * @return */public Long count(String hql);/** * select count(*) from 类 *  * @param hql * @param param * @return */public Long count(String hql, Object[] param);/** * select count(*) from 类 *  * @param hql * @param param * @return */public Long count(String hql, List<Object> param);/** * 执行HQL语句 *  * @param hql * @return 响应数目 */public Integer executeHql(String hql);/** * 执行HQL语句 *  * @param hql * @param param * @return 响应数目 */public Integer executeHql(String hql, Object[] param);/** * 执行HQL语句 *  * @param hql * @param param * @return */public Integer executeHql(String hql, List<Object> param);}

这里使用了泛型，把一些常用的数据库操作保存到这里。

2.新建这个接口的实现类BaseDaoImpl：

package com.test.dao.impl;import java.io.Serializable;import java.util.List;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.test.dao.BaseDao;@Repository("baseDao")@SuppressWarnings("all")public class BaseDaOImpl<T> implements BaseDao<T> {private SessionFactory sessionFactory;public SessionFactory getSessionFactory() {return sessionFactory;}@Autowiredpublic void setSessionFactory(SessionFactory sessionFactory) {this.sessionFactory = sessionFactory;}private Session getCurrentSession() {return sessionFactory.getCurrentSession();}public Serializable save(T o) {return this.getCurrentSession().save(o);}public void delete(T o) {this.getCurrentSession().delete(o);}public void update(T o) {this.getCurrentSession().update(o);}public void saveOrUpdate(T o) {this.getCurrentSession().saveOrUpdate(o);}public List<T> find(String hql) {return this.getCurrentSession().createQuery(hql).list();}public List<T> find(String hql, Object[] param) {Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.length > 0) {for (int i = 0; i < param.length; i++) {q.setParameter(i, param[i]);}}return q.list();}public List<T> find(String hql, List<Object> param) {Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.size() > 0) {for (int i = 0; i < param.size(); i++) {q.setParameter(i, param.get(i));}}return q.list();}public List<T> find(String hql, Object[] param, Integer page, Integer rows) {if (page == null || page < 1) {page = 1;}if (rows == null || rows < 1) {rows = 10;}Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.length > 0) {for (int i = 0; i < param.length; i++) {q.setParameter(i, param[i]);}}return q.setFirstResult((page - 1) * rows).setMaxResults(rows).list();}public List<T> find(String hql, List<Object> param, Integer page, Integer rows) {if (page == null || page < 1) {page = 1;}if (rows == null || rows < 1) {rows = 10;}Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.size() > 0) {for (int i = 0; i < param.size(); i++) {q.setParameter(i, param.get(i));}}return q.setFirstResult((page - 1) * rows).setMaxResults(rows).list();}public T get(Class<T> c, Serializable id) {return (T) this.getCurrentSession().get(c, id);}public T get(String hql, Object[] param) {List<T> l = this.find(hql, param);if (l != null && l.size() > 0) {return l.get(0);} else {return null;}}public T get(String hql, List<Object> param) {List<T> l = this.find(hql, param);if (l != null && l.size() > 0) {return l.get(0);} else {return null;}}public Long count(String hql) {return (Long) this.getCurrentSession().createQuery(hql).uniqueResult();}public Long count(String hql, Object[] param) {Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.length > 0) {for (int i = 0; i < param.length; i++) {q.setParameter(i, param[i]);}}return (Long) q.uniqueResult();}public Long count(String hql, List<Object> param) {Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.size() > 0) {for (int i = 0; i < param.size(); i++) {q.setParameter(i, param.get(i));}}return (Long) q.uniqueResult();}public Integer executeHql(String hql) {return this.getCurrentSession().createQuery(hql).executeUpdate();}public Integer executeHql(String hql, Object[] param) {Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.length > 0) {for (int i = 0; i < param.length; i++) {q.setParameter(i, param[i]);}}return q.executeUpdate();}public Integer executeHql(String hql, List<Object> param) {Query q = this.getCurrentSession().createQuery(hql);if (param != null && param.size() > 0) {for (int i = 0; i < param.size(); i++) {q.setParameter(i, param.get(i));}}return q.executeUpdate();}}

Spring支持泛型注入后，Dao层写这两个文件就差不多了。在Spring出来以前，一般是有多少个模块就要写多少个dao，非常的麻烦。

这个实现类使用了注解@Repository("baseDAO")，这里说明一下，上一节的配置中在Spring配置文件中配置了自动构建加载bean<context:component-scan base-package="com.test" />，这样的话Spring就会扫描com.test包下的所有类。当扫描到@Repository("baseDAO")时，Spring就会自动创建一个这个类的bean，这个bean的id就是baseDAO，这个bean可以注入到其它的地方去。这里面用到了SessionFactory对象，我们在spring的配置文件中定义了SessionFactory对象的实例，要把这个实例注入给这个对象，这里使用@Autowired来标注对象的set方法，这样的话Spring就会自动把配置文件中手动定义的bean注入到这个对象中。

3.新建实体类User：

package com.test.entity;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.Table;import org.hibernate.annotations.GenericGenerator;@Entity@Table(name="t_user")public class User {private Integer id;private String userName;private String password;@Id@GenericGenerator(name = "generator", strategy = "native")@GeneratedValue(generator = "generator")@Column(name = "id", length=11)public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}@Column(name = "userName", length = 20)public String getUserName() {return userName;}public void setUserName(String userName) {this.userName = userName;}@Column(name = "password", length = 20)public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}}

这里使用注解的方式配置生成的数据库表。注解的意思在讲Hibernate的时候讲到了。

4.在com.test.service包下新建事务UserService接口：

package com.test.service;import java.util.List;import com.test.entity.User;public interface UserService {public void saveUser(User user);public void updateUser(User user);public User findUserById(int id);public void deleteUser(User user);public List<User> findAllList();public User findUserByNameAndPassword(User user);}

5.写这个接口的实现类UserServiceImpl：

package com.test.service.impl;import java.util.List;import javax.annotation.Resource;import org.springframework.stereotype.Service;import com.test.dao.BaseDao;import com.test.entity.User;import com.test.service.UserService;@Service("userService")public class UserServiceImpl implements UserService{@Resourceprivate BaseDao<User> baseDao;@Overridepublic void saveUser(User user) {// TODO Auto-generated method stubbaseDao.save(user);}@Overridepublic void updateUser(User user) {// TODO Auto-generated method stubbaseDao.update(user);}@Overridepublic User findUserById(int id) {return baseDao.get(User.class, id);}@Overridepublic void deleteUser(User user) {baseDao.delete(user);}@Overridepublic List<User> findAllList() {return baseDao.find("from User");}@Overridepublic User findUserByNameAndPassword(User user) {return baseDao.get("from User u where u.userName=? and u.password=?", new Object[]{user.getUserName(),user.getPassword()});}}

这里使用@Service("userService")注解来注解这个类，Spring扫描到这个类的时候会自动创建一个这个类的bean，bean的id是userService。在这个类中需要一个BaseDao对象的实例。这里使用@Resource来注解这个对象，这样的话Spring会自动的给这个对象注入值，而不用手动注入。这里要注意的是，BaseDao对象的名字baseDao一定要与BaseDaoImpl类的注解id相同。

6.新建action层类UserAction：这一层是struts2层

package com.test.action;import javax.annotation.Resource;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpSession;import org.apache.struts2.interceptor.ServletRequestAware;import org.springframework.stereotype.Controller;import com.test.entity.User;import com.test.service.UserService;import com.opensymphony.xwork2.ActionSupport;@Controllerpublic class UserAction extends ActionSupport implements ServletRequestAware{/** *  */private static final long serialVersionUID = 1L;private HttpServletRequest request;@Resourceprivate UserService userService;private User user;private String error;public User getUser() {return user;}public void setUser(User user) {this.user = user;}public String getError() {return error;}public void setError(String error) {this.error = error;}public String login()throws Exception{HttpSession session=request.getSession();User currentUser=userService.findUserByNameAndPassword(user);if(currentUser!=null){session.setAttribute("currentUser", currentUser);return SUCCESS;}else{error="用后名或者密码错误！";return ERROR;}}@Overridepublic void setServletRequest(HttpServletRequest request) {// TODO Auto-generated method stubthis.request=request;}}

Struts2层的类也由Spring管理，使用@Controller进行注解，这样的话Struts2的bean就会由Spring来管理。这里要用到UserService对象，使用@Resource对这个对象进行注解，这样的话Spring就会自动给这个对象注入值，这里要注意命名，名字要与Spring生成的UserServiceImpl的bean的id相同。

这里定义了User对象user用来接收从前台传入的对象，定义error对象用来当登录失败的时候向前台传输错误信息。注意一定要生成这两个对象的get和set函数。

定义一个login函数，用来判断前台输入的用户是否存在。

7.配置struts配置文件struts.xml：

<?xml version="1.0" encoding="UTF-8"?>  <!DOCTYPE struts PUBLIC      "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"      "http://struts.apache.org/dtds/struts-2.3.dtd">        <struts>      <constant name="struts.action.extension" value="action" />            <package name="s2sh" namespace="/user" extends="struts-default">    <action name="user_*" method="{1}" class="com.test.action.UserAction">    <result name="success">/success.jsp</result>    <result name="error">/index.jsp</result>    </action>    </package>      </struts>   

8.修改index.jsp文件为：

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body><form action="${pageContext.request.contextPath }/user/user_login.action" method="post">userName:<input type="text" name="user.userName" value="${user.userName }"/><br/>password:<input type="password" name="user.password" value="${user.password }"/><br/><input type="submit" value="login"/><font color="red">${error }</font></form></body></html>

9.新建success.jsp为：

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body>欢迎：${currentUser.userName }</body></html>

10.在mysql数据库中创建一个名为test的数据库，运行程序，给生成的数据表t_user插入数据：

打开浏览器：

输入正确的用户名和密码后点击login，跳转到了success.jsp页面。

输入错误的用户名和密码后：