程序功能为注册用户，显示用户信息。分四层:jsp,action,service,DAO 1、在lib目录加入struts2与hibernate的包。我是用 2、在web.xml增加struts2的过滤器 3、注册表单,register.jsp:
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
My JSP 'register.jsp' starting page
用户名:
密码:
年龄:
4、建Model:建包com.model,类Person
package com.model;
import java.sql.Date;
public class Person {
private Integer id;
//最好用Integer而不是用int,后面查询需要Integer
private String username;
private String password;
private Integer age;
private Date registerDate;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Date getRegisterDate() {
return registerDate;
}
public void setRegisterDate(Date registerDate) {
this.registerDate = registerDate;
}
}
5、配置Model与数据库字段的映射，在src目录下添加Person.hbm.xml(不是严格要求的):
<?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>
<!-- name类名，table表名 -->
<class name="com.model.Person" table="person">
<!-- id标签表示主键 -->
<id name="id" column="id" type="int">
<!-- 自动增长 -->
<generator class="increment"></generator>
</id>
<!-- 下面是字段映射 name属性,column是字段 type数据库类型 -->
<property name="username" column="username" type="string"></property>
<property name="password" column="password" type="string"></property>
<property name="age" column="age" type="int"></property>
<property name="registerDate" column="registerDate" type="date"></property>
</class>
</hibernate-mapping>
6、配置Hibernate数据库连接,src目录下建hibernate.cfg.xml(可改名，但不建议),内容如下：
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<!-- 设置dialect属性可以使用该类型数据库特性 -->
<property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
<!-- 在命令行输出SQL语句 -->
<property name="show_sql">true</property>
<!-- Model属性与数据库字段的映射文件 -->
<mapping resource="Person.hbm.xml" />
</session-factory>
</hibernate-configuration>
注意，需要导入mysql jdbc驱动jar包. 7、数据库连接与关闭:包com.util类HibernateUtil
package com.util;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
private static SessionFactory sessionFactory;
//因为sessionFactory一旦生成就不需要关闭,即使配置文件修改也不会影响，所以放在静态代码片段中，类加载时就生成
static{
sessionFactory=new Configuration().configure().buildSessionFactory();
}
public static Session openSession()
{
Session session=sessionFactory.openSession();
return session;
}
public static void close(Session session)
{
if(session!=null)
{
session.close();
}
}
}
8、写DAO层(调用Hibernate API与数据库交互)，建包com.dao,接口PersonDAO,内容如下:
package com.dao;
import com.model.Person;
public interface PersonDAO {
public void savePerson(Person person);
public Person showPerson(Integer id);
}
一个保存用户(注册),一个返回指定ID的用户。 实现:包com.dao.impl,类PersonDAOImpl:
package com.dao.impl;
import org.hibernate.Transaction;
import com.dao.PersonDAO;
import com.model.Person;
import com.util.HibernateUtil;
public class PersonDAOImpl implements PersonDAO {
@Override
public void savePerson(Person person) {
//开启session,与HttpSession完全没有任何关系，相当于一个数据库连接对象
org.hibernate.Session session = HibernateUtil.openSession();
Transaction tx = session.beginTransaction();
//开启事务
try {
//插入
session.save(person);
tx.commit();
} catch (Exception ex) {
if (null != tx) {
tx.rollback();
//失败回滚
}
} finally {
//关闭session
HibernateUtil.close(session);
}
}
@Override
public Person showPerson(Integer id) {
// TODO Auto-generated method stub
org.hibernate.Session session = HibernateUtil.openSession();
//get方法取出对象
Person person = (Person) session.get(Person.class, id);
return person;
}
}
9、Service层，主要功能是逻辑处理，这里是与DAO层交互，即调用DAO层方法取出数据: 建com.service包,类PersonService：
package com.service;
import com.model.Person;
public interface PersonService {
public void savePerson(Person person);
public Person showPerson(Integer id);
}
实现类PersonServiceImpl,包com.service.impl中
package com.service.impl;
import com.dao.PersonDAO;
import com.dao.impl.PersonDAOImpl;
import com.model.Person;
import com.service.PersonService;
public class PersonServiceImpl implements PersonService {
@Override
public void savePerson(Person person) {
// TODO Auto-generated method stub
PersonDAO personDAO=new PersonDAOImpl();
personDAO.savePerson(person);
}
@Override
public Person showPerson(Integer id) {
// TODO Auto-generated method stub
PersonDAO personDAO=new PersonDAOImpl();
Person person=personDAO.showPerson(id);
return person;
}
}
10、建Action(接收用户请求，作简单的包装),包com.action，类PersonAction,这里把查询和注册的方法写在同一个action中。
package com.action;
import org.apache.struts2.ServletActionContext;
import com.model.Person;
import com.opensymphony.xwork2.ActionSupport;
import com.service.PersonService;
import com.service.impl.PersonServiceImpl;
public class PersonAction extends ActionSupport {
private String username;
private String password;
private Integer age;
private Integer id;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
/**
* 保存用户
* @return
* @throws Exception
*/
public String savePerson() throws Exception {
// TODO Auto-generated method stub
Person person=new Person();
person.setAge(age);
person.setPassword(password);
person.setUsername(username);
java.sql.Date registerDate=new java.sql.Date(new java.util.Date().getTime());
person.setRegisterDate(registerDate);
PersonService personService=new PersonServiceImpl();
personService.savePerson(person);
return SUCCESS;
}
/**
* 取用户
* @return
* @throws Exception
*/
public String showPerson() throws Exception{
PersonService personService=new PersonServiceImpl();
Person person=personService.showPerson(id);
ServletActionContext.getRequest().setAttribute("person", person);
return SUCCESS;
}
}
struts.xml中配置Action:
<package name="struts2_hibernate" extends="struts-default">
<action name="savePerson" class="com.action.PersonAction" method="savePerson">
</action>
<action name="showPerson" class="com.action.PersonAction" method="showPerson">
<result name="success">/showPerson.jsp</result>
</action>
</package>
savePerson没有写result，所以添加成功后返回404. 显示用户信息的jsp,showPerson.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
My JSP 'showPerson.jsp' starting page
${person.username }
${person.password }
${person.age }
启动服务器测试前，先在数据库中建好相应的表 注册用户:http://localhost:8080/hibernate/register.jsp 查看用户:http://localhost:8080/hibernate/showPerson.action?id=用户id