使用Spring 2.5 和 Hibernate 3.2 开发MVC Web程序(基于annotation特性)
Spring 和 Hibernate 都支持annotation开发应用程序,无疑减少呢很多XML配置,使程序看起来更”干净”,下面我们以一个简单的例子来说明:
程序的开发环境:eclipse 3.2.2 + WTP + tomcat(推荐)
首先我们建一个动态的Web项目
修改WEB-INF/web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="ascweb" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>ascweb</display-name>
<!-- 载入Spring配置文件 -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext.xml</param-value><!-- 自动载入的spring配置 -->
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- 字符编码转换 -->
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>
org.springframework.web.filter.CharacterEncodingFilter
</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encodingFilter</filter-name>
<url-pattern>*.do</url-pattern>
</filter-mapping>
<!-- Spring MVC 的Servlet -->
<servlet>
<servlet-name>ascweb</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ascweb</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>index.do</welcome-file>
</welcome-file-list>
</web-app>
建立好这个文件之后,我们在WEB-INF目录下面建一个ascweb-servlet.xml文件,其实这个文件的命名就是Web.xml中servlet-name的名字加-servlet.xml.其文件内容如下:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<!-- 定义Spring MVC 的模板文件 -->
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/> <!-- 支持JSTL -->
<property name="prefix" value="WEB-INF/views/" /> <!-- 模板的路径 -->
<property name="suffix" value=".jsp" /> <!-- 模板文件的后缀-->
</bean>
<!-- 依赖注入到HelloController这个类 -->
<bean id="helloController" class="com.asc.web.ctl.HelloController">
<property name="viewName"> <!-- 设定viewName属性的值为hello -->
<value>hello</value>
</property>
<property name="userDao"> <!-- 设置属性userDao为Hibernate的Dao对象 -->
<ref bean="userDAOProxy" /> <!-- 注入一个bean(定义在Hibernate的配置文件里) -->
</property>
</bean>
</beans>
然后我们建立一个/WEB-INF/applicationContext.xml文件,其内容为:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
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-2.0.xsd">
<-- 数据源配置 -->
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName">
<value>com.microsoft.sqlserver.jdbc.SQLServerDriver</value>
</property>
<property name="url">
<value>jdbc:sqlserver://192.168.1.21:2433;DatabaseName=expert</value>
</property>
<property name="username">
<value>sa</value>
</property>
<property name="password">
<value>oilchem2006</value>
</property>
</bean>
<!-- hibernate3 session Bean-->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
<property name="dataSource"><!-- 注入数据源 -->
<ref local="dataSource" />
</property>
<property name="annotatedClasses"> <!-- 需要加载的Hibernate实体类(不需要hbm.xml了) -->
<list>
<value> com.asc.dao.User</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.SQLServerDialect</prop>
<prop key="hibernate.show_sql">true</prop>
</props>
</property>
</bean>
<!-- 事务管理 -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory">
<ref local="sessionFactory" />
</property>
</bean>
<!-- UserDAO bean-->
<bean id="userDAO" class=" com.asc.dao.UserDAO">
<property name="sessionFactory">
<ref local="sessionFactory" />
</property>
</bean>
<!-- 带事务处理的userDao 代理 -->
<bean id="userDAOProxy"
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
<property name="transactionManager">
<ref bean="transactionManager" />
</property>
<property name="target">
<ref local="userDAO" />
</property>
<property name="transactionAttributes">
<props>
<prop key="insert*">PROPAGATION_REQUIRED</prop>
<prop key="get*">PROPAGATION_REQUIRED,readOnly</prop>
</props>
</property>
</bean>
</beans>
然后我们开始写hibernate的代码,很简单
实体类User.java:
package com.asc.dao;
import javax.persistence.*;
import java.io.Serializable;
//指定表格的名称,注解方式
@SuppressWarnings("serial")
@Entity
@Table(name = "users2")
publicclass User implements Serializable {
public Integer id;
public String username;
public String password;
//主键,注解方式
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Integer getId() {
returnid;
}
publicvoid setId(Integer id) {
this.id = id;
}
public String getPassword() {
returnpassword;
}
publicvoid setPassword(String password) {
this.password = password;
}
public String getUsername() {
returnusername;
}
publicvoid setUsername(String username) {
this.username = username;
}
}
然后我们新建一个接口IUserDAO:
package com.asc.dao;
import java.util.List;
publicinterface IUserDAO {
publicabstractvoid insertUser(User user);
publicabstract List<User> selectUser();
}
我们再建一个接口的实现UserDAO:
package com.asc.dao;
import java.util.List;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
publicclass UserDAO extends HibernateDaoSupport implements IUserDAO{
//插入数据
publicvoid insertUser(User user) {
getHibernateTemplate().saveOrUpdate(user);
}
//查询数据
@SuppressWarnings("unchecked")
public List<User> selectUser(){
String sql="From User Order By id";
List<User> findByNamedQuery = getHibernateTemplate().find(sql);
return findByNamedQuery;
}
}
现在我们的Hibernate部分就全部写好了.简单吧,发现什么了吗,没有讨厌的hbm.xml文件呢,那些配置写道User这个实体类里了,这个是Java 5之后才有的功能,叫annotation(相当于元数据).
现在我们开始写MVC层
建立一个文件:
package com.asc.web.ctl;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import com.asc.dao.IUserDAO;
import com.asc.dao.User;
//还是注解方式,不用继承任何类或者实现任何接口
@Controller
publicclass HelloController{
private String viewName;
private IUserDAO userDao;
//在ascweb-servlet.xml里配置的,该属性已经被注入userDAOProxy接口了
public IUserDAO getUserDao() {
returnuserDao;
}
publicvoid setUserDao(IUserDAO userDao) {
this.userDao = userDao;
}
public String getViewName() {
returnviewName;
}
publicvoid setViewName(String viewName) {
this.viewName = viewName;
}
//注解其url映射
@SuppressWarnings("unchecked")
@RequestMapping("/hello.do")
public String index(ModelMap map,HttpServletRequest request,HttpServletResponse response) {
// map是用来设置View层数据的
map.put("a1", "Spring真好用");
request.getSession().setAttribute("a2", "测试Session");
List<User> list2 = userDao.selectUser();
map.put("a3", list2);
returnthis.viewName; //该属性被注入值hello了,就是渲染视图hello.jsp
}
}
现在我们可以做最后一部了.写View层,在WEB-INF/views里新建一个hello.jsp(还记得我们在配置Spring MVC层中配置view的路径是WEB-INF/views,后缀是jsp吗)
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<%@ taglib prefix="c" uri="/WEB-INF/c.tld"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>在此处插入标题</title>
</head>
<body>
测试: ${a1} ${a2}
<br />
<c:forEach var="list" items="${a3}">
<c:out value="${list.id}"></c:out>
<c:if test="${list.id % 2 == 0}">
<a href="#" style="color:red;border:1px #ececec solid"><c:out
value="${list.username}"></c:out></a>
</c:if>
<c:if test="${list.id % 2 != 0}">
<a href="#" style="color:green;border:1px #ececec solid"><c:out
value="${list.username}"></c:out></a>
</c:if>
<c:out value="${list.password}"></c:out>
<br />
</c:forEach>
</body>
</html>
我们再加入log4j.properties到src目录,配置日志显示.方便调试Ok,运行一下.