整合s2sh，实现页面操作数据库

• 先说点废话

　　　　s2sh，就是struts2，spring，hibernate；s2作为表现层和控制器，hibernate作为持久层，spring作为业务层（充分应用IOC和AOP）。其实业务还是业务，只是依赖类通过spring来注入和管理，使得代码非常简洁（前提你得非常熟悉，不然就像在下一样即将发疯）；spring的应用主要是在管理对象的c创建（IOC）还有数据库事物的管理（AOP），今天熟悉了IOC的使用，写个demo记录一下。

• 准备事项

　　　　配置ssh的环境，主要是导包和创建配置文件。

　　　　

　　　　struts的配置文件struts.xml，hibernate的配置文件hibernate.cfg.xml,spring的配置文件applicationContext.xml；

　　　　以及修改web.xml。

• 整合例子

　　　　目录如下，仍然是mvc，model存表对象，service存数据库事物，dao存单个表操作，action是控制器。

　　　　

　　　　web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
    <display-name>SpringPractice</display-name>
    <welcome-file-list>
        <welcome-file>hello</welcome-file>
    </welcome-file-list>
   <filter>
    <filter-name>struts2</filter-name>
    <filter-class>
          org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
      </filter-class>
  </filter>
  <filter-mapping>
    <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping> 

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <context-param>
        <param-name>contextConfigLocation </param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>
</web-app>

　　　　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.enable.DynamicMethodInvocation" value="false" />
    <constant name="struts.devMode" value="true" />
    <!--  submit不换行 -->
    <constant name="struts.ui.theme" value="simple" />
    <constant name="struts.i18n.encoding" value="UTF-8"/>
    <!--整合spring-->
    <constant name="struts.objectFactory" value="spring" />
    <!-- Add packages here -->
    <package name="default" namespace="/" extends="struts-default">
        <!-- 测试action-->
        <!-- class对应applicationContext.xml的id，在applicationContext.xml上配置真是路径 -->
        <action name="add" class="add">
            <result name="success"></result>
        </action>
        <action name="delete" class="delete">
            <result name="success"></result>
        </action>
        <action name="testHello" class="Hello">
            <result name="success"></result>
        </action>
    </package>

</struts>

　　　　hibernate.xml 其实可以不要了，全部配在了applicationContext.xml

<?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="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.password">qwert1234</property>
        <property name="hibernate.connection.url">jdbc:mysql://3306:MyData?useSSL=true</property>
        <property name="hibernate.connection.username">root</property>

        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="connection.characterEncoding">utf-8</property>
        <property name="show_sql">true</property>
        -->
    </session-factory>
</hibernate-configuration>

　　　　applicationContext.xml

<?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.xsd"
    >
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="username" value="root"></property>
        <property name="password" value="qwert1234"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/MyData?useSSL=true"></property>
        <property name="driverClassName" value="com.mysql.jdbc.Driver" ></property>
    </bean>
    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <!-- <property name="configLocation" value="classpath:hibernate.cfg.xml"></property> -->
        <!-- 注入一个DataSource -->
        <property name="dataSource" ref="dataSource"></property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
                <prop key="hibernate.hbm2ddl.auto">false</prop>
                <prop key="hibernate.show_sql">true</prop>
            </props>
        </property>
        <property name="mappingResources">
            <list>
                <value>model/user.hbm.xml</value>
            </list>
        </property>
    </bean>
    <bean id="userDaoImpl" class="dao.userDaoImpl">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>
    <bean id="userService" class="service.UserService" scope="prototype">
         <property name="userDaoImpl" ref="userDaoImpl"></property>
    </bean>
    <!-- 配置action-->
     <bean id="add" class="action.addUserAction"  scope="prototype">
         <property name="userService" ref="userService"></property>
    </bean>
       <bean id="delete" class="action.deleteAction"  scope="prototype">
         <property name="userService" ref="userService"></property>
    </bean>
    <bean id="Hello" class="action.HelloAction" autowire="byName" scope="prototype">
    </bean>
</beans>

　　　　service对象里面有一个dao对象，是通过注入使用的；配置控制器的时候，把service注入进去，在此之前先实例化一个service对象；值得注意的是hibernate和spring的整合。

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="username" value="root"></property>
        <property name="password" value="qwert1234"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/MyData?useSSL=true"></property>
        <property name="driverClassName" value="com.mysql.jdbc.Driver" ></property>
    </bean>

　　　　首先配置dataSource，class可以配jdbc或者是其他的连接池。配完了这几行，hibernate对应的配置可以去掉了。

    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <!-- <property name="configLocation" value="classpath:hibernate.cfg.xml"></property> -->
        <!-- 注入一个DataSource -->
        <property name="dataSource" ref="dataSource"></property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
                <prop key="hibernate.hbm2ddl.auto">false</prop>
                <prop key="hibernate.show_sql">true</prop>
            </props>
        </property>
        <property name="mappingResources">
            <list>
                <value>model/user.hbm.xml</value>
            </list>
        </property>
    </bean>

　　　　然后配置sessionFactory，注入dataSource，里面的key配置了数据库方言和hibernate的其他配置，配完之后可以去掉hibernate配置文件相应的地方了，list里配置了mapping，把映射表也配上了，所以hibernate的配置文件完全没用了。

    <bean id="userDaoImpl" class="dao.userDaoImpl">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>

　　　　最后在dao中注入sessionFactory，这样就可以使用getHibernateTemplate这个方法了，少了很多代码。

　　　　userDao.java

package dao;

import java.util.List;

import model.user;

public interface userDao {
	public void save(user user);
	public void delete(user user);
	public void update(user user);
	public List<user> select();
}

　　　　userDaoImpl.java

package dao;

import java.util.List;

import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

import model.user;

public class userDaoImpl extends HibernateDaoSupport implements userDao{

	@Override
	public void save(user user) {
		// TODO Auto-generated method stub
		this.getHibernateTemplate().save(user);

	}

	@Override
	public void delete(user user) {
		// TODO Auto-generated method stub
		String hql = "delete from user where username = "+user.getUsername();
		this.getHibernateTemplate().bulkUpdate(hql);
	}

	@Override
	public void update(user user) {
		// TODO Auto-generated method stub
		this.getHibernateTemplate().update(user);

	}

	@Override
	public List<user> select() {
		// TODO Auto-generated method stub
		String hql = "from user";
		List<user> list = (List<model.user>) this.getHibernateTemplate().find(hql);
		return list;
	}

}

　　　　UserService.java

package service;

import java.util.List;

import dao.userDaoImpl;
import model.user;

public class UserService {
	private userDaoImpl userDaoImpl;

	public userDaoImpl getUserDaoImpl() {
		return userDaoImpl;
	}
	public void setUserDaoImpl(userDaoImpl userdao) {
		this.userDaoImpl = userdao;
	}
	//服务
	public void addService(user u){
		userDaoImpl.save(u);
	}
	public void updateService(user u){
		userDaoImpl.update(u);
	}
	public void deleteService(user u){
		userDaoImpl.delete(u);
	}
	public List<user> selectAllService(){
		return userDaoImpl.select();
	}

}

　　　　控制器

package action;

import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;

import model.user;
import service.UserService;

public class addUserAction extends ActionSupport implements ModelDriven<user>{
	private user u;
	private UserService userService;
	public UserService getUserService() {
		return userService;
	}

	public void setUserService(UserService usService) {
		this.userService = usService;
	}

	public user getU() {
		return u;
	}

	public void setU(user u) {
		this.u = u;
	}

	@Override
	public user getModel() {
		if(u == null)
		// TODO Auto-generated method stub
			u = new user();
		return u;
	}
	public String execute(){
		this.userService.addService(u);
		return SUCCESS;
	}
}

　　

package action;

import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;

import model.user;
import service.UserService;

public class deleteAction extends ActionSupport implements ModelDriven<user>{
	private user u;
	private UserService userService;
	public UserService getUserService() {
		return userService;
	}

	public void setUserService(UserService usService) {
		this.userService = usService;
	}

	public user getU() {
		return u;
	}

	public void setU(user u) {
		this.u = u;
	}

	@Override
	public user getModel() {
		if(u == null)
		// TODO Auto-generated method stub
			u = new user();
		return u;
	}
	public String execute(){
		this.userService.deleteService(u);
		return SUCCESS;
	}
}

　　　　页面代码

<%@ 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">
<%@taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>添加用户</title>
</head>
<body>
	<form action="add">
		<table>
			<tr>
				<td>用户名：</td>
				<td><input type="text" size="18" name="username"></td>
			</tr>
			<tr>
				<td>密码：</td>
				<td><input type="password" size="18" name="password"></td>
			</tr>
		</table>
		<s:submit value="提交"></s:submit>
		<s:reset value="重置"></s:reset>
	</form>
</body>
</html>

　　

<%@ 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">
<%@taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>删除用户</title>
</head>
<body>
	<form action="delete">
		<table>
			<tr>
				<td>用户名：</td>
				<td><input type="text" size="18" name="username"></td>
			</tr>
			<tr>
				<td>密码：</td>
				<td><input type="password" size="18" name="password"></td>
			</tr>
		</table>
		<s:submit value="提交"></s:submit>
		<s:reset value="重置"></s:reset>
	</form>
</body>
</html>

• 错误

　　　　首先遇到的异常非常多，我甚至有些怀疑（厌烦）spring框架的加入。

　　　　1.命名注入对象的时候要按照驼峰命名法。

　　　　2.莫名其妙无法打开数据库的链接，重新写配置文件不适用properties之后正常了。

org.springframework.dao.DataAccessResourceFailureException: Cannot open connection; nested exception is org.hibernate.exception.JDBCConnectionException: Cannot open connection 	at org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAcce

java.lang.NumberFormatException: For input string

　　　　3.struts配置action的时候不能不配置result，跳一堆红字...

　　　　4.在使用映射的时候，没有主键的时候会出错(或者我没找到合适的方式用)。如下错误：

ids for this class must be manually assigned before calling save(): model.user; nested exception is org.hibernate.id.IdentifierGenerationException: ids for this class must be manually assigned before calling save(): model.user

　　　　5.仔细写配置文件，超坑。类似如下：

Invalid property 'userService' of bean class [action.addUserAction]: Bean property 'userService' is not writable or has an invalid setter method. Did you mean 'usService'?

　　　　6.tomcat经常添乱，因为启动记录里面的项目关闭了或者删除了。最后我把服务器删了重新添加，受够了启动无限报错。

java.lang.IllegalArgumentException: Document base

　　　　7.仔细写好路径，web.xml的，不然有如下错误。

parsing XML document from ServletContext resource [/WEB-INF/applicationContext.xml]; nested exception is java.io.FileNotFoundException: Could not open ServletContext resource [/WEB-INF/applicationContext.xml]

• 最后

　　　　仍然很欣慰能运行正常，添加了spring之后设计变得简洁很多（非常仔细地写），如果使用了AOP则可以在不改写原有代码的情况下增加功能。