SSM(Spring+Spring MVC+Mybatis)框架整合过程

最近做一个项目用到了SSM框架，在此记录一下。本人萌新，错误之处，欢迎大家交流指正。

这里将实现一个简单的登录功能。

一、代码结构

为了方便管理，这里使用Maven来管理整个项目。代码结构如下图所示：

entity定义各种实体类。

dao数据接入，定义各种操作数据库的接口。

mapper存放mybatis数据库映射配置。

service业务层，定义各种业务接口。

serviceImpl对业务层接口的实现。

controller控制层，用于对业务模块的流程控制。

二、Mybatis与Spring的整合

1、pom.xml配置

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>cn.ipoc</groupId>
  <artifactId>ssmtest</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>Maven Webapp Archetype</name>
  <url>http://maven.apache.org</url>
  
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <spring.version>4.1.4.RELEASE</spring.version>
    <jackson.version>2.5.0</jackson.version>
  </properties>
  
  <dependencies>
  
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    
    <!-- spring配置 -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-beans</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>${spring.version}</version>
      <scope>test</scope>
    </dependency>
    
    <!-- mybatis 包 -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.2.8</version>
    </dependency>

    <!--mybatis spring 插件 -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.2.2</version>
    </dependency>

    <!-- mysql连接 -->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.44</version>
    </dependency>
    
    <!-- 数据源 -->
    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5-pre8</version>
    </dependency>

    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjweaver</artifactId>
      <version>1.8.4</version>
    </dependency>
    
    <!-- servlet -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>servlet-api</artifactId>
      <version>3.0-alpha-1</version>
    </dependency>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>
    
  </dependencies>
  <build>
    <finalName>ssmtest</finalName>
    <plugins>  
        <!-- define the project compile level -->  
        <plugin>  
            <groupId>org.apache.maven.plugins</groupId>  
            <artifactId>maven-compiler-plugin</artifactId>  
            <version>2.3.2</version>  
            <configuration>  
                <source>1.8</source>  
                <target>1.8</target>  
            </configuration>  
        </plugin>  
    </plugins>  
  </build>
</project>

2、web.xml配置

<web-app xmlns="http://java.sun.com/xml/ns/javaee"  
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee   
                        http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"  
                        version="3.0">  
    <!-- <display-name>Archetype Created Web Application</display-name> -->  
    
    <!-- Spring配置 -->
    <!-- 配置Spring配置文件路径，让ContextLoaderListener进行解析 -->  
    <context-param>
    	<param-name>contextConfigLocation</param-name>
    	<param-value>classpath:applicationContext.xml</param-value>
    </context-param>
    
   	<!-- 配置Spring上下文监听器，再启动WEB容器时，
   	              自动装载applicationContext.xml配置 -->
   	<listener>
   		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
   	</listener>
   	
   	<!-- 配置Spring字符编码过滤器 -->
   	<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>
   		<init-param>
   			<param-name>forceEncoding</param-name>
   			<param-value>true</param-value>
   		</init-param>
   	</filter>
   	<filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>  

3、applicationContext配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       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-4.1.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context.xsd">
      
      <!-- 引入jdbc配置 -->
      <context:property-placeholder location="classpath:jdbc.properties"/>
      
      <!-- 扫描文件-->
      <context:component-scan base-package="cn.ipoc"/>

      <!--配置数据源-->
      <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
	      <property name="driverClass" value="${jdbc_driverClassName}"/>
	      <property name="jdbcUrl" value="${jdbc_url}"/>
	      <property name="user" value="${jdbc_username}"/>
	      <property name="password" value="${jdbc_password}"/>
	      <!--连接池中保存的最大连接数目-->
	      <property name="maxPoolSize" value="${maxPoolSize}"/>
	      <!--连接池中保存的最少连接数目-->
	      <property name="minPoolSize" value="${minPoolSize}"/>
	      <!-- 初始化连接大小 -->
	      <property name="initialPoolSize" value="${initialPoolSize}"/>
	      <!-- 获取连接最大等待时间 -->
	      <property name="maxConnectionAge" value="${maxConnectionAge}"/>
	      <!-- 连接池最大空闲 -->
	      <property name="maxIdleTime" value="${maxIdleTime}"/>
      </bean>
     	
      <!--配置sqlSessionFactory 并将数据源注入-->
      <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
	      <!--注入数据源-->
	      <property name="dataSource" ref="dataSource"/>
	      <!--指定要使用到的mybatis配置文件-->
	      <property name="configLocation" value="classpath:mybatis-config.xml"/>
	      <!--用于配置mapper映射xml-->
	      <property name="mapperLocations" value="classpath*:cn/ipoc/mapper/*.xml"/>
      </bean>
      
      <!-- 创建数据映射器-->
      <bean  class="org.mybatis.spring.mapper.MapperScannerConfigurer">
          <property name="basePackage" value="cn.ipoc.dao"/>
          <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>  
      </bean>
      <!-- 对数据源进行事务管理 -->
      <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
      	  <property name="dataSource" ref="dataSource"/>
      </bean>
      
</beans>

4、jdbc.properties配置

jdbc.properties保存数据库相关信息，需要根据数据库配置进行修改。

jdbc_driverClassName=com.mysql.jdbc.Driver
jdbc_url=jdbc:mysql://localhost:3306/test_my?characterEncoding=utf8
jdbc_username=root
jdbc_password=123456
maxPoolSize=20
minPoolSize=2
initialPoolSize=2
maxConnectionAge=6000
maxIdleTime=60

5、mybatis-config配置

为了方便后续编程，在mybatis的配置文件中为实体类设置简短别名。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>

    <!--为cn.ipoc.entity.User 设置别名 User 方便调用-->
    <typeAliases>
        <typeAlias alias="User" type="cn.ipoc.entity.User"/>
    </typeAliases>
   
</configuration>

配置完成后，可以开始设计相关数据库表结构。

6、User类

现在开始实现entity下的User类。

package cn.ipoc.entity;

public class User {
	private String uid;
	private String password;
	
	public User() {
		super();
	}
	
	//初始化构造函数
	public User(String uid,String password) {
		this.uid=uid;
		this.password=password;
	}
	
	public String getUid() {
		return uid;
	}
	public void setUid(String uid) {
		this.uid=uid;
	}
	
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password=password;
	}
}

7、dao接口

在"cn.ipoc.dao"中定义UserDao接口。

package cn.ipoc.dao;

import cn.ipoc.entity.User;

public interface UserDao {
	public User selectById(String uid);
}

8、映射文件

在"cn.ipoc.mapper"中配置mybatis映射文件。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

 <!--namespace用于与DAO层的接口类进行绑定,这样我们无需实现DAO层的接口
  类,其接口类就能够自动的找到相关的SQL语句进行绑定实现-->

<mapper namespace="cn.ipoc.dao.UserDao">
    <!--select表示查询,它的id名称必须与DAO层接口的方法名相同,否则无法绑定-->    
    <select id="selectById" parameterType="String" resultType="User">
        select * from user where uid = #{id}
    </select>
</mapper>

9、测试

至此，Mybatis与Spring整合的相关配置已基本完成。下面在"cn.ipoc.test"下定义一个test类来测试整合是否成功。

package cn.ipoc.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import cn.ipoc.dao.UserDao;
import cn.ipoc.entity.User;

public class test {
	private static ApplicationContext ac;
	static {
	         ac = new ClassPathXmlApplicationContext("applicationContext.xml");
	}
	public static void main(String[] args) {
		
		UserDao mapper = (UserDao) ac.getBean("userDao");
		User user = mapper.selectById("user001");
		System.out.println("user="+user.getUid()+"\n"+"password="+user.getPassword());
	}
}

如果整合成功，控制台会输出如下信息：

三、Mybatis与Spring MVC整合

在完成Mybatis和Spring的整合后，接下来开始Mybatis与Spring MVC的整合。

首先在web.xml中配置Spring MVC的前端控制器DispatcherServlet。

1、web.xml

<!-- springMVC 核心控制器  DispatcherServlet 配置 -->
    <servlet>
    	<servlet-name>dispatcher</servlet-name>
    	<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    	<init-param>
    		<!-- 标明springmvc配置位置 -->
    		<param-name>contextConfigLocation</param-name>
    		<param-value>classpath:spring-mvc.xml</param-value>
    	</init-param>
    	<load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
    	<servlet-name>dispatcher</servlet-name>
    	<!-- 拦截所有*.do 的请求,交给DispatcherServlet处理,性能最好 -->
        <url-pattern>*.do</url-pattern>
    </servlet-mapping>
    
    <!-- 设定默认的首页 -->
    <welcome-file-list>
    	<welcome-file>login.jsp</welcome-file>
    </welcome-file-list>

2、spring-mvc.xml

接下来在spring-mvc.xml中配置Spring MVC的框架，存放在"src/main/resources"下。

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc" 
       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-4.1.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context.xsd
      http://www.springframework.org/schema/mvc
      http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd">
	
	<!-- 配置扫描控制器， Spring自动到 cn.ipoc.controller下
	              扫描带有@controller @service @component等注解等类，将他们自动实例化-->
	<context:component-scan base-package="cn.ipoc" />
	
	<!--<mvc:annotation-driven /> 会自动注册DefaultAnnotationHandlerMapping与
	     AnnotationMethodHandlerAdapter 两个bean,它解决了一些 @controller 注解使用时的提前配置-->
    <mvc:annotation-driven />
	
	<!-- 配置页面控制器 -->
	<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/"/>
		<property name="suffix" value=".jsp" /> 
    </bean>
    
</beans>

3、业务实现

在"cn.ipoc.service"中编写接口类UserService。

package cn.ipoc.service;

public interface UserService {
	public int login(String username,String password);
}

接下来，在"cn.ipoc.serviceImpl"中编写UserServiceImpl类实现UserService中的login方法。

package cn.ipoc.serviceIpml;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import cn.ipoc.dao.UserDao;
import cn.ipoc.entity.User;
import cn.ipoc.service.UserService;

@Service("UserService")
public class UserServiceImpl implements UserService{

	//自动注入userdao 用于访问数据库
	@Autowired
	UserDao userDao;

	public int login(String username, String password) {
		// TODO Auto-generated method stub
		User user=userDao.selectById(username);
		if(null!=user) {
			if(user.getUid().equals(username)&&user.getPassword().equals(password)) {
				return 0; //登录成功
			}else {
				return 1; //用户名或密码错误
			}
		}else {
			return 2;     //用户不存在
		}
	}
}

4、控制层实现

在"cn.ipoc.controller"中实现LoginCtrl类，用于处理前端提交的业务。

package cn.ipoc.controller;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import cn.ipoc.service.UserService;

//@Controller 注解表示本类为web层控制组件
@Controller
//@RequestMapping("/user") 用于标定访问时对url位置
@RequestMapping("/user")
@Scope("prototype")
public class LoginCtrl {
	//自动注入业务层的UserService类
	@Autowired
	UserService userService;
	
	//login业务的访问位置为  /user/login
	@RequestMapping("/login")
	public String login(HttpServletRequest request) 
			throws ServletException, IOException{
		String username = request.getParameter("username");
		String password = request.getParameter("password");
		int loginStatus = userService.login(username, password);
		if(loginStatus==0) {
			request.setAttribute("msg", "登录成功");
		}else if(loginStatus==1) {
			request.setAttribute("msg", "用户名或密码错误");
		}else {
			request.setAttribute("msg", "用户不存在");
		}
		return "status";
	}
}

5、jsp实现

login.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<html>
<head>
    <title></title>
</head>
<body>
<form name="form" action="<%=basePath %>user/login.do" method="post" >
  <table width="300" border="1" align="center">
  <tr>
    <td colspan="2">登入窗口</td>
  </tr>
  <tr>
      <td>用户名:</td>
      <td><input type="text" name="username">
      </td>
  </tr>
  <tr>
      <td>密码:</td>
      <td><input  type="password" name="password"/>
      </td>
  </tr>
  <tr>
    <td colspan="2">
      <input type="submit" name="submit" value="登录"/>
    </td>
  </tr>
  </table>
</form>
</body>
</html>

status.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<html>
<head>
    <title></title>
</head>
<body>
<br>
${msg}
<br>

</body>
</html>

至此，所有的整合工作已完成。看一下整合结果吧。

登录界面

登录成功

登录失败