使用maven构建一个SSM（Spring+SpringMVC+Mybatis(阿里数据连接池）的简单环境

首先依次简单介绍一下maven SSM

maven:一个主要用来管理项目之间Jar包依赖关系

Sping:轻型的框架容器（控制反转Ioc面向切面AOP）

SpringMVC:减少控制器与视图和模型层的耦合,更好的控制

Mybatis:原来叫ibatis,后入Google更名，是一个半自动的Java持久层框架，利用xml配置或注解的方式执行命令，整合了大量的JDBC代码和原是配置，感觉xml配置也是实现了sql语句和Java的分离，为更好的优化sql奠定了良好的基础

Druid:阿里的数据库连接池，功能全面，性能比较优越，主要用来管理连接资源

整个项目的结构





整个代码结构就是这样：

接下来利用maven导入必须的jar包：网址mvn仓库

Spring:

Spring-context Spring-webmvc Spring-orm)(可选Spring-test)用于测试的话记得导入Junit

Mybatis:mybatis

mybatis-spring:mybatis-spring

Mysql的JAR包

druid连接池

直接上pom.xml(有点乱)

<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/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion>
<groupId>com.mybatis</groupId>
<artifactId>web15</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
<spring-version>4.1.6.RELEASE</spring-version>
<mybatis-version>3.4.1</mybatis-version>

</properties>
<dependencies>

<!-- https://mvnrepository.com/artifact/junit/junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>

<!--
Spring核心包加载 -->
<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring-version}</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>4.1.6.RELEASE</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring-version}</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-test -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring-version}</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-context-support -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring-version}</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-tx -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring-version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-orm -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>4.1.6.RELEASE</version>
</dependency>

<!--
mybatis核心包加载 -->

<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>${mybatis-version}</version>
</dependency>

<!--   mybatisSpring核心包 -->
<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis-spring -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.0</version>
</dependency>

<!--
Mysql核心包 -->
<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.39</version>
</dependency>
<!-- Jstl -->

<!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.6</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.18</version>
</dependency>

</dependencies>
</project>

接下来配置web.xml，主要是服务器启动加载配置文件和路径的设置，关于Spring的xml加载方式可选择Servlet的init方法加载也可使用监听器，

（1）监听器配置

org.springframework.web.context.ContextLoaderListener

contextConfigLocation

classpath:路径

我的web.xml采用第二种方式直接上代码：

//直接加载config下的所有xml文件
<servlet>
<servlet-name>br</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:config/*.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
<servlet-name>br</servlet-name>
<url-pattern>*.do</url-pattern>

</servlet-mapping>
</web-app>

Springmvc配置注解驱动，扫描Controller包，配置视图解析器

代码：

`

<?xml version="1.0" encoding="UTF-8"?>
<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
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-4.1.xsd http://www.springframework.org/schema/tx http://www.springframework.or abd3
g/schema/tx/spring-tx-4.1.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd">

<context:component-scan base-package="com.ssh.service"></context:component-scan>
<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
<property name="url" value=""></property>
<property name="username" value=""></property>
<property name="password" value=""></property>
</bean>

<!--  spring与mybatis融合 -->

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean" >
<property name="dataSource" ref="dataSource"></property>
<property name="mapperLocations" value="classpath:com/ssh/dao/*.xml" />

</bean>

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.ssh.dao" />
</bean>

</beans>

mapper的文件，namespace是接口的全路径，id是方法名，

<?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">

<mapper namespace="com.ssh.dao.IUserDao">

<select id="getUsers"  resultType="com.ssh.pojo.User">
select username,password from user
</select>

</mapper>

`至此配置文件的一些基本设置就完成了，测试可以跑起来，后续可以按照需要设置连接池大小和事务管理，只需在spring-mybatis添加属性或bean,为了跟好的管理可以spring扫包分开

用户名和密码也可以通过EL表达式去取加密过后解密的导入的文件，就这样，手写一遍框架的基本搭建过程，加深理解，实践出真知。