基于Maven构建的Spring+Mybatis项目

项目的目录结构：

1.基于Maven构建Web项目

参考：基于Maven构建Web项目

2.导入项目依赖

Spring
核心容器（Beans、Core、Context、Context support、Expression）

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

面向切面编程（Aop、Aspects）

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

Web调用

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

因为spring-webmvc依赖于spring-web，所以在pom.xml中不需要显式导入spring-web。
数据访问

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

mybatis

<dependency>
	<groupId>org.mybatis</groupId>
	<artifactId>mybatis</artifactId>
	<version>3.4.6</version>
</dependency>
<dependency>
	<groupId>org.mybatis</groupId>
	<artifactId>mybatis-spring</artifactId>
	<version>1.3.2</version>
</dependency>

mysql

<dependency>
	<groupId>mysql</groupId>
	<artifactId>mysql-connector-java</artifactId>
	<version>5.1.38</version>
</dependency>

c3p0

<dependency>
	<groupId>com.mchange</groupId>
	<artifactId>c3p0</artifactId>
	<version>0.9.5.2</version>
</dependency>

JSTL

<dependency>
	<groupId>jstl</groupId>
	<artifactId>jstl</artifactId>
	<version>1.2</version>
</dependency>
<dependency>
	<groupId>taglibs</groupId>
	<artifactId>standard</artifactId>
	<version>1.1.2</version>
</dependency>

最终Maven依赖的包如下图所示：

3. 编写配置文件

部署描述符web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>spring5_mybatis3</display-name>
  <!-- needed for ContextLoaderListener -->
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>classpath:applicationContext.xml</param-value>
	</context-param>

	<!-- Bootstraps the root web application context before servlet initialization -->
	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>
	
	<filter>
		<filter-name>CharacterEncodingFilter</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>CharacterEncodingFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
	<filter>
		<filter-name>HiddenHttpMethodFilter</filter-name>
		<filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
	</filter>
	
	<filter-mapping>
		<filter-name>HiddenHttpMethodFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
  
  <!-- The front controller of this Spring Web application, responsible for handling all application requests -->
	<servlet>
		<servlet-name>springDispatcherServlet</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:springmvc.xml</param-value>
		</init-param>
		<load-on-startup>1</load-on-startup>
	</servlet>

	<!-- Map all requests to the DispatcherServlet for handling -->
	<servlet-mapping>
		<servlet-name>springDispatcherServlet</servlet-name>
		<url-pattern>/</url-pattern>
	</servlet-mapping>
</web-app>

Spring的配置文件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"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:mybatis-spring="http://mybatis.org/schema/mybatis-spring"
	xsi:schemaLocation="http://mybatis.org/schema/mybatis-spring http://mybatis.org/schema/mybatis-spring-1.2.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

	<context:component-scan base-package="com.mybatis">
		<context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
	</context:component-scan>
	
	<context:property-placeholder location="classpath:dbconfig.properties"/>
	
	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
		<property name="jdbcUrl" value="${jdbc.url}"></property>
		<property name="driverClass" value="${jdbc.driver}"></property>
		<property name="user" value="${jdbc.username}"></property>
		<property name="password" value="${jdbc.password}"></property>
	</bean>
	
	<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
		<property name="dataSource" ref="dataSource"></property>
	</bean>
	
	<tx:annotation-driven transaction-manager="transactionManager"/>
	
	<!-- 整合mybatis -->
	<bean id="sqlSessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
		<property name="dataSource" ref="dataSource"></property>
		<property name="configLocation" value="classpath:mybatis-config.xml"></property>
		<property name="mapperLocations" value="classpath:mybatis/mapper/*.xml"></property>
	</bean>
	
	<mybatis-spring:scan base-package="com.mybatis.dao"/>
	
</beans>

dbconfig.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis?useSSL=false
jdbc.username=root
jdbc.password=root

Spring MVC的配置文件springmvc.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"
	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.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.xsd">

	<context:component-scan base-package="com.mybatis" use-default-filters="false">
		<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
	</context:component-scan>
	
	<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/views/"></property>
		<property name="suffix" value=".jsp"></property>
	</bean>
	
	<mvc:annotation-driven></mvc:annotation-driven>
	<mvc:default-servlet-handler/>
</beans>

Mybatis的配置文件mybatis-config.xml

<?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>
	<settings>
		<setting name="mapUnderscoreToCamelCase" value="true"/>
		<setting name="lazyLoadingEnabled" value="true"/>
		<setting name="aggressiveLazyLoading" value="false"/>
		<!-- 打印查询语句 -->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
	</settings>
</configuration>

loj4j.properties

#定义LOG输出级别  
log4j.rootLogger=DEBUG,INFO,Console,File  
#定义日志输出目的地为控制台  
log4j.appender.Console=org.apache.log4j.ConsoleAppender  
log4j.appender.Console.Target=System.out  
#可以灵活地指定日志输出格式，下面一行是指定具体的格式  
log4j.appender.Console.layout = org.apache.log4j.PatternLayout  
log4j.appender.Console.layout.ConversionPattern = [%p] [%d{yyyy-MM-dd HH:mm:ss}][%c]%m  %l%n
 
#文件大小到达指定尺寸的时候产生一个新的文件  
log4j.appender.File = org.apache.log4j.RollingFileAppender  
#指定输出目录  
log4j.appender.File.File = logs/ssm.log  
#定义文件最大大小  
log4j.appender.File.MaxFileSize = 10MB  
#输出所以日志，如果换成DEBUG表示输出DEBUG以上级别日志  
log4j.appender.File.Threshold = ALL  
log4j.appender.File.layout = org.apache.log4j.PatternLayout  
log4j.appender.File.layout.ConversionPattern = [%p] [%d{yyyy-MM-dd HH:mm:ss}][%c]%m  %l%n
#mybatis日志配置 需要将日志的输出级别调为debug
log4j.logger.com.ibatis=DEBUG
log4j.logger.com.ibatis.common.jdbc.SimpleDataSource=DEBUG
log4j.logger.com.ibatis.common.jdbc.ScriptRunner=DEBUG
log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate=DEBUG
#与sql相关
log4j.logger.java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

两步实现在Eclipse中打印SQL语句

1. 在类路径下添加log4j.properties文件。
2. 在mybatis-config.xml中添加<setting name="logImpl" value="STDOUT_LOGGING"/>。

4. 编写源代码

实体类

public class Employee {
	private Integer id;
	private String lastName;
	private String email;
	private String gender;
	private Department dept;
	
	//setter and getter
	
}

public class Department {
	private Integer id;
	private String departmentName;
	private List<Employee> employees;
	
	//setter and getter
	
}

如果启用了mybatis的缓存，则实体类需要实现Serializable接口。
Mapper

package com.mybatis.dao;

import java.util.List;

import com.mybatis.bean.Employee;

public interface EmployeeMapper {
	
	public Employee getEmpById(Integer id);
	
	public List<Employee> getEmps();
}

<?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.mybatis.dao.EmployeeMapper">
	<!-- public Employee getEmpById(Integer id); -->
	<select id="getEmpById" resultType="com.mybatis.bean.Employee">
		select * from tb_employee where id=#{id}
	</select>
	
	<!--public List<Employee> getEmps();  -->
	<select id="getEmps" resultType="com.mybatis.bean.Employee">
		select * from tb_employee
	</select>
</mapper>

Service

package com.mybatis.service;

import java.util.List;

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

import com.mybatis.bean.Employee;
import com.mybatis.dao.EmployeeMapper;

@Service
public class EmployeeService {
	
	@Autowired
	private EmployeeMapper employeeMapper;
	
//	@Autowired
//	private SqlSession sqlSession;
	
	public List<Employee> getEmps(){
		//
		//EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class);
		return employeeMapper.getEmps();
	}

}

Controller

package com.mybatis.controller;

import java.util.List;
import java.util.Map;

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

import com.mybatis.bean.Employee;
import com.mybatis.service.EmployeeService;

@Controller
public class EmployeeController {
	
	@Autowired
	private EmployeeService employeeService;
	
	@RequestMapping("/getemps")
	public String emps(Map<String,Object> map){
		List<Employee> emps = employeeService.getEmps();
		map.put("allEmps", emps);
		return "list";
	}

}

JSP页面

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<html>
	<body>
		<a href="getemps">查询所有员工</a>
	</body>
</html>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>员工列表</title>
</head>
<body>
	<table>
		<tr>
			<td>id</td>
			<td>lastName</td>
			<td>email</td>
			<td>gender</td>
		</tr>
		<c:forEach items="${allEmps }" var="emp">
			<tr>
				<td>${emp.id }</td>
				<td>${emp.lastName }</td>
				<td>${emp.email }</td>
				<td>${emp.gender }</td>
			</tr>
		</c:forEach>
	</table>
</body>
</html>

启动项目之前，需要在MYSQL中新建数据库和表。

下载示例源码：https://pan.baidu.com/s/13LxspHlRydthVfvKb8-WaQ 提取码：2w2w

注：这篇随笔的目的在于熟悉使用Maven构建Spring整合MyBatis的Web项目的过程。