idea下spring+spring mvc+mybatis+mysql+maven框架搭建
写在前面
最近在学习ssm框架，因为不知名的原因，一个小小的框架竟然花了我四五天的时间，期间遇到了近百个各种各样的错误，也正是由于这些错误，让我对ssm框架有了进一步的认识，谨作略记，希望利于他人，仅供和我一样刚入门的新手参考，一起学习。理论的东西就不多少了，直接上配置吧。
创建项目：
这个就不多说了，直接百度，各种博客有很多，写得都很详细，但是要注意版本的问题，我怀疑之前我遇到的各种问题都和引入的spring之类的版本冲突有关，最好找发布时间不长的教程。
目录结构：
先看看整个项目的目录吧，目录结构如下图：
需要注意的就是：创建出来之后，目录结构里的main>java，test>java，test>resources都需要自己创建，可以直接在相应的文件夹上右键创建，也可以在file>project structure下创建，创建完directory之后需要右键mark as相应的文件夹。
还有就是会遇到在src>main>java下创建同级包的时候会默认合并路径，无法在一个包下创建同级包，按下图操作，取消勾选Hide Empty Middle Packages即可。
引入maven依赖
引入maven依赖需要注意的就是版本的统一管理，相关的包引入的版本最好能一致，保证兼容，将版本写在<properties></properties>里，然后再统一引用，既方便管理，又能避免很多问题，有点封装的意思。我折腾了很久很可能就是版本是随便选择的，所以导致各种问题。引入的依赖如下：
<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>demon</groupId>
<artifactId>demon</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>demon Maven Webapp</name>
<url>http://maven.apache.org</url>
<properties>
<spring.version>4.0.2.RELEASE</spring.version>
<mybatis.version>3.2.6</mybatis.version>
<slf4j.version>1.7.7</slf4j.version>
<log4j.version>1.2.17</log4j.version>
</properties>
<dependencies>
<!--junit单元测试-->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<!--spring相关的包-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</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-oxm</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-jdbc</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-aop</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
</dependency>
<!--mybatis相关的包-->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>${mybatis.version}</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.2.3</version>
</dependency>
<!--java ee-->
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>7.0</version>
</dependency>
<!--mysql-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.39</version>
</dependency>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.2.2</version>
</dependency>
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<!--日志管理的包-->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${log4j.version}</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.1.41</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${slf4j.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>${slf4j.version}</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.9.13</version>
</dependency>
<!--文件上传组件-->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.4</version>
</dependency>
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.9</version>
</dependency>
<dependency>
<groupId>com.esotericsoftware.reflectasm</groupId>
<artifactId>reflectasm</artifactId>
<version>1.09</version>
</dependency>
<!--hibernate验证框架-->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.2.4.Final</version>
</dependency>
</dependencies>
<build>
<finalName>demon</finalName>
<resources>
<resource>
<directory>src/main/java</directory>
<includes>
<include>**/*.xml</include>
</includes>
</resource>
<resource>
<directory>src/main/resources</directory>
<includes>
<include>*.xml</include>
<include>*.properties</include>
</includes>
</resource>
</resources>
</build>
</project>以上就是maven依赖的包，<build></build>标签里的内容是将resources目录和java目录下的文件也加到项目路径，因为我启动项目出现了mapper.xml，spring-mvc.xml文件无法加载的情况。
数据库建表：
create table `test`.`user`( `username` varchar(25) NOT NULL COMMENT `用户名`， `password` varchar(25) NOT NULL COMMENT `密码`， PRIMARYKEY(`username`) )ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT `用户信息表`;
创建pojo文件：
在po包下创建UserPo.java文件，记得加上构造方法，以及默认的构造方法，代码如下：
package com.demon.user.po;
/**
* @author zhulongkun20@163.com
* @date 2018/3/21 14:22
*/
public class UserPo {
private String username;
private String password;
public UserPo(String username, String password) {
this.username = username;
this.password = password;
}
public UserPo() {
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String toString() {
return "===== UserPo : [ username : " + username + ", password : " + password + " ] =====";
}
}创建UserDao接口：
创建UserDao.java接口，是接口，不是类！放与数据库操作相关的方法：
package com.demon.user.dao;
import com.demon.user.po.UserPo;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;
/**
* @author zhulongkun20@163.com
* @date 2018/3/21 14:23
*/
@Repository
public interface UserDao {
UserPo selectUserByUsername(@Param("username") String username);
}记得给接口加上@Repository注解。
创建UserService接口：
创建UserService.java，这个也是接口，不是方法，里面放与业务逻辑。
package com.demon.user.service;
import com.demon.user.po.UserPo;
/**
* @author zhulongkun20@163.com
* @date 2018/3/21 14:26
*/
public interface UserService {
public UserPo selectUserByUsername(String username);
}创建UserServiceImpl类，实现UserService接口：
创建UserServiceImpl类，实现UserService接口，记得加上@Service注解，不然spring配置文件不能创建bean。
package com.demon.user.service;
import com.demon.user.dao.UserDao;
import com.demon.user.po.UserPo;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
/**
* @author zhulongkun20@163.com
* @date 2018/3/21 14:27
*/
@Service
public class UserSeviceImpl implements UserService {
@Resource
private UserDao userDao;
public UserPo selectUserByUsername(String username) {
return userDao.selectUserByUsername(username);
}
}创建Controller.java文件：
记得给类加上@Controller注解，还有@RequestMapping("")注解，不然会报错，找不到controller。
package com.demon.user.controller;
import com.demon.user.po.UserPo;
import com.demon.user.service.UserService;
import org.apache.log4j.Logger;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
/**
* @author zhulongkun20@163.com
* @date 2018/3/21 15:34
*/
@Controller
@RequestMapping("/user")
public class UserController {
private static Logger logger = Logger.getLogger(UserController.class);
@Resource
private UserService userService;
@RequestMapping("/showUser.do")
public ModelAndView showUser(HttpServletRequest request) {
String username = request.getParameter("username");
UserPo userPo = userService.selectUserByUsername(username);
if (userPo != null) {
logger.info("====== request success.");
request.setAttribute("username", username);
return new ModelAndView("success", "message", username);
} else {
logger.info("====== request failed.");
return new ModelAndView("failed", "message",
"request failed, try again!");
}
}
}创建mybatis-user.xml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" >
<mapper namespace="com.demon.user.dao.UserDao">
<resultMap id="BaseResultMap" type="com.demon.user.po.UserPo">
<result column="username" property="username" jdbcType="VARCHAR"/>
<result column="password" property="password" jdbcType="VARCHAR"/>
</resultMap>
<select id="selectUserByUsername" resultMap="BaseResultMap" parameterType="java.lang.String">
SELECT
username,
password
FROM user
WHERE username = #{username, jdbcType=VARCHAR}
</select>
</mapper>注意命名空间namespace的指向的包。
日志管理：
在src>main>resources下创建log4j.properties文件，主要是log4j的配置，记得创建一个存放日志的file，更改日志输出的目标文件。
# 配置
log4j.rootLogger=debug,stdout,D,E
### 输出信息到控制抬 ###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=[%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n
### 输出DEBUG 级别以上的日志到文件F://logs/debug.log ###
log4j.appender.D=org.apache.log4j.FileAppender
log4j.appender.D.File=F:/coquetry-demon/logs/debug.log
log4j.appender.D.Append=true
log4j.appender.D.Threshold=DEBUG
log4j.appender.D.layout=org.apache.log4j.PatternLayout
log4j.appender.D.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%n
### 输出ERROR 级别以上的日志到文件F://logs/error.log ###
log4j.appender.E=org.apache.log4j.FileAppender
log4j.appender.E.File=F:/coquetry-demon/logs/error.log
log4j.appender.E.Append=true
log4j.appender.E.Threshold=ERROR
log4j.appender.E.layout=org.apache.log4j.PatternLayout
log4j.appender.E.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%数据库属性文件：
将数据库的用户名，密码等单独放到jdbc.properties文件中，方便项目的移植和管理。
database.driver=com.mysql.jdbc.Driver database.url=jdbc:mysql://localhost:3306/你的数据库名 database.username=你的数据库用户名 database.password=你的数据库密码
整合spring-mybatis：
创建spring-mybatis.xml配置文件：
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd">
<context:component-scan base-package="com.demon.user"/>
<context:property-placeholder location="classpath:/jdbc.properties"/>
<!--connect to database-->
<bean id="jdbcDataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${database.driver}"/>
<property name="url" value="${database.url}"/>
<property name="username" value="${database.username}"/>
<property name="password" value="${database.password}"/>
</bean>
<!--spring and mybatis configuration here-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="jdbcDataSource"/>
<property name="mapperLocations" value="classpath:com/demon/user/mapper/*.xml"/>
</bean>
<!--the package name where contains dao, enable auto scan-->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.demon.user.dao"/>
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
</bean>
<!--transaction manager-->
<!--
<tx:annotation-driven transaction-manager="transactionManager"/>
-->
<!--add transaction operation-->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="jdbcDataSource"/>
</bean>
</beans>配置spring-mvc：
创建spring-mvc.xml文件，配置spring mvc：
<?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-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">
<context:component-scan base-package="com.demon.user.controller"/>
<mvc:annotation-driven/>
<bean id="mappingJacksonHttpMessageConverter"
class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
<property name="supportedMediaTypes">
<list>
<value>text/html;charset=UTF-8</value>
</list>
</property>
</bean>
<!-- 启动SpringMVC的注解功能，完成请求和注解POJO的映射 -->
<bean
class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<ref bean="mappingJacksonHttpMessageConverter"/> <!-- JSON转换器 -->
</list>
</property>
</bean>
<!-- 定义跳转的文件的前后缀 ，视图模式配置-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/>
</bean>
<!--使用默认的Servlet来响应静态文件-->
<mvc:default-servlet-handler/>
<!-- 配置文件上传，如果没有使用文件上传可以不用配置，当然如果不配，那么配置文件中也不必引入上传组件包 -->
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- 默认编码 -->
<property name="defaultEncoding" value="utf-8"/>
<!-- 文件大小最大值 -->
<property name="maxUploadSize" value="10485760000"/>
<!-- 内存中的最大值 -->
<property name="maxInMemorySize" value="40960"/>
</bean>
</beans>配置web.xml：
这个就是要注意<servlet-mapping></servlet-mapping>拦截器的配置，这里会产生很多错误。
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<session-config>
<session-timeout>60</session-timeout>
</session-config>
<filter>
<filter-name>encode</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>encode</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>classpath:log4j.properties</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mybatis.xml</param-value>
</context-param>
<!-- Spring监听器 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- 防止Spring内存溢出监听器 -->
<listener>
<listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>
</listener>
<!--RequestContextListener将Spring容器与Web容器结合的更加密切。这是可选配置-->
<listener>
<listener-class>
org.springframework.web.context.request.RequestContextListener
</listener-class>
</listener>
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<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>springmvc</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
</web-app>到这里三大框架整合完毕了，主要是配置文件容易出错。
mybatis测试：
在test>java下建一个包，然后建立一个MybatisTest.java的测试类，测试一下能不能从数据库里读出信息。
package com.demon.test;
import com.demon.user.po.UserPo;
import com.demon.user.service.UserService;
import org.apache.log4j.Logger;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import javax.annotation.Resource;
/**
* @author zhulongkun20@163.com
* @date 2018/3/21 15:00
*/
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:spring-mvc.xml", "classpath:spring-mybatis.xml"})
public class MybatisTest {
private static Logger logger = Logger.getLogger(MybatisTest.class);
@Resource
private UserService userService;
@Test
public void selectUserByUsernameTest() {
String username = "admin1";
UserPo userPo = userService.selectUserByUsername(username);
if (userPo != null) {
logger.info("======= Test Result =======\n");
logger.info(userPo.toString());
logger.info("======= Result End =======\n");
}
}
}如果能在日志里找到输出信息，那恭喜，mybatis没问题，如果有错，那就查日志，然后去各种百度吧，好事多磨，放平心态。。
jsp页面：
简单的测试页面：
index.jsp：
<%--
Created by IntelliJ IDEA.
User: zhulongkun
Date: 2018/3/21
Time: 13:25
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>欢迎访问</title>
</head>
<body>
<%
String path = request.getContextPath();
%>
<div align="center">
<form action="<%=path%>/user/showUser.do" method="post">
<p>欢迎你的访问, 请输入个人信息</p>
<hr/>
<p>
<label>
<input type="text" name="username" width="300px" height="45px"/>
</label>
</p>
<p>
<input type="submit" value="提交" width="100px" height="45px"/></p>
</form>
</div>
</body>
</html>请求成功则跳转到success.jsp：
<%@ page import="com.demon.user.po.UserPo" %><%--
Created by IntelliJ IDEA.
User: zhulongkun
Date: 2018/3/21
Time: 15:44
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>request success</title>
</head>
<body>
<%
String username = (String) request.getAttribute("username");
%>
<div align="center">
<p>
<h1>welcome <%=username%> !</h1
</div>
</body>
</html>如果请求失败，则跳转到failed.jsp：
<%--
Created by IntelliJ IDEA.
User: zhulongkun
Date: 2018/3/21
Time: 15:45
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>request failed</title>
</head>
<body>
<div align="center">
<h1>request failed, try again, please.</h1>
</div>
</body>
</html>看似简单，却折腾了几天，很多次感到绝望，但是不修bug，人生还有什么意义？要不断的找原因，不断地改错，才能不断地进步，也算是一点心得吧！
以上です！
