最近没事,个人试着玩,想搭建一个Spring+SpringMvc+Mybatis框架,用Maven来做项目管理。由于本人对Mybatis和Maven都不是很熟练,所以搭建起来特别费劲,所以写个帖子来总结一下搭建过程遇到的各种问题。
首先需要恶补一下Mybatis的原理,然后查阅了一下Mybatis和Spring融合的方式,主要有三种,可参考下面的链接,http://blog.youkuaiyun.com/bluesky5219/article/details/7066174
我选用的是第一种,用MapperFactoryBean,感觉用annotation来标注,更加利于团队合作,接下来着手搭建这个框架。
框架文件目录如下:
然后就是各种文件的配置了:
首先是Model类User,它和数据库中的tb_user表对应,主键为id,其他两个属性为username和password。代码如下:
public class User {
private int id;
private String name;
private String password;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
接下来就是DAO了,本框架的DAO如下所示,采用Annotation标注的形式。@Select中是对应的sql语句,下面是对应的接口函数名、参数、返回类型。
package com.springapp.dao;
import com.springapp.model.User;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.springframework.stereotype.Repository;
/**
* Created by lihaibo on 14-11-23.
*/
public interface UserDAO {
@Select("SELECT * FROM tb_user WHERE id = #{userId}")
User getUser(@Param("userId") int id);
}
接下来就是实现类UserDAOImpl,它注入了userDAO类,这个类是有MapperFactoryBean生产的,出入了两个参数,一个是mapperInterface,另一个是sqlSessionFactory,具体参照applicationContext配置文件。
package com.springapp.daoImpl;
import com.springapp.dao.UserDAO;
import com.springapp.model.User;
import org.mybatis.spring.mapper.MapperFactoryBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
/**
* Created by lihaibo on 14-11-23.
*/
@Service("userDAOImpl")
public class UserDAOImpl{
@Resource
private UserDAO userMapper;
public User getById(int id){
return userMapper.getUser(id);
}
}
接下来就是控制器了,本文的控制器是HelloController,它注入了实现类UserDAOImpl。接收到前台页面请求后返回相应的message信息。
package com.springapp.mvc;
import com.springapp.dao.UserDAO;
import com.springapp.daoImpl.UserDAOImpl;
import com.springapp.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import javax.annotation.Resource;
@Controller
@RequestMapping("/")
public class HelloController {
@Autowired
private UserDAOImpl userDAOImpl;
@RequestMapping(method = RequestMethod.GET)
public String printWelcome(ModelMap model) {
User user=userDAOImpl.getById(1);
model.addAttribute("message", user.getName()+user.getPassword());
return "hello";
}
}
前台页面很简单,如下所示:
<html>
<body>
<h1>${message}</h1>
</body>
</html>
说完主要的类,接下来说主要的配置文件。
首先是pom.xml配置文件,主要的问题是jar包的版本问题,我用的spring为3.2.0,mybatis为3.2.0,mybatis-spring为1.1.1。版本不同很容易有jar包冲突,这是我搭建过程中遇到最大的一个问题,需要多注意一点。
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.springapp</groupId>
<artifactId>TestSpringMvc</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>TestSpringMvc</name>
<properties>
<spring.version>3.2.0.RELEASE</spring.version>
<!-- mybatis版本号 -->
<mybatis.version>3.2.0</mybatis.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${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核心包 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>${mybatis.version}</version>
<exclusions>
<exclusion>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
</exclusion>
</exclusions>
</dependency>
<!-- mybatis/spring包 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.1.1</version>
<exclusions>
<exclusion>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
</exclusion>
<exclusion>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
</exclusion>
<exclusion>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.2.2</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.16</version>
</dependency>
<!-- mysql驱动包 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.29</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>3.0.5.RELEASE</version>
</dependency>
</dependencies>
<build>
<finalName>TestSpringMvc</finalName>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<includes>
<include>**/*Tests.java</include>
</includes>
</configuration>
</plugin>
</plugins>
</build>
</project>
接下来肯定是web.xml文件的配置了,主要配置spring监听器和servlet分发起,都默认读取WEB-INF下面的applicationContext.xml文件和mvc-dispatcher-servlet.xml文件。
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>Spring MVC Application</display-name>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
<servlet>
<servlet-name>mvc-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>mvc-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
家下来就是applicationContext.xml文件的配置数据源datasource、sqlSessionFactory和Mapper。数据源主要用于数据库连接,自建连接池。sqlSessionFactory生产sqlSession用来映射sql语句,mapper主要用来UserDAO,做数据库的映射。
<?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:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- 引入jdbc配置文件 -->
<context:property-placeholder location="/WEB-INF/resource/jdbc.properties" />
<!--创建jdbc数据源 -->
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName" value="${jdbc_driverClassName}" />
<property name="url" value="${jdbc_url}" />
<property name="username" value="${jdbc_username}" />
<property name="password" value="${jdbc_password}" />
<property name="maxActive" value="50" />
<property name="maxIdle" value="5" />
<property name="maxWait" value="5000" />
</bean>
<!-- (事务管理)transaction manager, use JtaTransactionManager for global tx -->
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />
</bean>
<!-- 可通过注解控制事务 -->
<tx:annotation-driven />
<!-- 创建SqlSessionFactory,同时指定数据源 -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
</bean>
<!--创建数据映射器,数据映射器必须为接口-->
<bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
<property name="mapperInterface" value="com.springapp.dao.UserDAO" />
<property name="sqlSessionFactory" ref="sqlSessionFactory" />
</bean>
</beans>
接下来是mvc-dispatcher-servlet.xml配置文件了,
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 激活@Controller模式 -->
<mvc:annotation-driven />
<context:component-scan base-package="com.springapp"/>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/pages/"/>
<property name="suffix" value=".jsp"/>
</bean>
</beans>
最后就是用于jdbc连接的数据库配置文件jdbc.properties文件:
jdbc_driverClassName=com.mysql.jdbc.Driver
jdbc_url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8
jdbc_username=root
jdbc_password=root
工程的所有代码都贴完了,最后就是数据库了,数据库就不贴了,就是一个tb_user表,然后一个id主键,username、password字段。
搭建过程遇到的主要problem:
我觉得我遇到的主要最大问题是版本的问题。我使用idea开发工具,一键搭建springMvc的,中间主要遇到的问题是spring和jdk版本兼容问题,我刚开始用的是jdk8,和spring3.2.0不兼容,后来换成jdk7了。然后最大的问题是spring、mybatis和mybatis-spring三个jar包的版本问题,具体版本参照上面代码,给大家的建议是搭建框架之前一定要看看别人用的上面版本的jar包,然后才开始搭建,不然后期遇到问题真的很难发现。