Maven SpringMVC整合Mybatis

关于Spring的核心理念和Mybatis的优点网上已经有很多文档做了说明。这篇博客，只记录springmvc整合mybatis时常见的知识点，以及注意事项，它只有最精简的几个模块，以帮助初学者迅速搭建框架，建立一个比较对ssm框架比较全面的认识

Eclipse 搭建Maven web项目

• File-->New-->Maven Project
  
  

*Next

*选择maven webapp项目 点击next

• 填好maven项目坐标 groupId,artifactId,点击next
  
  

*初始项目目录结构如下

开始时会有报错，是应为没有javax.servlet-api.jar，待会儿在pom.xml中添加相关依赖就行了

*在main目录下添加java目录，在src目录下添加test目录，在test目录下添加java目录

因为在build path-->configure build path 后进入的这个页面中，可以看见少了这2个目录

*在pom.xml文件中添加相关依赖

<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.ws</groupId>
    <artifactId>SSM</artifactId>
    <packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <name>SSM Maven Webapp</name>
    <url>http://maven.apache.org</url>
    <properties>
        <spring.version>4.3.2.RELEASE</spring.version>
        <!-- <mysql-connector-java.version>5.1.34</mysql-connector-java.version> -->
    </properties>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>

        <!-- spring start -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>${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-context-support</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</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-orm</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${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>
        <!-- spring end -->

        <!-- mybatis start -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.2.8</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.3.0</version>
        </dependency>
        <!-- mybatis end -->

        <!-- mysql -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.45</version>
        </dependency>
        <!-- 数据库连接池，这里我们的项目并没有使用这个连接池，使用的是spring jdbc中的一个连接池，不同的连接池，
        在配置数据源的时候，属性名可能是不同的，需要自己查看先关的类，比如有的驱动名是 driverClass 有的是 driverClassName -->
        <dependency>
            <groupId>commons-dbcp</groupId>
            <artifactId>commons-dbcp</artifactId>
            <version>1.4</version>
        </dependency>  

        <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.0.1</version>
        <scope>provided</scope>
        </dependency>

    </dependencies>
    <build>
        <finalName>SSM</finalName>
    </build>
</project>

• 然后配置web.xml文件

<web-app version="2.5" 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/javaee http://java.sun.com/xml/ns/j2ee/web-app_2_5.xsd">
    <!-- J2EE容器添加的上下文 -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>

   <!-- Spring监听 -->
   <listener>
     <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
   </listener> 

   <!-- Spring MVC配置 -->
   <servlet>
     <servlet-name>Dispatcher</servlet-name>
     <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
     <!-- 自定义spring mvc的配置文件名称和路径 -->
     <init-param>
       <param-name>contextConfigLocation</param-name>
       <param-value>classpath:spring-servlet.xml</param-value>
     </init-param>
     <load-on-startup>1</load-on-startup>
   </servlet> 

   <!-- spring mvc 请求后缀 -->
   <servlet-mapping>
     <servlet-name>Dispatcher</servlet-name>
     <url-pattern>*.action</url-pattern>
   </servlet-mapping> 

   <welcome-file-list>
     <welcome-file>index.jsp</welcome-file>
   </welcome-file-list> 

</web-app>

• 在main-->resources目录下添加spring-servlet.xml文件，用来管理springmvc的配置

<?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:aop="http://www.springframework.org/schema/aop"
    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-4.2.xsd
      http://www.springframework.org/schema/aop
      http://www.springframework.org/schema/aop/spring-aop-4.2.xsd
      http://www.springframework.org/schema/mvc
      http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context-4.2.xsd">

      <!-- 启用spring mvc 注解 -->
    <context:annotation-config />
    <mvc:annotation-driven />

    <!-- 设置使用注解的类所在的jar包 -->
    <context:component-scan base-package="com.ws.controller" />

    <!-- 配置试图渲染器 -->
    <bean  id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
     <property name="prefix" value="/WEB-INF/jsp/" />
     <property name="suffix" value=".jsp" />
   </bean> 

</beans>

• 在main-->resources目录下添加jdbc.properties 配置文件
  
  这里有一些需要注意的地方，一是结尾不要有空格，二是设置用户名时不要用username,因为可能会跟系统的其他配置有冲突，我就是因为这个问题，找了很久错误

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/mybatis
user=root
password=123456

*在main-->resources目录下添加applicationContext.xml文件，用来管理spring bean对象，及整合mybatis

<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:util="http://www.springframework.org/schema/util" xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd
    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd">
    <!-- 引入jdbc配置文件，在下文中就可以通过${name}来使用值 -->
    <context:property-placeholder location="classpath:jdbc.properties" />

    <bean id="dataSource" class="org.springframework.jdbc.datasource.SimpleDriverDataSource">
        <property name="driverClass" value="${driver}" />
        <property name="url" value="${url}" />
        <property name="username" value="${user}" />
        <property name="password" value="${password}" />
    </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>

    <!-- 创建SqlSessionFactory，同时指定数据源 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <!-- 指定mapper xml文件的路径 你可以放在resources目录下，然后通过classpath来引入 -->
        <property name="mapperLocations" value="classpath:mapping/*.xml" />
    </bean>

    <!-- Mapper接口所在包名，Spring会自动查找其下的Mapper ，mybatis会自动通过xml映射文件，生成相应的代码，然后通过mapper 接口来调用相关的操作-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.ws.mapper" />
    </bean>

    <!-- 可通过注解控制事务 -->
    <tx:annotation-driven />

</beans>

• 在java目录下新建如下几个包
  
  

*在bean中加入User类

package com.ws.bean;

public class User {
    private String name;
    private int age;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
}

*在mapper中加入UserMapper 接口

package com.ws.mapper;

import org.springframework.stereotype.Repository;
import com.ws.bean.User;

@Repository
public interface UserMapper{
    public User  getUserInfoByName(String name);
}

*在resources目录下添加mapping文件夹，并创建UserMapper.xml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" >

<!-- 这块等于dao接口的实现，namespace必须和接口的类路径一样 -->
<mapper namespace="com.ws.mapper.UserMapper">
<!-- mapper接口中的函数应该和id所设置的相同，如果没有为自定义类型设置别名，则需要使用完整的包加类名 -->
    <select id="getUserInfoByName" parameterType="String" resultType="com.ws.bean.User">
        select * from user where name=#{name}
    </select> 

</mapper>

*将index.jsp文件改成如下

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<html>
<head>
    <meta charset="utf-8" />
</head>
<body>
<h2>Hello World!</h2>
<a href="test.action?name=ws">点击跳转</a>
</body>
</html>

*在WEB-INF目录下新建一个jsp目录，并创建一个User.jsp,内容如下

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!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>Insert title here</title>
</head>
<body>
Hello ${user.name } ${user.age }
</body>
</html>

*在controller包中添加如下Test 控制器 ，代码如下

package com.ws.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.ImportResource;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import com.ws.bean.User;
import com.ws.mapper.UserMapper;
import javax.annotation.Resource;
@Controller
public class Test {
    @Autowired
    private UserMapper userService;

    @RequestMapping(value="test")
    public String test(@RequestParam("name") String name ,Model model){
        User user=null;
        user=userService.getUserInfoByName(name);
        model.addAttribute(user);
        return "User";
    }
}

• 在mysql中创建名为mybatis 的数据库和user表

  create database mybatis;
  
  use mybatis;
  
  create table user(
  
  name varchar(255),
  
  age int
  
  );
  
  insert into user values("ws",21);

• 至此整个框架已经搭建完成，放在tomcat中运行
  
  

这知识一个最小的模快，后续还会添加更多的功能