spring整合mybatis

项目的目录结构如下：

第一步:新建好一个maven项目,引入pom文件的依赖：

<?xml version="1.0" encoding="UTF-8"?>
<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.itcast</groupId>
      <artifactId>DemoMy</artifactId>
      <packaging>war</packaging>
      <version>0.0.1-SNAPSHOT</version>
  
    <dependencies>

<!-- https://mvnrepository.com/artifact/org.mybatis.generator/mybatis-generator-core -->
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>1.3.5</version>
</dependency>

<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<!--Spring-MVC、Spring-->
<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-test -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>4.3.7.RELEASE</version>
<scope>test</scope>
</dependency>

<!--JSR303数据校验,
导入Hibernate-Validator
tomcat7以下的服务器，el表达式,额外给服务器的lib包中替换新的标准的el-->
<!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-validator -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.4.1.Final</version>
</dependency>

<!--分页查询插件-->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>5.0.0</version>
</dependency>

<!--返回JSON字符串的支持-->
<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.8.8</version>
</dependency>


<!--Spring JDBC 事务管理-->
<!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>
<!--Spring 面向切面编程-->
<!-- https://mvnrepository.com/artifact/org.springframework/spring-aspects -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>

<!--MyBatis-Jar包-->
<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.2</version>
</dependency>

<!--MyBatis 整合Spring适配包-->
<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis-spring -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.1</version>
</dependency>

<!-- https://mvnrepository.com/artifact/com.mchange/c3p0 -->
<dependency>
    <groupId>c3p0</groupId>
    <artifactId>c3p0</artifactId>
    <version>0.9.1.2</version>
</dependency>

<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.12</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-beans</artifactId>
    <version>4.3.7.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.servlet/servlet-api -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>RELEASE</version>
</dependency>

</dependencies>
<build>
 <plugins>
       <plugin>
             <groupId>org.apache.maven.plugins</groupId>
             <artifactId>maven-compiler-plugin</artifactId>
             <version>3.1</version>
             <configuration>
                 <source>1.8</source>     
                 <target>1.8</target>      
             </configuration>
       </plugin>
  </plugins>
</build>
</project>

第二部：新建pojo类：

package cn.itcast.mybatis.po;
import java.util.Date;
public class User {
    
    private static final long serialVersionUID = 1L;
    private Integer id;
    private String username;
    private String sex;
    private Date birthday;
    private String address;


    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getSex() {
        return sex;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
    public Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
    @Override
    public String toString() {
        return "User [id=" + id + ", username=" + username + ", sex=" + sex
                + ", birthday=" + birthday + ", address=" + address + "]";
    }

    
}

第三步：新建UserMapper接口。

package cn.itcast.mybatis.po;

public interface UserMapper {
　　　　public User findUserById(Integer id);

}

第四步：在src/main/resources下面新建文件夹mapper， 在mapper下新建UserMapper.xml 

<?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">
<!-- 写Sql语句   -->
<mapper namespace="cn.itcast.mybatis.po.UserMapper">

    <!-- 通过ID查询一个用户 -->
    <select id="findUserById" parameterType="Integer" resultType="User">
        select * from user where id = #{id}
    </select>
       
</mapper>

第四步：在resources下面新建spring的配置文件applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context" 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:xsi="http://www.w3.org/2001/XMLSchema-instance"
       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
    http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
    http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd">

    <!-- 加载配置文件 -->
    <context:property-placeholder location="classpath:db.properties" />

    <!--数据库连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.uid}"/>
        <property name="password" value="${jdbc.password}"/>
        <!-- 初始连接池大小 -->
        <property name="initialPoolSize" value="10"/>
        <!-- 连接池中连接最小个数 -->
        <property name="minPoolSize" value="5"/>
        <property name="maxPoolSize" value="20"/>
     </bean>

    <!-- 配置mybatis的工厂 SqlSessionFactory -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
         <!-- 配置mybatis核心配置文件 -->
        <property name="configLocation" value="classpath:SqlMapConfig.xml" />
        <!-- 配置数据源 -->
        <property name="dataSource" ref="dataSource" />
    </bean>
    
    <!--配置userMapper对象-->
      <bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
           <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
            <property name="mapperInterface" value="cn.itcast.mybatis.po.UserMapper" />
    </bean>
    
</beans>

第五步：resources下配置数据库连接 db.properties：

#jdbc.driver=com.mysql.jdbc.Driver
jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://192.168.1.20:3306/test?serverTimezone=UTC&useSSL=false
jdbc.uid=root
jdbc.password=root123

然后在resources下新建日志文件：log4j.properties

# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

第六步：在resources下面新建mybatis的配置文件 SqlMapConfig.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>
      
    <!-- 设置别名 --> <!-- 2. 指定扫描包，会把包内所有的类都设置别名，别名的名称就是类名，大小写不敏感 -->
    <typeAliases>
        <typeAlias alias="User" type="cn.itcast.mybatis.po.User"/>
    </typeAliases>

    <!--加载userMapper.xml文件，也可以在spring配置文件加载全部的mapper.xml文件  -->
    <mappers>
        <mapper resource="mapper/UserMapper.xml"/>
    </mappers>
    

<!-- 2. 指定扫描包，会把包内所有的类都设置别名，别名的名称就是类名，大小写不敏感 -->
<!-- <package name="com.yyb.pojo" /> -->

</configuration>

第七部： 新建测试类：

@org.junit.Test
        public void func1() throws Exception {
            ApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
            UserMapper mapper=ac.getBean(UserMapper.class);
            User user = mapper.findUserById(1);
            System.out.println(user);
        }

结果：