第一个maven下的mybatis项目

pom.xml配置如下

<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/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.itcast.mybatis01</groupId>
    <artifactId>mybatis01</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
    
<!--导入mybatis依赖-->
        <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.2.7</version>
        </dependency>

<!--需要用到mysql包依赖-->
        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.36</version>
        </dependency>


<!--配置log4j。同时不要忘记建立log4j.properties-->
        <dependency>
            <groupId>org.bgee.log4jdbc-log4j2</groupId>
            <artifactId>log4jdbc-log4j2-jdbc4.1</artifactId>
            <version>1.16</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.13</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.5</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/log4j/log4j -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.16</version>
        </dependency>
    </dependencies>

</project>

log.properties配置如下：

# 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

在资源目录下创建SqlMapConfig.xml

配置如下：

<?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>
  <environments default="development">
    <environment id="development">
      <transactionManager type="JDBC"/>
      <dataSource type="POOLED">
        <property name="driver" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/web_test3"/>
        <property name="username" value="root"/>
        <property name="password" value="admin"/>
      </dataSource>
    </environment>
  </environments>
  <mappers>
    <mapper resource="mapper.xml"/>
  </mappers>
</configuration>    

创建mapper.xml配置文件

<?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">

  <!--在这里namespace="test" 随便写的，后面再研究-->
 
  <mapper namespace="test">
  
  <!--
    resultType:表示我们的结果类型
    parameterType:表示我们的参数的类型
    在mybatis中使用#{}来做我们的占位符
  -->
  <select id="getUserNameByID" resultType="mybatis01.dao.User" parameterType="int">
  select * from user where id = #{id}
  </select>

    <select id="getUserByAddress" resultType="mybatis01.dao.User" parameterType="string">
  select * from user where nickname like '%${value}%'
  </select>


</mapper>

根据数据表中数据属性创建Uer对象,并生成getter/setter方法

创建MybatisFirst类：

public class MybatisFirst {

    private SqlSession openSession;

    @Test
    public void getUserNameByID() throws IOException {
        User userObj = openSession.selectOne("getUserNameByID", 6);
        System.out.println(userObj.getNickname());
    }

    
    // 注解Before  ：每次方法执行前都会执行这里
    @Before  
    public void init() throws IOException {

        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        SqlSessionFactory build = builder.build(Resources.getResourceAsStream("SqlMapConfig.xml"));
        openSession = build.openSession();
        
    }
    

    @Test
    public void getUserByAddress()throws IOException {
        List<User> userList = openSession.selectList("getUserByAddress", "花花");
        
        for (User usrObj : userList) {
            System.out.println(usrObj.getNickname());
        }
    }
}

运行即可

记得maven配置文件的镜像地址改成阿里云的。并修改自己本地仓库的保存路径；

maven阿里云镜像如下:

<mirror>
     <id>nexus-aliyun</id>
     <mirrorOf>*</mirrorOf>
     <name>Nexus aliyun</name>
     <url>http://maven.aliyun.com/nexus/content/groups/public</url>
</mirror>