mybatis environment to build (eclipse)

Create a maven project

Use eclipse

• create maven project

• Select create a simple project ()

• Input group id, artifact id

  Project structure:

maven configuration is as follows:

<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.getword</groupId>
  <artifactId>simple1</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <!--设置源代码编码-->
  <properties>
    <project.build.sourceEncoding>utf-8</project.build.sourceEncoding>
  </properties>
   
  <dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.3.0</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.38</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.12</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.7.12</version>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
    </dependency>
  </dependencies>
    
    <!--设置编译源代码的jdk版本-->
  <build>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
            </configuration>
        </plugin>
    </plugins>
  </build>
</project>

mybatis basic configuration

• mybatis-config.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>
    <settings>
        <!-- 通过配置属性logImpl，指定使用LOG4J输出日志 -->
        <setting name="logImpl" value="LOG4J"/>
    </settings>
    <!-- 配置一个包的别名 在使用类的时候不用指定类的全限定名称 -->
    <typeAliases>
        <package name="com.getword.domain"/>
    </typeAliases>
    
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC">
                <property name="" value=""/>
            </transactionManager>
            <dataSource type="UNPOOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/train"/>
                <property name="username" value="root"/>
                <property name="password" value="123"/>
            </dataSource>
        </environment>
    </environments>
    
    <mappers>
        <mapper resource="mapper/UserMapper.xml"/>
    </mappers>
</configuration>

log4j log

• In the resources below, the new log4j.properties file, note the file name and a fixed location

# 
log4j.rootLogger=ERROR, stdout

# mybatis config
log4j.logger.com.getword.mapper=trace # com.getword.mapper->namespace

# console
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConverionPattern=%5p [%t] - %m%n

• more

log4j.rootLogger=DEBUG, Console

#Console
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.layout=org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n

log4j.logger.java.sql.ResultSet=INFO
log4j.logger.org.apache=INFO
log4j.logger.java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

mapper

<?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">
<!-- namespace定义当前xml的命名空间,就是包名 -->
<mapper namespace="com.getword.mapper.UserMapper">
    <select id="selectAll" resultType="User">
        select * from tb_user;
    </select>
</mapper>

• test

public class UserMapperBootstrap {
    private static SqlSessionFactory sqlSessionFactory;
    
    @BeforeClass
    public static void init() {
        try {
            // 通过Resource工具类将配置文件读入Reader
            Reader reader = Resources.getResourceAsReader("mybatis-config.xml");
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
            reader.close();
        }catch(IOException ignore) {
            ignore.printStackTrace();
        }
        
    }
    
    @Test
    public void testSelectAll() {
        SqlSession session = sqlSessionFactory.openSession();
        List<User> users = session.selectList("selectAll"); // 没使用命名空间全路径
        printUsers(users);
        session.close();
        
    }
    public void printUsers(List<User> users) {
        for (User user : users) {
            System.out.println(user);
        }
    }
}