mybatis环境配置

<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>

　　导入依赖

 <dependency>
  <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.5.10</version>
</dependency>

<dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.29</version>
    </dependency>

<build>
    <resources>
      <resource>
        <directory>src/main/resources</directory>
        <includes>
          <include>**/*.properties</include>
          <include>**/*.xml</include>
        </includes>
        <filtering>true</filtering>
      </resource>
      <resource>
        <directory>src/main/java</directory>
        <includes>
          <include>**/*.properties</include>
          <include>**/*.xml</include>
        </includes>
        <filtering>true</filtering>
      </resource>
</build>

resource目录下资源文件

db.properties

driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/mydb?characterEncoding=UTF-8
user=root
port=3306
pwd=123456

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>
    <!-- 数据库连接配置文件 -->
    <properties resource="db.properties"/>
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <!-- 数据库环境配置，可配置多套。default指出当前使用的是哪个环境。 -->
    <environments default="dev">
        <environment id="dev">
            <transactionManager type="JDBC" />
            <!-- 配置数据库连接 -->
            <dataSource type="POOLED">
                <property name="driver" value="${driver}" />
                <property name="url"    value="${url2}" />
                <property name="username" value="${user}" />
                <property name="password" value="${pwd}" />
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="com/iit/dao/GoodMapper.xml"/>
        <mapper resource="com/iit/dao/UserMapper.xml"/>
        <mapper resource="com/iit/dao/SqlMapper.xml"/>
    </mappers>
</configuration>

连接池连接

driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/mydb?characterEncoding=UTF-8
user=root
port=3306
pwd=123456
initialSize=2
maxActive=3
minIdle=2
maxWait=2000
poolPreparedStatements=true

<?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>
    <!-- 数据库连接配置文件 -->
    <properties resource="db.properties"/>
    <settings>
        <!--   打印日志-->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
<!--   字段名属性处理     -->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
    <typeAliases>
        <!-- 别名设置-->
        <typeAlias type="com.iit.pojo.User" alias="user"/>
    </typeAliases>
    <!-- 数据库环境配置，可配置多套。default指出当前使用的是哪个环境。 -->
    <environments default="dev">
        <!-- 连接环境信息 -->
        <environment id="dev">
            <!-- mysql使用什么事物管理方式 -->
            <transactionManager type="JDBC"/>
            <!-- mybatis使用连接池方式来获取连接对象 -->
            <dataSource type="com.iit.utils.DruidDataSourceFactory">
                <property name="driverClass" value="${driver}"/>
                <property name="jdbcUrl" value="${url}"/>
                <property name="username" value="${user}"/>
                <property name="password" value="${pwd}"/>
                <property name="initialSize" value="${initialSize}"/>
                <property name="maxActive" value="${maxActive}"/>
                <property name="minIdle" value="${minIdle}"/>
                <property name="maxWait" value="${maxWait}"/>
                <property name="poolPreparedStatements" value="${poolPreparedStatements}"/>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <!-- 注册-->
        <mapper resource="com/iit/dao/UserMapper.xml"/>
        <mapper resource="com/iit/dao/SqlMapper.xml"/>
    </mappers>
</configuration>

插入一个类

package com.iit.utils;

import com.alibaba.druid.pool.DruidDataSource;
import org.apache.ibatis.datasource.pooled.PooledDataSourceFactory;

public class DruidDataSourceFactory extends PooledDataSourceFactory {
    public DruidDataSourceFactory(){
        this.dataSource = new DruidDataSource();
    }
}