Mybatis基础环境配置模板
1.mybatis环境基础配置概述
1.创建一个maven工程
2.在pom.xml中导入mybatis相关的依赖，以及操作数据库相关的文件配置依赖
3.在resource下创建mybatis的配置文件，一般名字为mybatis-config.xml
4.创建与数据库对应的实体类
5.创建mapper接口
6.在resource下创建与mapper接口相对应的sql映射文件
2.基础环境详细教程
2.1 创建maven工程
此处省略，创建成功后截图如下
2.2 导入相关的依赖文件(简单版本版本)
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatisartifactId>
<version>3.5.7version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>8.0.25version>
dependency>
<dependency>
<groupId>log4jgroupId>
<artifactId>log4jartifactId>
<version>1.2.17version>
dependency>
<dependency>
<groupId>org.junit.jupitergroupId>
<artifactId>junit-jupiterartifactId>
<version>RELEASEversion>
<scope>compilescope>
dependency>
2.3 在resource下配置mybatis配置文件MyBatisConfig.xml(简单版本版本)
DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<properties resource="jdbc.properties"/>
<settings>
<setting name="logImpl" value="LOG4J"/>
settings>
<typeAliases>
<package name="com.tz.entity"/>
typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="${driver}"/>
<property name="url" value="${url}"/>
<property name="username" value="${username}"/>
<property name="password" value="${password}"/>
dataSource>
environment>
environments>
<mappers>
<package name="com.tz.mapper"/>
mappers>
configuration>
2.4 创建与数据库对应的实体类
字段名和数据库名字保持一致，如果不一致可以在MyBatisConfig.xml配置文件中设置，或者是配置开启驼峰命名
2.5 创建实体类对应的mapper接口
mapper接口作用就是写增删改查的抽象方法
2.6 在resource下创建与mapper接口相对应的sql映射文件
DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="StudentMapper">
<select id="selectAll" resultType="com.iflytek.bean.Student">
SELECT * FROM student
select>
mapper>
2.7 连接工具类
在 com.iflytek 包下创建 utils 包，并在该包下创建名为 SqlSessionFactoryUtils 工具类
public class SqlSessionFactoryUtils {
private static SqlSessionFactory sqlSessionFactory;
static {
//静态代码块会随着类的加载而自动执行，且只执行一次
try {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
}
public static SqlSessionFactory getSqlSessionFactory(){
return sqlSessionFactory;
}
}
3.必须配置的配置文件总结
3.1 导入依赖文件
这里的配置文件给出了详细的依赖。
<dependencies>
<dependency>
<groupId>log4jgroupId>
<artifactId>log4jartifactId>
<version>1.2.12version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatisartifactId>
<version>3.5.6version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>8.0.31version>
dependency>
<dependency>
<groupId>junitgroupId>
<artifactId>junitartifactId>
<version>4.11version>
dependency>
<dependency>
<groupId>javax.servletgroupId>
<artifactId>javax.servlet-apiartifactId>
<version>3.1.0version>
<scope>providedscope>
dependency>
<dependency>
<groupId>javax.servlet.jspgroupId>
<artifactId>jsp-apiartifactId>
<version>2.2version>
<scope>providedscope>
dependency>
<dependency>
<groupId>jstlgroupId>
<artifactId>jstlartifactId>
<version>1.2version>
dependency>
<dependency>
<groupId>taglibsgroupId>
<artifactId>standardartifactId>
<version>1.1.2version>
dependency>
dependencies>
3.2 在resource下的文件配置
3.2.1 mybatis-config核心配置文件，所有其它配置文件都需要在这里面配置加载
DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<properties resource="jdbc.properties"/>
<settings>
<setting name="logImpl" value="LOG4J"/>
<setting name="mapUnderscoreToCamelCase" value="true"/>
settings>
<typeAliases>
<package name="com.tz.entity"/>
typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="${driver}"/>
<property name="url" value="${url}"/>
<property name="username" value="${username}"/>
<property name="password" value="${password}"/>
dataSource>
environment>
environments>
<mappers>
<package name="com.tz.mapper"/>
mappers>
configuration>
3.2.2 在resource配置mapper映射文件
DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.tz.mapper.BrandMapper">
<select id="selectAll" resultType="com.tz.entity.Brand">
select * from tb_brand;
select>
mapper>
注意:
namespace名字一定要和mapper接口保持一致
id一定要和mapper接口的方法保持一致，为后面的方向代理做准备
3.2.3 log4j.properties配置
文件名字必须为log4j.properties
log4j.rootLogger=DEBUG,console
########################控制台输出的相关设置
log4j.appender.console = org.apache.log4j.ConsoleAppender
#在控制台输出
log4j.appender.console.Target = System.out
#在DEBUG级别输出
log4j.appender.console.Threshold = DEBUG
log4j.appender.console.layout = org.apache.log4j.PatternLayout
#日志格式
log4j.appender.console.layout.ConversionPattern=[%c]-%m%n
######################日志输出级别
log4j.logger.org.mybatis=DEBUG
log4j.logger.java.sql=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG
3.2.4 jdbc.properties
文件名字必须为jdbc.properties
driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql:///db1
username=root
password=123456
3.4 配置mybatis连接工具类
工具类类名为：SqlSessionFactoryUtils
public class SqlSessionFactoryUtils {
private static SqlSessionFactory sqlSessionFactory;
static {
//静态代码块会随着类的加载而自动执行，且只执行一次
try {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
}
public static SqlSessionFactory getSqlSessionFactory(){
return sqlSessionFactory;
}
}