参考官方文档:http://www.mybatis.org/mybatis-3/zh/index.html
环境:IDEA、Java8、maven、mybatis、log4j
实践内容:搭建mybatis环境之配置文件xml版
github源码:https://github.com/githubgxr/mybatis
使用IDEA maven创建java项目。
项目结构:
pom.xml导入log4j、mybatis、数据库连接驱动
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.6</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.25</version>
</dependency>
<!-- log -->
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-api -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.25</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-log4j12 -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.25</version>
<!-- <scope>test</scope> -->
</dependency>
创建jdbc.properties文件,在mybatis-configuration.xml中引入
username=root
password=root
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/test
配置log4j.properties
# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# MyBatis logging configuration...
log4j.logger.org.mybatis.example.BlogMapper=TRACE
# 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
创建实体类User
package com.demo.entity;
public class User {
private int id;
private String name;
private String password;
public String getName() {
return name;
}
public String getPassword() {
return password;
}
public void setName(String name) {
this.name = name;
}
public void setPassword(String password) {
this.password = password;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", password='" + password + '\'' +
'}';
}
}
创建实体类User的映射文件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">
<mapper namespace="com.demo.entity.User">
<select id="findAll" resultType="com.demo.entity.User">
select * from user
</select>
<select id="selectOne" resultType="com.demo.entity.User">
select * from user where id=#{id}
</select>
<insert id="addUser"
useGeneratedKeys="true"
keyProperty="id">
insert into user (name,password) values (#{username},#{password})
</insert>
</mapper>
配置mybatis-configuration.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">
<!--获取数据库连接实例的数据源(DataSource)和决定事务作用域和控制方式的事务管理器(TransactionManager)-->
<configuration>
<!--把-->
<properties resource="jdbc.properties">
<property name="username" value="root" />
<!--启动给占位符${}指定默认值的特性-->
<property name="org.apache.ibatis.parsing.PropertyParser.enable-default-value" value="true"/>
</properties>
<!--会改变 MyBatis 的运行时行为-->
<settings>
<!--使用log4j日志组件-->
<setting name="logImpl" value="LOG4J"/>
</settings>
<environments default="development">
<!--每个 environment 元素定义的环境 ID(比如:id="development")-->
<environment id="development">
<!--事务管理器-->
<!--JDBC – 这个配置就是直接使用了 JDBC 的提交和回滚设置,它依赖于从数据源得到的连接来管理事务作用域。-->
<transactionManager type="JDBC"/>
<!--数据源-->
<!--POOLED– 这种数据源的实现利用“池”的概念将 JDBC 连接对象组织起来,避免了创建新的连接实例时所必需的初始化和认证时间。 这是一种使得并发 Web 应用快速响应请求的流行处理方式。-->
<dataSource type="POOLED">
<property name="driver" value="${driver}"/>
<property name="url" value="${url}"/>
<property name="username" value="${username}"/>
<!--给${username}占位符指定默认值ut_user-->
<!--<property name="username" value="${username:ut_user}"/>-->
<property name="password" value="${password}"/>
</dataSource>
</environment>
</environments>
<mappers>
<!--配置实体类User的映射文件的位置-->
<mapper resource="mapper/UserMapper.xml"/>
</mappers>
</configuration>
创建Application并运行测试是否搭建成功
import com.demo.entity.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.apache.log4j.spi.RootLogger;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Reader;
import java.util.List;
public class Application {
public static void main(String[] args) throws Exception {
String resource = "mybatis-configuration.xml";
Reader reader = Resources.getResourceAsReader(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
SqlSession session = sqlSessionFactory.openSession();
List<User> list= session.selectList("com.demo.entity.User.findAll", User.class);
for (User u:list
) {
System.out.printf(u.toString());
}
}
}
运行结果:
数据库内容:
运行结果与数据库内容一致——>环境搭建成功。
总结
- 创建项目
- pom.xml添加mybatis、log4j、数据库连接驱动等依赖
- 配置jdbc.properties
- 配置log4j.properies
- 配置mybatis文件mybatis-configuration.xml
- 运行测试是否搭建成功
6.1 创建SqlSessionFactory实例
6.2 创建SqlSession实例
6.3 使用SqlSession实例CRUD
ps:虚心求教。如果内容有误欢迎指出,如果内容帮助了你欢迎留下痕迹。