引入 Mybatis 依赖架包
复制以下代码到 porm.xml 文件里
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.10</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.22</version>
</dependency>添加核心配置文件
添加 src/main/resources/mybatis3.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">
<!-- 通过这个配置文件完成mybatis与数据库的连接 -->
<configuration>
<!-- 配置mybatis的log实现为LOG4J -->
<settings>
<setting name="logImpl" value="LOG4J"/>
</settings>
<environments default="test">
<environment id="test">
<!--配置事务管理，采用JDBC的事务管理 -->
<transactionManager type="JDBC"></transactionManager>
<!-- POOLED:mybatis自带的数据源，JNDI:基于tomcat的数据源 -->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="url"
value="jdbc:mysql://localhost:3306/air?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true"/>
<property name="username" value="root"/>
<property name="password" value="995983"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="mappers/UserMapper.xml"/>
</mappers>
</configuration>修改数据库地址、数据库名、用户和密码
<property name="url"
value="jdbc:mysql://localhost:3306/air?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true"/>
<property name="username" value="root"/>
<property name="password" value="995983"/>添加工具类
src/main/java/com/oracle/y6/mybatis/utils/MyBatisUtil.java
package com.oracle.y6.mybatis.utils;
import java.io.IOException;
import java.io.InputStream;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
public class MyBatisUtil {
private static SqlSessionFactory factory;
static{//在静态代码块下，factory只会被创建一次
try {
InputStream is = Resources.getResourceAsStream("mybatis3.xml");
factory = new SqlSessionFactoryBuilder().build(is,"test");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static SqlSession createSqlSession(){
return factory.openSession(true);//true 为自动提交事务
}
public static void closeSqlSession(SqlSession sqlSession){
if(null != sqlSession)
sqlSession.close();
}
}添加日志跟踪
porm.xml
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>添加日志配置 src/main/resources/log4j.properties
log4j.rootLogger=info,CONSOLE
#log4j.rootLogger=ERROR,ROLLING_FILE
log4j.logger.com.oracle.y6.mybatis.mappers=TRACE
log4j.logger.com.ibatis=info
log4j.logger.com.ibatis.common.jdbc.SimpleDataSource=info
log4j.logger.com.ibatis.common.jdbc.ScriptRunner=info
log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate=info
log4j.logger.java.sql.Connection=info
log4j.logger.java.sql.Statement=trace
log4j.logger.java.sql.PreparedStatement=debug
log4j.logger.java.sql.ResultSet=debug
#log4j.logger.org.tuckey.web.filters.urlrewrite.UrlRewriteFilter=debug
######################################################################################
# Console Appender \u65e5\u5fd7\u5728\u63a7\u5236\u8f93\u51fa\u914d\u7f6e
######################################################################################
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.Threshold=error
log4j.appender.CONSOLE.Target=System.out
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern= [%p] %d %c - %m%n
log4j.logger.com.opensymphony.xwork2=error
测试环境junit
添加类src/test/java/TestMybatis.java
import com.oracle.y6.mybatis.utils.MyBatisUtil;
import org.apache.ibatis.session.SqlSession;
import org.junit.jupiter.api.Test;
public class TestMybatis {
@Test
public void test1()
{
SqlSession ss= MyBatisUtil.createSqlSession();
System.out.println(ss);
}
@Test
public void test2()
{
System.out.println("测试");
}
}实现第一个查询
添加实体类 src/main/java/com/oracle/y6/mybatis/entity/User.java
package com.oracle.y6.mybatis.entity;
public class User {
private String username;
private String password;
private Double banlance;
public String getUsername() {
return username;
}
public Double getBanlance() {
return banlance;
}
public String getPassword() {
return password;
}
public void setUsername(String username) {
this.username = username;
}
public void setPassword(String password) {
this.password = password;
}
public void setBanlance(Double banlance) {
this.banlance = banlance;
}
}添加接口 src/main/java/com/oracle/y6/mybatis/mappers/UserMapper.java
package com.oracle.y6.mybatis.mappers;
import com.oracle.y6.mybatis.entity.User;
import java.util.List;
public interface UserMapper {
public List<User> findUser();
}添加映射文件
src/main/resources/mappers/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.oracle.y6.mybatis.mappers.UserMapper">
<select id="findUser" resultType="com.oracle.y6.mybatis.entity.User">
select * from user
</select>
</mapper>注册映射文件添加到 src/main/resources/mybatis3.xml
<mappers>
<mapper resource="mappers/UserMapper.xml"/>
</mappers>测试UserMapper
import com.oracle.y6.mybatis.entity.User;
import com.oracle.y6.mybatis.mappers.UserMapper;
import com.oracle.y6.mybatis.utils.MyBatisUtil;
import org.apache.ibatis.session.SqlSession;
import org.junit.jupiter.api.Test;
public class UserMapperTest {
@Test
public void testFinderUser() {
SqlSession ss = MyBatisUtil.createSqlSession();
UserMapper mapper = ss.getMapper(UserMapper.class);
mapper.findUser();
}
}