<dependencies><!--mybatis--><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.4.6</version></dependency><!--数据库相关 jar 包--><dependency><groupId>org.mariadb.jdbc</groupId><artifactId>mariadb-java-client</artifactId><version>2.3.0</version></dependency><!-- JUnit单元测试工具 --><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.10</version></dependency></dependencies>

CREATE TABLE BOOK(
ID INT AUTO_INCREMENT PRIMARY KEY,
NAME VARCHAR(20),
NUMBER int );
insert into BOOK(NAME,NUMBER) VALUES
('Java程序设计',10),
('数据结构',10),
('设计模式',10)

package com.wbg.entity;public class Book {int id;String name;int number;@Overridepublic String toString() {return "Book{" +"id=" + id +", name='" + name + '\'' +", number=" + number +'}';}public int getId() {return id;}public void setId(int id) {this.id = id;}public Book() {}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getNumber() {return number;}public void setNumber(int number) {this.number = number;}public Book(int id, String name, int number) {this.id = id;this.name = name;this.number = number;}
}

View Code

package com.wbg.dao;import com.wbg.entity.Book;public interface bookMapper {Book selectBookById();
}

package com.wbg.dao;import com.wbg.entity.Book;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;import java.io.InputStream;public class BookDao {public Book getBookById(int id){//使用类加载器加载mybatis的配置文件InputStream inputStream=BookDao.class.getClassLoader().getResourceAsStream("config.xml");//构建sqlSession的工厂SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);//创建能执行映射文件中的sqlSqlSession sqlSession=sqlSessionFactory.openSession();Book book=sqlSession.selectOne("com.wbg.dao.bookMapper.selectBookById",2);return book;}public static void main(String[] args) {BookDao bookDao=new BookDao();System.out.println(bookDao.getBookById(1));}
}

View Code

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><environments default="development"><environment id="development"><transactionManager type="JDBC"/><dataSource type="POOLED"><property name="driver" value="org.mariadb.jdbc.Driver"/><property name="url" value="jdbc:mariadb://localhost:3306/stu"/><property name="username" value="root"/><property name="password" value="123456"/></dataSource></environment></environments><mappers><mapper resource="mapper/bookMapper.xml"/></mappers>
</configuration>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.wbg.dao.bookMapper"><select id="selectBookById" resultType="com.wbg.entity.Book">select * from Book where id=#{id}</select>
</mapper>