study Mybatis step by step
[*]
简单查询
一、首先创建下载mybatis的相关jar包和数据库的相关jar包，mybatis的jar包的官方下载地址http://mybatis.github.io/
二、建立一个java项目并且将刚才下在的jar包放在相应的文件下面，然后参照到项目中
三、建立mybatis-config.xml 配置文件如下：<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.2//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!-- properties for the mybatis configuration -->
<properties>
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/test"/>
<property name="username" value="root"/>
<property name="password" value=""/>
</properties>
<!-- java type mapping -->
<typeAliases>
<typeAlias alias="Course"type="com.mybatis.in.Course"/>
</typeAliases>
<!-- environment configuration -->
<environments default="development">
<environment id="development">
<transactionManager type="JDBC">
</transactionManager>
<!-- database connection configuration -->
<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>
<!-- mapper configuration file -->
<mappers>
<mapper resource="com/test/mybatis/CourseMapper.xml"/>
</mappers>
</configuration>
四、在com.test.mybatis下面建立一个CourseMapper.xml作为course的映射配置文件
<?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">
<!-- configuration for course mapper -->
<mapper namespace="com.mybatis.in.CourseMapper">
<!-- mapping the course table and java course type-->
<resultMap id="courseMap" type="Course">
<id property="courseId" column="courseId"/>
<result property="courseType" column="courseType"/>
<result property="courseName" column="courseName"/>
</resultMap>
<!-- configuration for the SQL -->
<select id="getCourses" resultMap="courseMap">
<!]>
</select>
</mapper>
五、建立CourseMapper接口和Course类
CourseMapper
package com.mybatis.in;
import java.util.List;
public interface CourseMapper {
public List<Course> getCourses();
}
Course
package com.mybatis.in;
public class Course {
private String courseId;
private String courseName;
private String courseType;
public String getCourseId() {
return courseId;
}
public void setCourseId(String courseId) {
this.courseId = courseId;
}
public String getCourseName() {
return courseName;
}
public void setCourseName(String courseName) {
this.courseName = courseName;
}
public String getCourseType() {
return courseType;
}
public void setCourseType(String courseType) {
this.courseType = courseType;
}
}
完成以上五个步骤，一个简单的Mybatis查询就建立好了，下面我们可以写一段程序测试一下我们上面的配置是否正确
package com.tests;
import java.io.IOException;
import java.util.List;
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 com.mybatis.in.Course;
import com.mybatis.in.CourseMapper;
public class Main {
/**
* @param args
* @throws IOException
*/
public static void main(String[] args) throws IOException {
SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(Resources.getResourceAsStream("mybatis-config.xml"));
SqlSession session = sqlSessionFactory.openSession();
CourseMapper courseMapper =session.getMapper(CourseMapper.class);
List<Course> courses = courseMapper.getCourses();
System.out.println(courses.size());
session.close();
}
}
页:
[1]