Mapper动态代理开发

Posted 2020-11-17 song.yan

1. 在开发的过程中只需要写Dao层的借口，无需写其实现类，实现类有框架自己补充。
2. 框架是根据mapper文件自动补充的，因此需要满足下面四个条件
3. Mapper接口开发需要遵循以下规范：

• • Mapper.xml文件中的namespace与mapper接口的类路径相同。
  • Mapper接口方法名和Mapper.xml中定义的每个statement的id相同
  • Mapper接口方法的输入参数类型和mapper.xml中定义的每个sql 的parameterType的类型相同
  • Mapper接口方法的输出参数类型和mapper.xml中定义的每个sql的resultType的类型相同

1，数据库

create table STUDENT
(
  STU_ID        VARCHAR2(11) not null,
  STU_NAME      VARCHAR2(50),
  STU_BIRTHDATE DATE,
  STU_PHONE     VARCHAR2(50)
)

2，pojo

package com.songyan.pojo;

import java.util.Date;
import java.lang.String;
public class Student {
    private String stuId;
    private String stuName;
    private Date stuBirthdate;
    private String stuPhone;

    public String getStuId() {
        return stuId;
    }

    public void setStuId(String stuId) {
        this.stuId = stuId;
    }

    public String getStuName() {
        return stuName;
    }

    public void setStuName(String stuName) {
        this.stuName = stuName;
    }

    public Date getStuBirthdate() {
        return stuBirthdate;
    }

    public void setStuBirthdate(Date stuBirthdate) {
        this.stuBirthdate = stuBirthdate;
    }

    public String getStuPhone() {
        return stuPhone;
    }

    public void setStuPhone(String stuPhone) {
        this.stuPhone = stuPhone;
    }
    @Override
    public String toString() {
        
        return "student:"+this.stuId+"  "+this.stuName;
    }

}

3，dao

package com.songyan.dao;

import java.util.List;

import com.songyan.pojo.Student;

public interface StudentMapper {
    public void insertStudent(Student student);
    public void deteteStudent(String id);
    public void updateStudent(Student student);
    public List<Student> selectStudent(String id);
}

4，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">
<!-- 设置命名空间 -->
<mapper namespace="com.songyan.dao.StudentMapper">
    <resultMap type="student" id="BaseResultMap">
        <id column="STU_ID" property="stuId" javaType="java.lang.String"
            jdbcType="VARCHAR" />
        <result column="STU_NAME" property="stuName" javaType="java.lang.String"
            jdbcType="VARCHAR" />
        <result column="STU_BIRTHDATE" property="stuBirthdate"
            javaType="java.util.Date" jdbcType="DATE" />
        <result column="STU_PHONE" property="stuPhone" javaType="java.lang.String"
            jdbcType="VARCHAR" />
    </resultMap>
    <select id="selectStudent" parameterType="String"
    resultType="com.songyan.pojo.Student">
        select * from student where STU_ID= #{stuId}
    </select>
    <insert id="insertStudent" parameterType="student" >
        insert into student(STU_ID,STU_NAME,STU_PHONE)
        values(#{stuId},#{stuName},#{stuPhone})
    </insert>
    
    <delete id="deteteStudent" parameterType="String">
        delete from student where STU_ID= #{stuId}
    </delete>
    
    <update id="updateStudent" parameterType="String">
        update student set STU_NAME=#{stuName} where  STU_ID =  #{stuId}
    </update>
</mapper>

5，核心配置文件

<?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">
<configuration>
    <settings>
        <setting name="logImpl" value="LOG4J"/>
    </settings>
    <typeAliases>
        <typeAlias type="com.songyan.pojo.Student" alias="student" />
    </typeAliases>
    <!--配置环境，默认的环境id为oracle -->
    <environments default="oracle">
        <!-- 配置环境为oracle的环境 -->
        <environment id="oracle">
            <!--使用JDBC的事务处理 -->
            <transactionManager type="JDBC" />
            <!--数据库连接池 -->
            <dataSource type="POOLED">
                <property name="driver" value="oracle.jdbc.driver.OracleDriver"></property>
                <property name="url" value="jdbc:oracle:thin:@localhost:1521:inspur"></property>
                <property name="username" value="scott"></property>
                <property name="password" value="tiger"></property>
            </dataSource>
        </environment>
    </environments>
    <!--配置mapper的位置 -->
    <mappers>
        <mapper resource="com/songyan/dao/studentMapper.xml" />
    </mappers>
</configuration>

6，log4j

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p [%t] %c{1}:%L - %m%n
#\\u5728\\u5F00\\u53D1\\u73AF\\u5883\\u4E0B\\u65E5\\u5FD7\\u7EA7\\u522B\\u8981\\u8BBE\\u7F6E\\u6210DEBUG\\uFF0C\\u751F\\u4EA7\\u73AF\\u5883\\u8BBE\\u7F6E\\u6210info\\u6216error
log4j.rootLogger=DEBUG, stdout
#log4j.rootLogger=stdout

7,测试类

package com.songyan.client;

import java.io.IOException;
import java.io.InputStream;
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 org.junit.Test;

import com.songyan.dao.StudentMapper;
import com.songyan.pojo.Student;



public class Client {
@Test 
public void testInsert() throws IOException
{
    //读取配置信息
    String resource="applicationContext.xml";
    //根据配置文件构建sqlsessionFactory
    InputStream in=Resources.getResourceAsStream(resource);
    //通过sqlsessionFactory创建sqlsession
    SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
    SqlSession sqlSession =sqlSessionFactory.openSession(); 
    //创建一个学生对象
    Student student =new Student();
    student.setStuId("1");
    student.setStuName("tom");
    student.setStuPhone("111");
    //获取接口类
    StudentMapper studentMapper=sqlSession.getMapper(StudentMapper.class);
    studentMapper.insertStudent(student);
    //输出结果
    sqlSession.commit();
    sqlSession.close();
}

@Test 
public void testDelete() throws IOException
{
    //读取配置信息
    String resource="applicationContext.xml";
    //根据配置文件构建sqlsessionFactory
    InputStream in=Resources.getResourceAsStream(resource);
    //通过sqlsessionFactory创建sqlsession
    SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
    SqlSession sqlSession =sqlSessionFactory.openSession(); 
    //获取接口类
    StudentMapper studentMapper=sqlSession.getMapper(StudentMapper.class);
    studentMapper.deteteStudent("1");
    sqlSession.commit();
    sqlSession.close();
}


@Test 
public void testUpdate() throws IOException
{
    //读取配置信息
    String resource="applicationContext.xml";
    //根据配置文件构建sqlsessionFactory
    InputStream in=Resources.getResourceAsStream(resource);
    //通过sqlsessionFactory创建sqlsession
    SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
    SqlSession sqlSession =sqlSessionFactory.openSession(); 
    //创建一个学生对象
    Student student =new Student();
    student.setStuId("2");
    student.setStuName("tofm");
    student.setStuPhone("111");
    //获取接口类
    StudentMapper studentMapper=sqlSession.getMapper(StudentMapper.class);
    studentMapper.updateStudent(student);
    
    sqlSession.commit();
    sqlSession.close();
}


@Test 
public void testSelect() throws IOException
{
    //读取配置信息
    String resource="applicationContext.xml";
    //根据配置文件构建sqlsessionFactory
    InputStream in=Resources.getResourceAsStream(resource);
    //通过sqlsessionFactory创建sqlsession
    SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
    SqlSession sqlSession =sqlSessionFactory.openSession(); 
    //获取接口类
    StudentMapper studentMapper=sqlSession.getMapper(StudentMapper.class);

    List<Student> relstu=studentMapper.selectStudent("2");
    System.out.println(relstu.toString());
    //输出结果
    for(Student stu : relstu)
    {
        System.out.println(stu);
    }
    sqlSession.close();
}
}

目录