mybatis-映射器的CRUD

设计步骤：model、mapper、dao、service、junit单元测试、log4j日志

项目和之前的一样在此只是创建了test和修改了mapper

1.修改映射

1.1修改接口

package com.java1234.mappers;

import java.util.List;

import com.java1234.model.Student;

public interface StudentMapper {

public int add(Student student);

public int update(Student student);

public int delete(Integer id);

public Student findById(Integer id);

public List<Student> find();
}

1.2修改配置

<?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.java1234.mappers.StudentMapper">

<resultMap type="Student" id="StudentResult">
<id property="id" column="id"/>
<result property="name" column="name"/>
<result property="age" column="age"/>
</resultMap>

<insert id="add" parameterType="Student" >
insert into t_student values(null,#{name},#{age})
</insert>

<update id="update" parameterType="Student">
update t_student set name=#{name},age=#{age} where id=#{id}
</update>

<delete id="delete" parameterType="Integer">
delete from t_student where id=#{id}
</delete>

<select id="findById" parameterType="Integer" resultType="Student">
select * from t_student where id=#{id}
</select>

<select id="find" resultMap="StudentResult">
select * from t_student
</select>
</mapper>

2.创建测试环境

package com.java1234.service;

import java.util.List;

import org.apache.ibatis.session.SqlSession;
import org.apache.log4j.Logger;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import com.java1234.mappers.StudentMapper;
import com.java1234.model.Student;
import com.java1234.util.SqlSessionFactoryUtil;

public class StudentTest2 {

private static Logger logger=Logger.getLogger(StudentTest.class);
private SqlSession sqlSession=null;
private StudentMapper studentMapper=null;

/**
* 测试方法前调用
* @throws Exception
*/
@Before
public void setUp() throws Exception {
sqlSession=SqlSessionFactoryUtil.openSession();
studentMapper=sqlSession.getMapper(StudentMapper.class);
}

/**
* 测试方法后调用
* @throws Exception
*/
@After
public void tearDown() throws Exception {
sqlSession.close();
}

@Test
public void testAdd() {
logger.info("添加学生");
Student student=new Student("王五",12);
studentMapper.add(student);
sqlSession.commit();
}

@Test
public void testUpdate(){
logger.info("修改学生");
Student student=new Student(8,"王五2",13);
studentMapper.update(student);
sqlSession.commit();
}

@Test
public void testDelete(){
logger.info("删除学生");
studentMapper.delete(8);
sqlSession.commit();
}

@Test
public void testFindById(){
logger.info("通过ID查找学生");
Student student=studentMapper.findById(1);
System.out.println(student);
}

@Test
public void testFind(){
logger.info("查找所有学生");
List<Student> studentList=studentMapper.find();
for(Student s:studentList){
System.out.println(s);
}
}
}