Student.java
package com.pojo; import java.util.Date; public class Student { int stuid; String stuName; int stuAge; Date stuDate; String stuSex; String stuProfess; String status; String professName; public int getStuid() { return stuid; } public void setStuid(int stuid) { this.stuid = stuid; } public String getStuName() { return stuName; } public void setStuName(String stuName) { this.stuName = stuName; } public int getStuAge() { return stuAge; } public void setStuAge(int stuAge) { this.stuAge = stuAge; } public Date getStuDate() { return stuDate; } public void setStuDate(Date stuDate) { this.stuDate = stuDate; } public String getStuSex() { return stuSex; } public void setStuSex(String stuSex) { this.stuSex = stuSex; } public String getStuProfess() { return stuProfess; } public void setStuProfess(String stuProfess) { this.stuProfess = stuProfess; } public String getStatus() { return status; } public void setStatus(String status) { this.status = status; } public String getProfessName() { return professName; } public void setProfessName(String professName) { this.professName = professName; } }
IStudentDAO.java
使用合理描述参数和SQL语句返回值的接口(比如IStudentDAO.class),这样更简单,更安全的代码,便于和其他优秀框架结合
package com.dao; import com.pojo.Student; public interface IStudentDAO { Student getStudentById(int stuid); void addStudent(Student stu); void delStudent(int id); void updateStudent(int id); }
Student.xml
这里的 id="addStudent" 要和IStudentDAO.java接口中的方法名一致
resultType="student"为实体类在Configuration.xml中配置的别名
<?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.dao.IStudentDAO"> <select id="getStudentById" parameterType="int" resultType="student"> select a.*,b.professname from student a,profess b where a.stuprofess=b.proid and stuid=#{id} </select> <insert id="addStudent" parameterType="com.pojo.Student" keyProperty="stuid"> insert into student values(#{stuid},#{stuName},#{stuAge},#{stuDate},#{stuSex,jdbcType=CHAR},#{stuProfess}) </insert> <delete id="delStudent" parameterType="int"> delete from student where stuid=#{id} </delete> <update id="updateStudent" parameterType="int"> update student set stuName=#{stuName} where stuid=#{id} </update> </mapper>
测试代码
Test.java
package com.pojo; import java.io.IOException; import java.io.Reader; import java.util.Date; 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.dao.IStudentDAO; public class Test { public static void main(String[] args) throws IOException { //读取核心的配置文件 Reader reader = Resources.getResourceAsReader("Configuration.xml"); //创建会话工厂 SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(reader); //数据库会话 SqlSession session = factory.openSession(); //查询一个对象 第一个参数字符串是由Student.xml 中的namespace+id组成 // Student stu = session.selectOne("com.dao.StudentMapper.getStudentById",5); //通过接口的方式 IStudentDAO stuDAO = session.getMapper(IStudentDAO.class); // Student stu = stuDAO.getStudentById(5); // // System.out.println(stu.getStuName()); // System.out.println(stu.getStuDate()); // System.out.println(stu.getProfessName()); //测试新增 Student stu = new Student(); stu.setStuid(16); stu.setStuName("测试新增"); stu.setStuDate(new Date()); // stu.setStuSex("1"); // stu.setStuProfess("1"); // stuDAO.addStudent(stu); //测试删除 stuDAO.delStudent(16); session.commit(); session.close(); } }