基于mybatis的增删改查

1.db.properties

mysql.driver=com.mysql.jdbc.Drivermysql.url=jdbc:mysql://127.0.0.1:3306/mybatismysql.username=rootmysql.password=123456oracle.driver=oracle.jdbc.driver.OracleDriveroracle.url=jdbc:oracle:thin:@127.0.0.1:1521:mldnoracle.username=scottoracle.password=tiger

2.StudentMapper.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"><mapper namespace="cn.itcast.app02.Student">    <resultMap type="cn.itcast.app02.Student" id="studentMap">       <id property="id" column="id"></id>       <result property="name" column="name"/>       <result property="sal" column="sal"/>     </resultMap>     <!-- 增加数据-->    <insert id="add" parameterType="cn.itcast.app02.Student">        insert into students(id,name,sal) values(#{id},#{name},#{sal});    </insert>        <!-- 根据id查询 -->    <select id="findById" parameterType="int" resultType="cn.itcast.app02.Student">        select id,name,sal from students where id=#{id};    </select>         <!-- 查询全部数据-->    <select id="findAll" resultType="cn.itcast.app02.Student">        select id,name,sal from students;    </select>         <!-- 更新数据-->     <update id="update" parameterType="cn.itcast.app02.Student">         update students set name=#{name},sal=#{sal} where id=#{id};     </update>          <!-- 更新数据-->     <delete id="delete" parameterType="cn.itcast.app02.Student">         delete from students where id=#{id};     </delete></mapper>

3.StudenDao

package cn.itcast.app02;import java.util.List;import org.apache.ibatis.session.SqlSession;import cn.itcast.util.MybatisUtil;public class StudentDao {//增加数据public void add(Student student) throws Exception{SqlSession sqlSession=null;try{sqlSession=MybatisUtil.getSqlSession();sqlSession.insert(Student.class.getName()+".add",student);sqlSession.commit();}catch(Exception e){e.printStackTrace();//出现异常事物回滚sqlSession.rollback();throw e;}finally{MybatisUtil.closeSqlSession();}}//根据id查询数据public Student findById(int id) throws Exception{SqlSession sqlSession=null;try{sqlSession=MybatisUtil.getSqlSession();Student student=sqlSession.selectOne(Student.class.getName()+".findById",id);sqlSession.commit();return student;}catch(Exception e){e.printStackTrace();//出现异常事物回滚sqlSession.rollback();throw e;}finally{MybatisUtil.closeSqlSession();}}//根据id查询数据public List<Student> findAll() throws Exception{SqlSession sqlSession=null;try{sqlSession=MybatisUtil.getSqlSession();List<Student> studentList=sqlSession.selectList(Student.class.getName()+".findAll");sqlSession.commit();return studentList;}catch(Exception e){e.printStackTrace();//出现异常事物回滚sqlSession.rollback();throw e;}finally{MybatisUtil.closeSqlSession();}}//根据id查询数据public void update(Student student) throws Exception{SqlSession sqlSession=null;try{sqlSession=MybatisUtil.getSqlSession();int i=sqlSession.update(Student.class.getName()+".update",student);sqlSession.commit();}catch(Exception e){e.printStackTrace();//出现异常事物回滚sqlSession.rollback();throw e;}finally{MybatisUtil.closeSqlSession();}}//根据id查询数据public void delete(Student student) throws Exception{SqlSession sqlSession=null;try{sqlSession=MybatisUtil.getSqlSession();sqlSession.delete(Student.class.getName()+".delete",student);sqlSession.commit();}catch(Exception e){e.printStackTrace();//出现异常事物回滚sqlSession.rollback();throw e;}finally{MybatisUtil.closeSqlSession();}}//测试public static void main(String[] args) throws Exception{StudentDao dao=new StudentDao();//dao.add(new Student(1,"能源1",1000D));//dao.add(new Student(2,"能源2",2000D));//dao.add(new Student(3,"能源3",3000D));//dao.add(new Student(4,"能源4",4000D));//dao.add(new Student(5,"能源5",5000D));//Student student=dao.findById(4);/*List<Student> studentList=dao.findAll();for(Student student:studentList){   System.out.println(student.getId()+"\t"+student.getName()+"\t"+student.getSal());}*/Student student=dao.findById(5);dao.delete(student);}}

4.mybatis.xml

<?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>  <properties resource="db.properties"></properties>    <typeAliases>      <typeAlias type="cn.itcast.app01.Student" alias="Student"></typeAlias>  </typeAliases>  <environments default="mysql_developer">     <environment id="mysql_developer">        <transactionManager type="jdbc"></transactionManager>        <dataSource type="pooled">          <property name="driver" value="${mysql.driver}"></property>          <property name="url" value="${mysql.url}"></property>          <property name="username" value="${mysql.username}"></property>          <property name="password" value="${mysql.password}"></property>          </dataSource>     </environment>          <environment id="oracle_developer">        <transactionManager type="jdbc"></transactionManager>        <dataSource type="pooled">          <property name="driver" value="${oracle.driver}"></property>          <property name="url" value="${oracle.url}"></property>          <property name="username" value="${oracle.username}"></property>          <property name="password" value="${oracle.password}"></property>          </dataSource>     </environment>  </environments>    <mappers>     <mapper resource="cn/itcast/app02/StudentMapper.xml"></mapper>  </mappers></configuration>

5.Student

package cn.itcast.app02;public class Student {private Integer id;private String name;private Double sal;public Student(){}public Student(Integer id, String name, Double sal) {super();this.id = id;this.name = name;this.sal = sal;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Double getSal() {return sal;}public void setSal(Double sal) {this.sal = sal;}}