Myabtis的CRUD操作

Mybatis的配置文件：

<?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><!-- 和spring整合后，environments配置将废除 --><environments default="development"><environment id="development"><!-- 使用jdbc事务管理，事务控制由mybatis --><transactionManager type="JDBC"/><!-- 数据库连接池，由mybatis控制 --><dataSource type="POOLED"><property name="driver" value="com.mysql.jdbc.Driver"/><property name="url" value="jdbc:mysql://localhost:3306/数据库名称"/><property name="username" value="用户名"/><property name="password" value="密码"/></dataSource></environment></environments><mappers><mapper resource="mapper/User.xml"/></mappers></configuration>

pojo类

package com.itachi.mybatis.bean;import java.util.Date;public class User {private int id;private String username;private String sex;private Date birthday;private String address;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public String getSex() {return sex;}public void setSex(String sex) {this.sex = sex;}public Date getBirthday() {return birthday;}public void setBirthday(Date birthday) {this.birthday = birthday;}public String getAddress() {return address;}public void setAddress(String address) {this.address = address;}public User() {super();// TODO Auto-generated constructor stub}public User(int id, String username, String sex, Date birthday,String address) {super();this.id = id;this.username = username;this.sex = sex;this.birthday = birthday;this.address = address;}@Overridepublic String toString() {return "User [id=" + id + ", username=" + username + ", sex=" + sex+ ", birthday=" + birthday + ", address=" + address + "]";}}

映射文件：

<?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"><mapper namespace="test"><!-- 在映射文件中配置很多sql语句 --><!-- 需求：通过id查询用户表的记录 --><!-- 通过select执行数据库的查询id：标识映射文件中的sql，将sql语句封装到mappedStatement对象中，所以将id成为statement的idparameterType：指定输入参数的类型，这里指定为int#{}：表示一个占位符#{id}：其中的id表示将接收的输入参数，参数名称就是id，如果输入参数是简单类型，#{}中的参数名可以随意resultType：指定sql输出结果的java对象类型，select指定resultType表示将单条记录映射成java对象 --><select id="findUserById" parameterType="int" resultType="com.itachi.mybatis.bean.User">SELECT * FROM USER WHERE id=#{id}</select><!-- 根据用户名称模糊查询用户信息，可能返回多条记录${}：表示拼接sql串，将接收到的参数内容不加任何修饰拼接在sql中  --><select id="findUserByName" parameterType="java.lang.String" resultType="com.itachi.mybatis.bean.User">SELECT * FROM USER WHERE username LIKE '%${value}%'</select><!-- 添加用户 --><insert id="insertUser">INSERT INTO USER(username, birthday, sex, address) VALUES(#{username}, #{birthday}, #{sex}, #{address})</insert><!-- 修改用户 --><update id="updateUser"  parameterType="com.itachi.mybatis.bean.User">UPDATE USER SET username=#{username}, birthday=#{birthday}, sex=#{sex}, address=#{address} WHERE id=#{id}</update><!-- 删除用户 --><delete id="deleteUser">DELETE FROM USER WHERE id=#{id}</delete></mapper>

CRUD操作：

package com.itachi.mybatis.test;import java.io.IOException;import java.io.InputStream;import java.util.Date;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.itachi.mybatis.bean.User;public class MybatisFirst {@Test public void findUserByIdTest() throws IOException{//配置文件String resource  = "Mybatis-config.xml";//得到配置文件流InputStream is = Resources.getResourceAsStream(resource);//创建会话工厂，传入配置文件信息SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);//通过工厂得到sqlSessionSqlSession sqlSession = sqlSessionFactory.openSession();//通过sqlSession操作数据库//第一个参数：映射文件中statement的id，等于namespace+"."+statement的id//第二个参数：指定和映射文件中所匹配的parameterType类型的参数User user = sqlSession.selectOne("test.findUserById", 1);System.out.println(user);sqlSession.close();}@Testpublic void findUserByNameTest() throws IOException {String resource = "Mybatis-config.xml";InputStream is = Resources.getResourceAsStream(resource);SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);SqlSession sqlSession = sqlSessionFactory.openSession();List<User> list = sqlSession.selectList("test.findUserByName", "小明");for (User user : list) {System.out.println(user);}sqlSession.close();}@Testpublic void insertUserTest() throws IOException {String resource = "Mybatis-config.xml";InputStream is = Resources.getResourceAsStream(resource);SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);SqlSession session = factory.openSession();int insert = session.insert("test.insertUser", new User(-1, "財子紫", "2", new Date(), "美國"));System.out.println(insert);session.commit();session.close();}@Testpublic void updateUserTest() throws IOException {String resource = "Mybatis-config.xml";InputStream is = Resources.getResourceAsStream(resource);SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);SqlSession session = factory.openSession();int update = session.update("test.updateUser", new User(27, "宏宇族", "2", new Date(), "新加坡"));System.out.println(update);session.commit();session.close();}@Testpublic void deleteUserTest() throws IOException {String resource = "Mybatis-config.xml";InputStream is = Resources.getResourceAsStream(resource);SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);SqlSession session = factory.openSession();int delete = session.update("test.deleteUser", 27);System.out.println(delete);session.commit();session.close();}}