Mybatis
1 Mybatis的引言
Mybatis是个基于java语⾔的持久层的框架,主要用来简化数据库的访问操作,内部封装了原来的jdbc代码,替换了原有项目开发中的jdbc技术,他可以自动完成对象与关系的映射(ORM),极度简化了我们的开发,提高开发效率。
2 Jdbc中存在问题
1) 大量的代码冗余 (处理结果集的时候存在大量的冗余)
2) 不能完成数据库和实体的自动转换 (需要手动动封装实体,不能自定封装实体类)
3 Mybatis框架的开发思路
4 Mybatis的环境搭建
4.1 书写连接相关的配置
SqlMapConfig.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">
<!-- mybatis的主配置文件 -->
<configuration>
<!-- 配置环境 -->
<environments default="mysql">
<!-- 配置mysql的环境-->
<environment id="mysql">
<!-- 配置事务的类型-->
<transactionManager type="JDBC"></transactionManager>
<!-- 配置数据源(连接池) -->
<dataSource type="POOLED">
<!-- 配置连接数据库的4个基本信息 -->
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/yxj_mybatis"/>
<property name="username" value="root"/>
<property name="password" value="1234"/>
</dataSource>
</environment>
</environments>
<!-- 指定映射配置文件的位置,映射配置文件指的是每个dao独立的配置文件 -->
<mappers>
<mapper resource="com/yxj/dao/IUserDao.xml"/>
</mappers>
</configuration>
4.2 编写测试类获取连接
MybatisTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.User;
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 java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
* mybatis的入门案例
*/
public class MybatisTest {
/**
* 入门案例
* @param args
*/
public static void main(String[] args)throws Exception {
//1.读取配置文件
InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.创建SqlSessionFactory工厂
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(in);
//3.使用工厂生产SqlSession对象
SqlSession session = factory.openSession();
//4.使用SqlSession创建Dao接口的代理对象
IUserDao userDao = session.getMapper(IUserDao.class);
//5.使用代理对象执行方法
List<User> users = userDao.findAll();
for(User user : users){
System.out.println(user);
}
//6.释放资源
session.close();
in.close();
}
}
4.3 建表
4.4、开发实体类
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable{
private Integer id;
private String username;
private Date birthday;
private String sex;
private String address;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", birthday=" + birthday +
", sex='" + sex + '\'' +
", address='" + address + '\'' +
'}';
}
}
4.5 开发DAO接口
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.User;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*
* 用户的持久层接口
*/
public interface IUserDao {
/**
* 查询所有操作
* @return
*/
List<User> findAll();
}
4.6 编写mapper配置文件
IUserDao.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="com.yxj.dao.IUserDao">
<!--配置查询所有-->
<select id="findAll" resultType="com.yxj.domain.User">
select * from user
</select>
</mapper>
4.7 主配置文件中注册mapper配置文件
4.8 测试DAO中的方法
5 Mybatis中查询
5.1 查询所有数据
5.2.多个参数的查询
6.Mybayxjs中的增删改
6.1 添加
6.2 修改
6.3 删除
6.4 代码事例
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.yxj</groupId>
<artifactId>day02_yxj_mybatisCRUD</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junyxj</groupId>
<artifactId>junyxj</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
</project>
log4j.properties
# Set root category prioryxjy to INFO and yxjs only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and yxjs only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxj_mybatis
jdbc.username=root
jdbc.password=1234
SqlMapConfig.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>
<!-- 配置properties
可以在标签内部配置连接数据库的信息。也可以通过属性引用外部配置文件信息
resource属性: 常用的
用于指定配置文件的位置,是按照类路径的写法来写,并且必须存在于类路径下。
url属性:
是要求按照Url的写法来写地址
URL:Uniform Resource Locator 统一资源定位符。它是可以唯一标识一个资源的位置。
它的写法:
http://localhost:8080/mybatisserver/demo1Servlet
协议 主机 端口 URI
URI:Uniform Resource Identifier 统一资源标识符。它是在应用中可以唯一定位一个资源的。
-->
<!-- <properties resource="jdbcConfig.properties"> </properties>-->
<properties url="file:///D:/IdeaProjects/day02_yxj_01mybatisCRUD/src/main/resources/jdbcConfig.properties">
<!-- <property name="driver" value="com.mysql.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/yxj_mybatis"></property>
<property name="username" value="root"></property>
<property name="password" value="1234"></property>-->
</properties>
<!--使用typeAliases配置别名,它只能配置domain中类的别名 -->
<typeAliases>
<!--typeAlias用于配置别名。type属性指定的是实体类全限定类名。alias属性指定别名,当指定了别名就再区分大小写
<typeAlias type="com.yxj.domain.User" alias="user"></typeAlias>-->
<!-- 用于指定要配置别名的包,当指定之后,该包下的实体类都会注册别名,并且类名就是别名,不再区分大小写-->
<package name="com.yxj.domain"></package>
</typeAliases>
<!--配置环境-->
<environments default="mysql">
<!-- 配置mysql的环境-->
<environment id="mysql">
<!-- 配置事务 -->
<transactionManager type="JDBC"></transactionManager>
<!--配置连接池-->
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</dataSource>
</environment>
</environments>
<!-- 配置映射文件的位置 -->
<mappers>
<!--<mapper resource="com/yxj/dao/IUserDao.xml"></mapper>-->
<!-- package标签是用于指定dao接口所在的包,当指定了之后就不需要在写mapper以及resource或者class了 -->
<package name="com.yxj.dao"></package>
</mappers>
</configuration>
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable {
private Integer userId;
private String userName;
private String userAddress;
private String userSex;
private Date userBirthday;
public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getUserAddress() {
return userAddress;
}
public void setUserAddress(String userAddress) {
this.userAddress = userAddress;
}
public String getUserSex() {
return userSex;
}
public void setUserSex(String userSex) {
this.userSex = userSex;
}
public Date getUserBirthday() {
return userBirthday;
}
public void setUserBirthday(Date userBirthday) {
this.userBirthday = userBirthday;
}
@Override
public String toString() {
return "User{" +
"userId=" + userId +
", userName='" + userName + '\'' +
", userAddress='" + userAddress + '\'' +
", userSex='" + userSex + '\'' +
", userBirthday=" + userBirthday +
'}';
}
}
QueryVo.java
package com.yxj.domain;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class QueryVo {
private User user;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
}
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.QueryVo;
import com.yxj.domain.User;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*
* 用户的持久层接口
*/
public interface IUserDao {
/**
* 查询所有用户
* @return
*/
List<User> findAll();
/**
* 保存用户
* @param user
*/
void saveUser(User user);
/**
* 更新用户
* @param user
*/
void updateUser(User user);
/**
* 根据Id删除用户
* @param userId
*/
void deleteUser(Integer userId);
/**
* 根据id查询用户信息
* @param userId
* @return
*/
User findById(Integer userId);
/**
* 根据名称模糊查询用户信息
* @param username
* @return
*/
List<User> findByName(String username);
/**
* 查询总用户数
* @return
*/
int findTotal();
/**
* 根据queryVo中的条件查询用户
* @param vo
* @return
*/
List<User> findUserByVo(QueryVo vo);
}
IUserDao.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="com.yxj.dao.IUserDao">
<!-- 配置 查询结果的列名和实体类的属性名的对应关系 -->
<resultMap id="userMap" type="uSeR">
<!-- 主键字段的对应 -->
<id property="userId" column="id"></id>
<!--非主键字段的对应-->
<result property="userName" column="username"></result>
<result property="userAddress" column="address"></result>
<result property="userSex" column="sex"></result>
<result property="userBirthday" column="birthday"></result>
</resultMap>
<!-- 查询所有 -->
<select id="findAll" resultMap="userMap">
<!--select id as userId,username as userName,address as userAddress,sex as userSex,birthday as userBirthday from user;-->
select * from user;
</select>
<!-- 保存用户 -->
<insert id="saveUser" parameterType="user">
<!-- 配置插入操作后,获取插入数据的id -->
<selectKey keyProperty="userId" keyColumn="id" resultType="int" order="AFTER">
select last_insert_id();
</selectKey>
insert into user(username,address,sex,birthday)values(#{userName},#{userAddress},#{userSex},#{userBirthday});
</insert>
<!-- 更新用户 -->
<update id="updateUser" parameterType="USER">
update user set username=#{userName},address=#{userAddress},sex=#{userAex},birthday=#{userBirthday} where id=#{userId}
</update>
<!-- 删除用户-->
<delete id="deleteUser" parameterType="java.lang.Integer">
delete from user where id = #{uid}
</delete>
<!-- 根据id查询用户 -->
<select id="findById" parameterType="INT" resultMap="userMap">
select * from user where id = #{uid}
</select>
<!-- 根据名称模糊查询 -->
<select id="findByName" parameterType="string" resultMap="userMap">
select * from user where username like #{name} # 开发中用这一种,因为可以防止sql注入问题
<!-- select * from user where username like '%${value}%' # 如果是这一种。那么value固定不可以变-->
<!-- select * from user where username like concat('%',#{value},'%')-->
</select>
<!-- 获取用户的总记录条数 -->
<select id="findTotal" resultType="int">
select count(id) from user;
</select>
<!-- 根据q ueryVo的条件查询用户 -->
<select id="findUserByVo" parameterType="com.yxj.domain.QueryVo" resultMap="userMap">
select * from user where username like #{user.username}
</select>
</mapper>
MybatisTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.QueryVo;
import com.yxj.domain.User;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.Date;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*
* 测试mybatis的crud操作
*/
public class MybatisTest {
private InputStream in;
private SqlSession sqlSession;
private IUserDao userDao;
@Before//用于在测试方法执行之前执行
public void inyxj()throws Exception{
//1.读取配置文件,生成字节输入流
in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.获取SqlSessionFactory
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
//3.获取SqlSession对象
sqlSession = factory.openSession();
//4.获取dao的代理对象
userDao = sqlSession.getMapper(IUserDao.class);
}
@After//用于在测试方法执行之后执行
public void destroy()throws Exception{
//提交事务
sqlSession.commit();
//6.释放资源
sqlSession.close();
in.close();
}
/**
* 测试查询所有
*/
@Test
public void testFindAll(){
//5.执行查询所有方法
List<User> users = userDao.findAll();
for(User user : users){
System.out.println(user);
}
}
/**
* 测试保存操作
*/
@Test
public void testSave(){
User user = new User();
user.setUserName("modify User property");
user.setUserAddress("北京市顺义区");
user.setUserSex("男");
user.setUserBirthday(new Date());
System.out.println("保存操作之前:"+user);
//5.执行保存方法
userDao.saveUser(user);
System.out.println("保存操作之后:"+user);
}
/**
* 测试更新操作
*/
@Test
public void testUpdate(){
User user = new User();
user.setUserId(50);
user.setUserName("mybastis update user");
user.setUserAddress("北京市顺义区");
user.setUserSex("女");
user.setUserBirthday(new Date());
//5.执行保存方法
userDao.updateUser(user);
}
/**
* 测试删除操作
*/
@Test
public void testDelete(){
//5.执行删除方法
userDao.deleteUser(48);
}
/**
* 测试删除操作
*/
@Test
public void testFindOne(){
//5.执行查询一个方法
User user = userDao.findById(50);
System.out.println(user);
}
/**
* 测试模糊查询操作
*/
@Test
public void testFindByName(){
//5.执行查询一个方法
List<User> users = userDao.findByName("%王%");
// List<User> users = userDao.findByName("王");
for(User user : users){
System.out.println(user);
}
}
/**
* 测试查询总记录条数
*/
@Test
public void testFindTotal(){
//5.执行查询一个方法
int count = userDao.findTotal();
System.out.println(count);
}
/**
* 测试使用QueryVo作为查询条件
*/
@Test
public void testFindByVo(){
QueryVo vo = new QueryVo();
User user = new User();
user.setUserName("%王%");
vo.setUser(user);
//5.执行查询一个方法
List<User> users = userDao.findUserByVo(vo);
for(User u : users){
System.out.println(u);
}
}
}
6.5 注解开发(增删查改)
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.yxj</groupId>
<artifactId>day04_yxj_03annotation_mybatis</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junyxj</groupId>
<artifactId>junyxj</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
</project>
jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxj_mybatis
jdbc.username=root
jdbc.password=1234
log4j.properties
# Set root category prioryxjy to INFO and yxjs only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and yxjs only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
SqlMapConfig.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>
<!-- 引入外部配置文件-->
<properties resource="jdbcConfig.properties"></properties>
<!--配置别名-->
<typeAliases>
<package name="com.yxj.domain"></package>
</typeAliases>
<!-- 配置环境-->
<environments default="mysql">
<environment id="mysql">
<transactionManager type="JDBC"></transactionManager>
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</dataSource>
</environment>
</environments>
<!-- 指定带有注解的dao接口所在位置 -->
<mappers>
<mapper class="com.yxj.dao.IUserDao"></mapper>
</mappers>
</configuration>
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable{
private Integer id;
private String username;
private String address;
private String sex;
private Date birthday;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
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;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", address='" + address + '\'' +
", sex='" + sex + '\'' +
", birthday=" + birthday +
'}';
}
}
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.User;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
* 在mybatis中针对,CRUD一共有四个注解
* @Select @Insert @Update @Delete
*/
public interface IUserDao {
/**
* 查询所有用户
* @return
*/
@Select("select * from user")
List<User> findAll();
/**
* 保存用户
* @param user
*/
@Insert("insert into user(username,address,sex,birthday)values(#{username},#{address},#{sex},#{birthday})")
void saveUser(User user);
/**
* 更新用户
* @param user
*/
@Update("update user set username=#{username},sex=#{sex},birthday=#{birthday},address=#{address} where id=#{id}")
void updateUser(User user);
/**
* 删除用户
* @param userId
*/
@Delete("delete from user where id=#{id} ")
void deleteUser(Integer userId);
/**
* 根据id查询用户
* @param userId
* @return
*/
@Select("select * from user where id=#{id} ")
User findById(Integer userId);
/**
* 根据用户名称模糊查询
* @param username
* @return
*/
// @Select("select * from user where username like #{username} ")
@Select("select * from user where username like '%${value}%' ")
List<User> findUserByName(String username);
/**
* 查询总用户数量
* @return
*/
@Select("select count(*) from user ")
int findTotalUser();
}
AnnotationCRUDTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.User;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.Date;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class AnnotationCRUDTest {
private InputStream in;
private SqlSessionFactory factory;
private SqlSession session;
private IUserDao userDao;
@Before
public void inyxj()throws Exception{
in = Resources.getResourceAsStream("SqlMapConfig.xml");
factory = new SqlSessionFactoryBuilder().build(in);
session = factory.openSession();
userDao = session.getMapper(IUserDao.class);
}
@After
public void destroy()throws Exception{
session.commit();
session.close();
in.close();
}
@Test
public void testSave(){
User user = new User();
user.setUsername("mybatis annotation");
user.setAddress("北京市昌平区");
userDao.saveUser(user);
}
@Test
public void testUpdate(){
User user = new User();
user.setId(57);
user.setUsername("mybatis annotation update");
user.setAddress("北京市海淀区");
user.setSex("男");
user.setBirthday(new Date());
userDao.updateUser(user);
}
@Test
public void testDelete(){
userDao.deleteUser(51);
}
@Test
public void testFindOne(){
User user = userDao.findById(57);
System.out.println(user);
}
@Test
public void testFindByName(){
// List<User> users = userDao.findUserByName("%mybatis%");
List<User> users = userDao.findUserByName("mybatis");
for(User user : users){
System.out.println(user);
}
}
@Test
public void testFindTotal(){
int total = userDao.findTotalUser();
System.out.println(total);
}
}
7 Mybatis工具类封装
8 添加修改细节
注意: Mybatis执行插入,修改时不允许出现空值,因此在插入修改时,想要使某个列的值可以为空,必须加jdbcType属性
8.1 添加修改细节
8.2 执行添加时
9 全部的jdbcType属性
10 显示执行sql语句
引入log4j.properties
log4j.rootLogger=DEBUG, Console //根⽇志
log4j.appender.Console=org.apache.log4j.ConsoleAppender //控制台展示
log4j.appender.Console.layout=org.apache.log4j.PatternLayout //打印⽅式
log4j.appender.Console.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n //⽇
志格式
log4j.logger.com.yxj.dao=DEBUG
注意:
1.log4j中存在两种日志。一种是项目中的根日志,二种种是项目中子日志
2.一般在项目中开启子日志即可
3. 日志级别: ERROR、WARN、INFO、DEBUG、TRACE
11 Mybatis中的别名
声明别名
使用别名
12 MyBatis中动态Sql
12.1 sql复用标签
12.2 if标签 动态拼接sql
12.3 where标签
12.4 choose when otherwise标签
12.5 set标签
12.6 trim标签
12.7 foreach遍历标签
12.8 代码事例
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.yxj</groupId>
<artifactId>day03_yxj_02dynamicSQL</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junyxj</groupId>
<artifactId>junyxj</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
</project>
SqlMapConfig.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>
<!-- 配置properties-->
<properties resource="jdbcConfig.properties"></properties>
<!--使用typeAliases配置别名,它只能配置domain中类的别名 -->
<typeAliases>
<package name="com.yxj.domain"></package>
</typeAliases>
<!--配置环境-->
<environments default="mysql">
<!-- 配置mysql的环境-->
<environment id="mysql">
<!-- 配置事务 -->
<transactionManager type="JDBC"></transactionManager>
<!--配置连接池-->
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</dataSource>
</environment>
</environments>
<!-- 配置映射文件的位置 -->
<mappers>
<package name="com.yxj.dao"></package>
</mappers>
</configuration>
log4j.properties
# Set root category prioryxjy to INFO and yxjs only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and yxjs only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{
ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{
ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxj_mybatis
jdbc.username=root
jdbc.password=1234
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable {
private Integer userId;
private String userName;
private String userAddress;
private String userSex;
private Date userBirthday;
public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getUserAddress() {
return userAddress;
}
public void setUserAddress(String userAddress) {
this.userAddress = userAddress;
}
public String getUserSex() {
return userSex;
}
public void setUserSex(String userSex) {
this.userSex = userSex;
}
public Date getUserBirthday() {
return userBirthday;
}
public void setUserBirthday(Date userBirthday) {
this.userBirthday = userBirthday;
}
@Override
public String toString() {
return "User{" +
"userId=" + userId +
", userName='" + userName + '\'' +
", userAddress='" + userAddress + '\'' +
", userSex='" + userSex + '\'' +
", userBirthday=" + userBirthday +
'}';
}
}
QueryVo.java
package com.yxj.domain;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class QueryVo {
private User user;
private List<Integer> ids;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public List<Integer> getIds() {
return ids;
}
public void setIds(List<Integer> ids) {
this.ids = ids;
}
}
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.QueryVo;
import com.yxj.domain.User;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*
* 用户的持久层接口
*/
public interface IUserDao {
/**
* 查询所有用户
* @return
*/
List<User> findAll();
/**
* 根据id查询用户信息
* @param userId
* @return
*/
User findById(Integer userId);
/**
* 根据名称模糊查询用户信息
* @param username
* @return
*/
List<User> findByName(String username);
/**
* 根据queryVo中的条件查询用户
* @param vo
* @return
*/
List<User> findUserByVo(QueryVo vo);
/**
* 根据传入参数条件
* @param user 查询的条件:有可能有用户名,有可能有性别,也有可能有地址,还有可能是都有
* @return
*/
List<User> findUserByCondyxjion(User user);
/**
* 根据queryvo中提供的id集合,查询用户信息
* @param vo
* @return
*/
List<User> findUserInIds(QueryVo vo);
}
IUserDao.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="com.yxj.dao.IUserDao">
<!-- 配置 查询结果的列名和实体类的属性名的对应关系 -->
<resultMap id="userMap" type="uSeR">
<!-- 主键字段的对应 -->
<id property="userId" column="id"></id>
<!--非主键字段的对应-->
<result property="userName" column="username"></result>
<result property="userAddress" column="address"></result>
<result property="userSex" column="sex"></result>
<result property="userBirthday" column="birthday"></result>
</resultMap>
<!-- 了解的内容:抽取重复的sql语句-->
<sql id="defaultUser">
select * from user
</sql>
<!-- 查询所有 -->
<select id="findAll" resultMap="userMap">
<include refid="defaultUser"></include>
</select>
<!-- 根据id查询用户 -->
<select id="findById" parameterType="INT" resultMap="userMap">
select * from user where id = #{
uid}
</select>
<!-- 根据名称模糊查询 -->
<select id="findByName" parameterType="string" resultMap="userMap">
select * from user where username like #{
name}
</select>
<!-- 根据queryVo的条件查询用户 -->
<select id="findUserByVo" parameterType="com.yxj.domain.QueryVo" resultMap="userMap">
select * from user where username like #{
user.userName}
</select>
<!-- 根据条件查询
<select id="findUserByCondyxjion" resultMap="userMap" parameterType="user">
select * from user where 1=1
<if test="userName != null">
and username = #{
userName}
</if>
<if test="userSex != null">
and sex = #{
userSex}
</if>
</select>-->
<select id="findUserByCondyxjion" resultMap="userMap" parameterType="user">
select * from user
<where>
<if test="userName != null">
and username = #{
userName}
</if>
<if test="userSex != null">
and sex = #{
userSex}
</if>
</where>
</select>
<!-- 根据queryvo中的Id集合实现查询用户列表 -->
<select id="findUserInIds" resultMap="userMap" parameterType="queryvo">
<include refid="defaultUser"></include>
<where>
<if test="ids != null and ids.size()>0">
<foreach collection="ids" open="and id in (" close=")" yxjem="uid" separator=",">
#{
uid}
</foreach>
</if>
</where>
</select>
</mapper>
13 Mybatis处理一对一关联关系
13.1 数据库
13.2 实体类
13.3 根据用户查找用户的身份信息
14 Mybatis处理一对多关联关系
14.1 数据库模型
14.2 实体类实现
14.3 通过部门找员工
14.4 通过员工找部门
14.5 代码事例
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.yxj</groupId>
<artifactId>day03_yxj_03one2many</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junyxj</groupId>
<artifactId>junyxj</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
</project>
log4j.properties
# Set root category prioryxjy to INFO and yxjs only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and yxjs only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxj_mybatis
jdbc.username=root
jdbc.password=1234
SqlMapConfig.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>
<!-- 配置properties-->
<properties resource="jdbcConfig.properties"></properties>
<!--使用typeAliases配置别名,它只能配置domain中类的别名 -->
<typeAliases>
<package name="com.yxj.domain"></package>
</typeAliases>
<!--配置环境-->
<environments default="mysql">
<!-- 配置mysql的环境-->
<environment id="mysql">
<!-- 配置事务 -->
<transactionManager type="JDBC"></transactionManager>
<!--配置连接池-->
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</dataSource>
</environment>
</environments>
<!-- 配置映射文件的位置 -->
<mappers>
<package name="com.yxj.dao"></package>
</mappers>
</configuration>
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable {
private Integer id;
private String username;
private String address;
private String sex;
private Date birthday;
//一对多关系映射:主表实体应该包含从表实体的集合引用
private List<Account> accounts;
public List<Account> getAccounts() {
return accounts;
}
public void setAccounts(List<Account> accounts) {
this.accounts = accounts;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
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;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", address='" + address + '\'' +
", sex='" + sex + '\'' +
", birthday=" + birthday +
'}';
}
}
Account.java
package com.yxj.domain;
import java.io.Serializable;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class Account implements Serializable {
private Integer id;
private Integer uid;
private Double money;
//从表实体应该包含一个主表实体的对象引用
private User user;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getUid() {
return uid;
}
public void setUid(Integer uid) {
this.uid = uid;
}
public Double getMoney() {
return money;
}
public void setMoney(Double money) {
this.money = money;
}
@Override
public String toString() {
return "Account{" +
"id=" + id +
", uid=" + uid +
", money=" + money +
'}';
}
}
AccountUser.java
package com.yxj.domain;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class AccountUser extends Account {
private String username;
private String address;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return super.toString()+" AccountUser{" +
"username='" + username + '\'' +
", address='" + address + '\'' +
'}';
}
}
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.User;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*
* 用户的持久层接口
*/
public interface IUserDao {
/**
* 查询所有用户,同时获取到用户下所有账户的信息
* @return
*/
List<User> findAll();
/**
* 根据id查询用户信息
* @param userId
* @return
*/
User findById(Integer userId);
}
IUserDao.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="com.yxj.dao.IUserDao">
<!-- 定义User的resultMap-->
<resultMap id="userAccountMap" type="user">
<id property="id" column="id"></id>
<result property="username" column="username"></result>
<result property="address" column="address"></result>
<result property="sex" column="sex"></result>
<result property="birthday" column="birthday"></result>
<!-- 配置user对象中accounts集合的映射 -->
<collection property="accounts" ofType="account">
<id column="aid" property="id"></id>
<result column="uid" property="uid"></result>
<result column="money" property="money"></result>
</collection>
</resultMap>
<!-- 查询所有 -->
<select id="findAll" resultMap="userAccountMap">
select * from user u left outer join account a on u.id = a.uid
</select>
<!-- 根据id查询用户 -->
<select id="findById" parameterType="INT" resultType="user">
select * from user where id = #{
uid}
</select>
</mapper>
IAccountDao.java
package com.yxj.dao;
import com.yxj.domain.Account;
import com.yxj.domain.AccountUser;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public interface IAccountDao {
/**
* 查询所有账户,同时还要获取到当前账户的所属用户信息
* @return
*/
List<Account> findAll();
/**
* 查询所有账户,并且带有用户名称和地址信息
* @return
*/
List<AccountUser> findAllAccount();
}
IAccountDao.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="com.yxj.dao.IAccountDao">
<!-- 定义封装account和user的resultMap -->
<resultMap id="accountUserMap" type="account">
<id property="id" column="aid"></id>
<result property="uid" column="uid"></result>
<result property="money" column="money"></result>
<!-- 一对一的关系映射:配置封装user的内容-->
<association property="user" column="uid" javaType="user">
<id property="id" column="id"></id>
<result column="username" property="username"></result>
<result column="address" property="address"></result>
<result column="sex" property="sex"></result>
<result column="birthday" property="birthday"></result>
</association>
</resultMap>
<!-- 查询所有 -->
<select id="findAll" resultMap="accountUserMap">
select u.*,a.id as aid,a.uid,a.money from account a , user u where u.id = a.uid;
</select>
<!--查询所有账户同时包含用户名和地址信息-->
<select id="findAllAccount" resultType="accountuser">
select a.*,u.username,u.address from account a , user u where u.id = a.uid;
</select>
</mapper>
UserTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.User;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class UserTest {
private InputStream in;
private SqlSession sqlSession;
private IUserDao userDao;
@Before//用于在测试方法执行之前执行
public void inyxj()throws Exception{
//1.读取配置文件,生成字节输入流
in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.获取SqlSessionFactory
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
//3.获取SqlSession对象
sqlSession = factory.openSession(true);
//4.获取dao的代理对象
userDao = sqlSession.getMapper(IUserDao.class);
}
@After//用于在测试方法执行之后执行
public void destroy()throws Exception{
//提交事务
// sqlSession.commit();
//6.释放资源
sqlSession.close();
in.close();
}
/**
* 测试查询所有
*/
@Test
public void testFindAll(){
List<User> users = userDao.findAll();
for(User user : users){
System.out.println("-----每个用户的信息------");
System.out.println(user);
System.out.println(user.getAccounts());
}
}
}
AccountTest.java
package com.yxj.test;
import com.yxj.dao.IAccountDao;
import com.yxj.domain.Account;
import com.yxj.domain.AccountUser;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class AccountTest {
private InputStream in;
private SqlSession sqlSession;
private IAccountDao accountDao;
@Before//用于在测试方法执行之前执行
public void inyxj()throws Exception{
//1.读取配置文件,生成字节输入流
in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.获取SqlSessionFactory
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
//3.获取SqlSession对象
sqlSession = factory.openSession(true);
//4.获取dao的代理对象
accountDao = sqlSession.getMapper(IAccountDao.class);
}
@After//用于在测试方法执行之后执行
public void destroy()throws Exception{
//提交事务
// sqlSession.commit();
//6.释放资源
sqlSession.close();
in.close();
}
/**
* 测试查询所有
*/
@Test
public void testFindAll(){
List<Account> accounts = accountDao.findAll();
for(Account account : accounts){
System.out.println("--------每个account的信息------------");
System.out.println(account);
System.out.println(account.getUser());
}
}
/**
* 测试查询所有账户,同时包含用户名称和地址
*/
@Test
public void testFindAllAccountUser(){
List<AccountUser> aus = accountDao.findAllAccount();
for(AccountUser au : aus){
System.out.println(au);
}
}
}
14.6 注解开发
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.yxj</groupId>
<artifactId>day04_yxj_04annoOne2Many</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junyxj</groupId>
<artifactId>junyxj</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
</project>
jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxj_mybatis
jdbc.username=root
jdbc.password=1234
SqlMapConfig.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>
<!-- 引入外部配置文件-->
<properties resource="jdbcConfig.properties"></properties>
<!--配置开启二级缓存-->
<settings>
<setting name="cacheEnabled" value="true"/>
</settings>
<!--配置别名-->
<typeAliases>
<package name="com.yxj.domain"></package>
</typeAliases>
<!-- 配置环境-->
<environments default="mysql">
<environment id="mysql">
<transactionManager type="JDBC"></transactionManager>
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</dataSource>
</environment>
</environments>
<!-- 指定带有注解的dao接口所在位置 -->
<mappers>
<package name="com.yxj.dao"></package>
</mappers>
</configuration>
log4j.properties
# Set root category prioryxjy to INFO and yxjs only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and yxjs only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
Account.java
package com.yxj.domain;
import java.io.Serializable;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class Account implements Serializable {
private Integer id;
private Integer uid;
private Double money;
//多对一(mybatis中称之为一对一)的映射:一个账户只能属于一个用户
private User user;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getUid() {
return uid;
}
public void setUid(Integer uid) {
this.uid = uid;
}
public Double getMoney() {
return money;
}
public void setMoney(Double money) {
this.money = money;
}
@Override
public String toString() {
return "Account{" +
"id=" + id +
", uid=" + uid +
", money=" + money +
'}';
}
}
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable{
private Integer userId;
private String userName;
private String userAddress;
private String userSex;
private Date userBirthday;
//一对多关系映射:一个用户对应多个账户
private List<Account> accounts;
public List<Account> getAccounts() {
return accounts;
}
public void setAccounts(List<Account> accounts) {
this.accounts = accounts;
}
public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getUserAddress() {
return userAddress;
}
public void setUserAddress(String userAddress) {
this.userAddress = userAddress;
}
public String getUserSex() {
return userSex;
}
public void setUserSex(String userSex) {
this.userSex = userSex;
}
public Date getUserBirthday() {
return userBirthday;
}
public void setUserBirthday(Date userBirthday) {
this.userBirthday = userBirthday;
}
@Override
public String toString() {
return "User{" +
"userId=" + userId +
", userName='" + userName + '\'' +
", userAddress='" + userAddress + '\'' +
", userSex='" + userSex + '\'' +
", userBirthday=" + userBirthday +
'}';
}
}
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.User;
import org.apache.ibatis.annotations.*;
import org.apache.ibatis.mapping.FetchType;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
* 在mybatis中针对,CRUD一共有四个注解
* @Select @Insert @Update @Delete
*/
@CacheNamespace(blocking = true)
public interface IUserDao {
/**
* 查询所有用户
* @return
*/
@Select("select * from user")
@Results(id="userMap",value={
@Result(id=true,column = "id",property = "userId"),
@Result(column = "username",property = "userName"),
@Result(column = "address",property = "userAddress"),
@Result(column = "sex",property = "userSex"),
@Result(column = "birthday",property = "userBirthday"),
@Result(property = "accounts",column = "id",
many = @Many(select = "com.yxj.dao.IAccountDao.findAccountByUid",
fetchType = FetchType.LAZY))
})
List<User> findAll();
/**
* 根据id查询用户
* @param userId
* @return
*/
@Select("select * from user where id=#{id} ")
@ResultMap("userMap")
User findById(Integer userId);
/**
* 根据用户名称模糊查询
* @param username
* @return
*/
@Select("select * from user where username like #{username} ")
@ResultMap("userMap")
List<User> findUserByName(String username);
}
IAccountDao.java
package com.yxj.dao;
import com.yxj.domain.Account;
import org.apache.ibatis.annotations.One;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.mapping.FetchType;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public interface IAccountDao {
/**
* 查询所有账户,并且获取每个账户所属的用户信息
* @return
*/
@Select("select * from account")
@Results(id="accountMap",value = {
@Result(id=true,column = "id",property = "id"),
@Result(column = "uid",property = "uid"),
@Result(column = "money",property = "money"),
@Result(property = "user",column = "uid",one=@One(select="com.yxj.dao.IUserDao.findById",fetchType= FetchType.EAGER))
})
List<Account> findAll();
/**
* 根据用户id查询账户信息
* @param userId
* @return
*/
@Select("select * from account where uid = #{userId}")
List<Account> findAccountByUid(Integer userId);
}
AccountTest.java
package com.yxj.test;
import com.yxj.dao.IAccountDao;
import com.yxj.domain.Account;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class AccountTest {
private InputStream in;
private SqlSessionFactory factory;
private SqlSession session;
private IAccountDao accountDao;
@Before
public void inyxj()throws Exception{
in = Resources.getResourceAsStream("SqlMapConfig.xml");
factory = new SqlSessionFactoryBuilder().build(in);
session = factory.openSession();
accountDao = session.getMapper(IAccountDao.class);
}
@After
public void destroy()throws Exception{
session.commit();
session.close();
in.close();
}
@Test
public void testFindAll(){
List<Account> accounts = accountDao.findAll();
for(Account account : accounts){
System.out.println("----每个账户的信息-----");
System.out.println(account);
System.out.println(account.getUser());
}
}
}
AnnotationCRUDTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.User;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class AnnotationCRUDTest {
private InputStream in;
private SqlSessionFactory factory;
private SqlSession session;
private IUserDao userDao;
@Before
public void inyxj()throws Exception{
in = Resources.getResourceAsStream("SqlMapConfig.xml");
factory = new SqlSessionFactoryBuilder().build(in);
session = factory.openSession();
userDao = session.getMapper(IUserDao.class);
}
@After
public void destroy()throws Exception{
session.commit();
session.close();
in.close();
}
@Test
public void testFindAll(){
List<User> users = userDao.findAll();
// for(User user : users){
// System.out.println("---每个用户的信息----");
// System.out.println(user);
// System.out.println(user.getAccounts());
// }
}
@Test
public void testFindOne(){
User user = userDao.findById(57);
System.out.println(user);
}
@Test
public void testFindByName(){
List<User> users = userDao.findUserByName("%mybatis%");
for(User user : users){
System.out.println(user);
}
}
}
SecondLevelCatchTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.User;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class SecondLevelCatchTest {
private InputStream in;
private SqlSessionFactory factory;
@Before
public void inyxj()throws Exception{
in = Resources.getResourceAsStream("SqlMapConfig.xml");
factory = new SqlSessionFactoryBuilder().build(in);
}
@After
public void destroy()throws Exception{
in.close();
}
@Test
public void testFindOne(){
SqlSession session = factory.openSession();
IUserDao userDao = session.getMapper(IUserDao.class);
User user = userDao.findById(57);
System.out.println(user);
session.close();//释放一级缓存
SqlSession session1 = factory.openSession();//再次打开session
IUserDao userDao1 = session1.getMapper(IUserDao.class);
User user1 = userDao1.findById(57);
System.out.println(user1);
session1.close();
}
}
15 Mybatis处理多对多关联关系
多对多在数据库的设计里也是使用两个一对多实现的
实体类在开发时两边都是集合类型的关系属性
mapper文件在维护时都使用 <collection 标签>
15.1 代码例子
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.yxj</groupId>
<artifactId>day03_yxj_04many2many</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junyxj</groupId>
<artifactId>junyxj</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
</project>
log4j.properties
# Set root category prioryxjy to INFO and yxjs only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and yxjs only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{
ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{
ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxj_mybatis
jdbc.username=root
jdbc.password=1234
SqlMapConfig.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>
<!-- 配置properties-->
<properties resource="jdbcConfig.properties"></properties>
<!--使用typeAliases配置别名,它只能配置domain中类的别名 -->
<typeAliases>
<package name="com.yxj.domain"></package>
</typeAliases>
<!--配置环境-->
<environments default="mysql">
<!-- 配置mysql的环境-->
<environment id="mysql">
<!-- 配置事务 -->
<transactionManager type="JDBC"></transactionManager>
<!--配置连接池-->
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</dataSource>
</environment>
</environments>
<!-- 配置映射文件的位置 -->
<mappers>
<package name="com.yxj.dao"></package>
</mappers>
</configuration>
User.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.Date;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class User implements Serializable {
private Integer id;
private String username;
private String address;
private String sex;
private Date birthday;
//多对多的关系映射:一个用户可以具备多个角色
private List<Role> roles;
public List<Role> getRoles() {
return roles;
}
public void setRoles(List<Role> roles) {
this.roles = roles;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
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;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", address='" + address + '\'' +
", sex='" + sex + '\'' +
", birthday=" + birthday +
'}';
}
}
Role.java
package com.yxj.domain;
import java.io.Serializable;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class Role implements Serializable {
private Integer roleId;
private String roleName;
private String roleDesc;
//多对多的关系映射:一个角色可以赋予多个用户
private List<User> users;
public List<User> getUsers() {
return users;
}
public void setUsers(List<User> users) {
this.users = users;
}
public Integer getRoleId() {
return roleId;
}
public void setRoleId(Integer roleId) {
this.roleId = roleId;
}
public String getRoleName() {
return roleName;
}
public void setRoleName(String roleName) {
this.roleName = roleName;
}
public String getRoleDesc() {
return roleDesc;
}
public void setRoleDesc(String roleDesc) {
this.roleDesc = roleDesc;
}
@Override
public String toString() {
return "Role{" +
"roleId=" + roleId +
", roleName='" + roleName + '\'' +
", roleDesc='" + roleDesc + '\'' +
'}';
}
}
IUserDao.java
package com.yxj.dao;
import com.yxj.domain.User;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*
* 用户的持久层接口
*/
public interface IUserDao {
/**
* 查询所有用户,同时获取到用户下所有账户的信息
* @return
*/
List<User> findAll();
/**
* 根据id查询用户信息
* @param userId
* @return
*/
User findById(Integer userId);
}
IUserDao.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="com.yxj.dao.IUserDao">
<!-- 定义User的resultMap-->
<resultMap id="userMap" type="user">
<id property="id" column="id"></id>
<result property="username" column="username"></result>
<result property="address" column="address"></result>
<result property="sex" column="sex"></result>
<result property="birthday" column="birthday"></result>
<!-- 配置角色集合的映射 -->
<collection property="roles" ofType="role">
<id property="roleId" column="rid"></id>
<result property="roleName" column="role_name"></result>
<result property="roleDesc" column="role_desc"></result>
</collection>
</resultMap>
<!-- 查询所有 -->
<select id="findAll" resultMap="userMap">
select u.*,r.id as rid,r.role_name,r.role_desc from user u
left outer join user_role ur on u.id = ur.uid
left outer join role r on r.id = ur.rid
</select>
<!-- 根据id查询用户 -->
<select id="findById" parameterType="INT" resultType="user">
select * from user where id = #{uid}
</select>
</mapper>
IRoleDao.java
package com.yxj.dao;
import com.yxj.domain.Role;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public interface IRoleDao {
/**
* 查询所有角色
* @return
*/
List<Role> findAll();
}
IRoleDao.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="com.yxj.dao.IRoleDao">
<!--定义role表的ResultMap-->
<resultMap id="roleMap" type="role">
<id property="roleId" column="rid"></id>
<result property="roleName" column="role_name"></result>
<result property="roleDesc" column="role_desc"></result>
<collection property="users" ofType="user">
<id column="id" property="id"></id>
<result column="username" property="username"></result>
<result column="address" property="address"></result>
<result column="sex" property="sex"></result>
<result column="birthday" property="birthday"></result>
</collection>
</resultMap>
<!--查询所有-->
<select id="findAll" resultMap="roleMap">
select u.*,r.id as rid,r.role_name,r.role_desc from role r
left outer join user_role ur on r.id = ur.rid
left outer join user u on u.id = ur.uid
</select>
</mapper>
UserTest.java
package com.yxj.test;
import com.yxj.dao.IUserDao;
import com.yxj.domain.User;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class UserTest {
private InputStream in;
private SqlSession sqlSession;
private IUserDao userDao;
@Before//用于在测试方法执行之前执行
public void inyxj()throws Exception{
//1.读取配置文件,生成字节输入流
in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.获取SqlSessionFactory
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
//3.获取SqlSession对象
sqlSession = factory.openSession(true);
//4.获取dao的代理对象
userDao = sqlSession.getMapper(IUserDao.class);
}
@After//用于在测试方法执行之后执行
public void destroy()throws Exception{
//提交事务
// sqlSession.commit();
//6.释放资源
sqlSession.close();
in.close();
}
/**
* 测试查询所有
*/
@Test
public void testFindAll(){
List<User> users = userDao.findAll();
for(User user : users){
System.out.println("-----每个用户的信息------");
System.out.println(user);
System.out.println(user.getRoles());
}
}
}
RoleTest.java
package com.yxj.test;
import com.yxj.dao.IRoleDao;
import com.yxj.domain.Role;
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.junyxj.After;
import org.junyxj.Before;
import org.junyxj.Test;
import java.io.InputStream;
import java.util.List;
/**
* @author 黑马程序员
* @Company http://www.yxjhiema.com
*/
public class RoleTest {
private InputStream in;
private SqlSession sqlSession;
private IRoleDao roleDao;
@Before//用于在测试方法执行之前执行
public void inyxj()throws Exception{
//1.读取配置文件,生成字节输入流
in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.获取SqlSessionFactory
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
//3.获取SqlSession对象
sqlSession = factory.openSession(true);
//4.获取dao的代理对象
roleDao = sqlSession.getMapper(IRoleDao.class);
}
@After//用于在测试方法执行之后执行
public void destroy()throws Exception{
//提交事务
// sqlSession.commit();
//6.释放资源
sqlSession.close();
in.close();
}
/**
* 测试查询所有
*/
@Test
public void testFindAll(){
List<Role> roles = roleDao.findAll();
for(Role role : roles){
System.out.println("---每个角色的信息----");
System.out.println(role);
System.out.println(role.getUsers());
}
}
}
16 关联关系总结
一对一,在任意一方引入对方主键作为外键;
一对多,在"多"的一方,添加"一"的一方的主键外键
多对多,产生中间关系表,引入两张表的主键作为外键,两个主键成为联合
主键.
17 常用配置
db.properties
jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/yxjmydatabase?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC
jdbc.username=root
jdbc.password=123456
log4j.properties
# Global logging configuration
log4j.rootLogger=ERROR,stdout
# MyBatis logging configuration.
log4j.logger.yxj.com.yxj=DEBUG
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
18 图片