0.概述
一.1对1的关系
背景描述:订单表和用户表是1对1的关系,1个订单只能隶属于1个用户。
1.1 新建工程
数据库脚本:
1.tb_orders表
CREATE TABLE `tb_orders` (
`id` int(11) NOT NULL,
`order_time` datetime NOT NULL,
`total` double(255,0) NOT NULL,
`uid` int(11) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
2.tb_users表
CREATE TABLE `tb_users` (
`id` int(11) NOT NULL,
`user_name` varchar(255) DEFAULT NULL,
`birthday` datetime DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
1.2 配置pom文件中的依赖
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.13</version>
<scope>test</scope>
</dependency>
<!--mywql dueong -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.32</version>
</dependency>
<!--mybaits -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<!-- log4j-->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<!-- 分页插件-->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>3.7.5</version>
</dependency>
<dependency>
<groupId>com.github.jsqlparser</groupId>
<artifactId>jsqlparser</artifactId>
<version>0.9.1</version>
</dependency>
1.3 实体层
1.orders实体
package com.ljf.mybaits.relation.mapping.domain;
import java.util.Date;
/**
* @ClassName: Orders
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/17 21:30:37
* @Version: V1.0
**/
public class Orders {
private int id;
private Date orderTime;
private double total;
//当前订单属于哪一个用户
private Users user;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public Date getOrderTime() {
return orderTime;
}
public void setOrderTime(Date orderTime) {
this.orderTime = orderTime;
}
public double getTotal() {
return total;
}
public void setTotal(double total) {
this.total = total;
}
public Users getUser() {
return user;
}
public void setUser(Users user) {
this.user = user;
}
@Override
public String toString() {
return "Orders{" +
"id=" + id +
", orderTime=" + orderTime +
", total=" + total +
", user=" + user +
'}';
}
}
2.users实体
package com.ljf.mybaits.relation.mapping.domain;
import java.util.Date;
/**
* @ClassName: Users
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/17 21:30:28
* @Version: V1.0
**/
public class Users {
private int id;
private String userName;
private Date birthday;
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 Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
@Override
public String toString() {
return "Users{" +
"id=" + id +
", userName='" + userName + '\'' +
", birthday=" + birthday +
'}';
}
}
1.4 dao层代码
package com.ljf.mybaits.relation.mapping.dao;
import com.ljf.mybaits.relation.mapping.domain.Orders;
import java.util.List;
public interface OrdersMapper {
//查询全部的方法
public List<Orders> findAll();
}
1.5 service层代码
1.service的接口
package com.ljf.mybaits.relation.mapping.service;
import com.ljf.mybaits.relation.mapping.domain.Orders;
import java.io.IOException;
import java.util.List;
public interface OrderService {
public List<Orders> findAll() throws IOException;
}
2.service的实现层
package com.ljf.mybaits.relation.mapping.service.impl;
import com.ljf.mybaits.relation.mapping.dao.OrdersMapper;
import com.ljf.mybaits.relation.mapping.domain.Orders;
import com.ljf.mybaits.relation.mapping.service.OrderService;
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.IOException;
import java.io.InputStream;
import java.util.List;
/**
* @ClassName: OrderServiceImpl
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/17 23:09:12
* @Version: V1.0
**/
public class OrderServiceImpl implements OrderService {
@Override
public List<Orders> findAll() throws IOException {
InputStream resourceAsStream = Resources.getResourceAsStream("mybaitsConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
OrdersMapper mapper = sqlSession.getMapper(OrdersMapper.class);
List<Orders> orderList = mapper.findAll();
sqlSession.close();
return orderList;
}
}
1.6 resouces下的配置文件
1.log4j的配置
######################
## set log levels
######################
log4j.rootLogger=DEBUG,info,CONSOLE,FILEOUT
#DEBUG,CONSOLE,FILE,ROLLING_FILE,MAIL,DATABASE
log4j.addivity.org.apache=true
######################
## CONSOLE Appender ##
######################
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.Threshold=DEBUG
log4j.appender.CONSOLE.Target=System.out
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=[%-5p][%d{yyyy-MM-dd HH\:mm\:ss,SSS}][%c] \:%m%n
#log4j.appender.CONSOLE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n\u00A0
#log4j.appender.CONSOLE.layout.ConversionPattern=[start]%d{DATE}[DATE]%n%p[PRIORITY]%n%x[NDC]%n%t[THREAD] n%c[CATEGORY]%n%m[MESSAGE]%n%n
######################
## Rolling File Appender
######################
log4j.appender.FILEOUT=org.apache.log4j.RollingFileAppender
log4j.appender.FILEOUT.File=E:/logs/allError.log
#log4j.appender.FILEOUT.Threshold=ALL
log4j.appender.FILEOUT.Threshold=INFO
log4j.appender.FILEOUT.Append=true
log4j.appender.fileout.MaxFileSize=1000KB
#log4j.appender.ROLLING_FILE.MaxBackupIndex=1
log4j.appender.FILEOUT.layout=org.apache.log4j.PatternLayout
log4j.appender.FILEOUT.layout.ConversionPattern=[%-5p][%d{yyyy-MM-dd HH\:mm\:ss,SSS}][%c] \:%m%n
#log4j.appender.CONSOLE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n\u00A0
#######################
#info log
log4j.logger.info=info
log4j.appender.info=org.apache.log4j.DailyRollingFileAppender
log4j.appender.info.DatePattern='_'yyyy-MM-dd'.log'
log4j.appender.info.File=d:/info.log
log4j.appender.info.Append=true
log4j.appender.info.Threshold=INFO
log4j.appender.info.layout=org.apache.log4j.PatternLayout
log4j.appender.info.layout.ConversionPattern=[%-5p][%d{yyyy-MM-dd HH\:mm\:ss,SSS}][%c] \:%m%n
### File Appender
#######################
#log4j.appender.FILE=org.apache.log4j.FileAppender
#log4j.appender.FILE.File=E:/logs/all.log
#log4j.appender.FILE.Append=true
#log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
#log4j.appender.CONSOLE.layout.ConversionPattern=[%-5p][%d{yyyy-MM-dd HH\:mm\:ss,SSS}][%c] \:%m%n
##log4j.appender.CONSOLE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n\u00A0
#####################
## Socket Appender
#####################
#log4j.appender.SOCKET=org.apache.log4j.RollingFileAppender
#log4j.appender.SOCKET.RemoteHost=localhost
#log4j.appender.SOCKET.Port=5001
#log4j.appender.SOCKET.LocationInfo=true
## Set up for Log Facter 5
#log4j.appender.SOCKET.layout=org.apache.log4j.PatternLayout
#log4j.appender.SOCET.layout.ConversionPattern=[start]%d{DATE}[DATE]%n%p[PRIORITY]%n%x[NDC]%n%t[THREAD]%n%c[CATEGORY]%n%m[MESSAGE]%n%n
#########################
## Log Factor 5 Appender
#########################
#log4j.appender.LF5_APPENDER=org.apache.log4j.lf5.LF5Appender
#log4j.appender.LF5_APPENDER.MaxNumberOfRecords=2000
########################
## SMTP Appender
########################
#log4j.appender.MAIL=org.apache.log4j.net.SMTPAppender
#log4j.appender.MAIL.Threshold=FATAL
#log4j.appender.MAIL.BufferSize=10
#[email protected]
#log4j.appender.MAIL.SMTPHost=mail.openwolf.com
#log4j.appender.MAIL.Subject=Log4J Message
#[email protected]
#log4j.appender.MAIL.layout=org.apache.log4j.PatternLayout
#log4j.appender.MAIL.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n
#########################
## JDBC Appender
########################
#log4j.appender.DATABASE=org.apache.log4j.jdbc.JDBCAppender
#log4j.appender.DATABASE.URL=jdbc:mysql://localhost:3306/test
#log4j.appender.DATABASE.driver=com.mysql.jdbc.Driver
#log4j.appender.DATABASE.user=root
#log4j.appender.DATABASE.password=root
#log4j.appender.DATABASE.sql=INSERT INTO LOG4J (Message) VALUES ('[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n')
#log4j.appender.DATABASE.layout=org.apache.log4j.PatternLayout
#log4j.appender.DATABASE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n
#log4j.appender.A1=org.apache.log4j.DailyRollingFileAppender
#log4j.appender.A1.File=SampleMessages.log4j
#log4j.appender.A1.DatePattern=yyyyMMdd-HH'.log4j'
#log4j.appender.A1.layout=org.apache.log4j.xml.XMLLayout
####################
### myself Appender
####################
#log4j.appender.im = net.cybercorlin.util.logger.appender.IMAppender
#log4j.appender.im.host = mail.cybercorlin.net
#log4j.appender.im.username = username
#log4j.appender.im.password = password
#log4j.appender.im.recipient = [email protected]
#log4j.appender.im.layout=org.apache.log4j.PatternLayout
#log4j.appender.im.layout.ConversionPattern =[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n
2.jdbc.properties文件
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/nongda
jdbc.username=root
jdbc.password=
3.mybaitsConfig.xml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>
<properties resource="mybaits-jdbc.properties"></properties>
<!-- 起别名-->
<typeAliases>
<typeAlias type="com.ljf.mybaits.relation.mapping.domain.Users" alias="user"></typeAlias>
<typeAlias type="com.ljf.mybaits.relation.mapping.domain.Orders" alias="order"></typeAlias>
</typeAliases>
<!-- 注册类型注册器
<typeHandlers>
<typeHandler handler="com.mybaits.demo.handler.DataTypeTransfer"></typeHandler>
</typeHandlers>
-->
<!--配置分页插件 -->
<plugins>
<plugin interceptor="com.github.pagehelper.PageHelper">
<property name="dialect" value="mysql"/>
</plugin>
</plugins>
<!-- 数据源环境 -->
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"></transactionManager>
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</dataSource>
</environment>
</environments>
<!-- xxxmapper.xml都要在mybaits.config.xml文件中注册-->
<mappers>
<mapper resource="com/mybaits/mapper/OrderMapper.xml"></mapper>
</mappers>
</configuration>
4.mapper.xml配置文件
1.orders.mapper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="com.ljf.mybaits.relation.mapping.dao.OrdersMapper">
<resultMap id="orderMap" type="order">
<!--手动指定字段与实体属性的映射关系
column: 数据表的字段名称
property:实体的属性名称
-->
<!-- -->
<id column="oid" property="id"></id>
<result column="order_time" property="orderTime"></result>
<result column="total" property="total"></result>
<!-- 方式一: user为Users实体中User类型的属性名 -->
<result column="id" property="user.id"></result>
<result column="user_name" property="user.userName"></result>
<result column="password" property="user.password"></result>
<result column="birthday" property="user.birthday"></result>
<!-- 方法二:
property: 当前实体(order)中的属性名称(private User user)
javaType: 当前实体(order)中的属性的类型(User)
<association property="user" javaType="user">
<id column="id" property="id"></id>
<result column="user_name" property="userName"></result>
<result column="password" property="password"></result>
<result column="birthday" property="birthday"></result>
</association>
-->
</resultMap>
<select id="findAll" resultMap="orderMap">
SELECT o.id oid,o.order_time,o.total,u.id,u.user_name,u.birthday FROM tb_orders o,tb_users u WHERE o.uid=u.id
</select>
</mapper>
1.7 执行结果:
package com.ljf.mybaits.relation.mapping;
import com.ljf.mybaits.relation.mapping.domain.Orders;
import com.ljf.mybaits.relation.mapping.service.OrderService;
import com.ljf.mybaits.relation.mapping.service.impl.OrderServiceImpl;
import java.io.IOException;
import java.util.List;
/**
* Hello world!t
*
*/
public class App
{
public static void main( String[] args ) throws IOException {
OrderService os=new OrderServiceImpl();
List<Orders> orderList=os.findAll();
for (Orders order : orderList) {
System.out.println(order);
}
System.out.println( "Hello World!" );
}
}
二.1对n的关系
背景描述:用户表和订单表是1对n的关系,1个用户可以拥有多个订单。
2.1 userMapper配置文件
<?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="yonghuMapper"> -->
<mapper namespace="com.ljf.mybaits.relation.mapping.dao.UserMapper">
<!-- 查询, 在mybaitsconfig.xml文件中给起了别名 -->
<resultMap id="userMap" type="user">
<id column="id" property="id"></id>
<result column="user_name" property="userName"></result>
<result column="password" property="password"></result>
<result column="birthday" property="birthday"></result>
<!--配置集合信息
property:集合名称
ofType:当前集合中的数据类型
-->
<collection property="orderList" ofType="order">
<!--封装order的数据-->
<id column="oid" property="id"></id>
<result column="order_time" property="orderTime"></result>
<result column="total" property="total"></result>
</collection>
</resultMap>
<select id="findAll" resultMap="userMap">
SELECT o.id oid,o.order_time,o.total,u.id,u.user_name,u.birthday FROM tb_orders o,tb_users u WHERE o.uid=u.id
</select>
</mapper>
2.2 mybaitsconfig.xml配置文件
在此配置文件中添加此实体类的别名
2.3 dao层
package com.ljf.mybaits.relation.mapping.dao;
import com.ljf.mybaits.relation.mapping.domain.Users;
import java.io.IOException;
import java.util.List;
public interface UserMapper {
List<Users> findAll() throws IOException;
}
2.4 service层
1.userservice代码
package com.ljf.mybaits.relation.mapping.service;
import com.ljf.mybaits.relation.mapping.domain.Orders;
import com.ljf.mybaits.relation.mapping.domain.Users;
import java.io.IOException;
import java.util.List;
public interface UserService {
public List<Users> findAll() throws IOException;
}
2.userservice的实现层代码
package com.ljf.mybaits.relation.mapping.service.impl;
import com.ljf.mybaits.relation.mapping.dao.UserMapper;
import com.ljf.mybaits.relation.mapping.domain.Users;
import com.ljf.mybaits.relation.mapping.service.UserService;
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.IOException;
import java.io.InputStream;
import java.util.List;
/**
* @ClassName: UserServiceImpl
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/18 13:29:09
* @Version: V1.0
**/
public class UserServiceImpl implements UserService {
@Override
public List<Users> findAll() throws IOException {
InputStream resourceAsStream = Resources.getResourceAsStream("mybaitsConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
List<Users> userList = mapper.findAll();
sqlSession.close();
return userList;
}
}
2.5 实体层
package com.ljf.mybaits.relation.mapping.domain;
import java.util.Date;
import java.util.List;
/**
* @ClassName: Users
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/17 21:30:28
* @Version: V1.0
**/
public class Users {
private int id;
private String userName;
private Date birthday;
//描述的是当前用户存在哪些订单
private List<Orders> orderList;
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 Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public List<Orders> getOrderList() {
return orderList;
}
public void setOrderList(List<Orders> orderList) {
this.orderList = orderList;
}
@Override
public String toString() {
return "Users{" +
"id=" + id +
", userName='" + userName + '\'' +
", birthday=" + birthday +
", orderList=" + orderList +
'}';
}
}
2.6 调用
package com.ljf.mybaits.relation.mapping;
import com.ljf.mybaits.relation.mapping.domain.Users;
import com.ljf.mybaits.relation.mapping.service.UserService;
import com.ljf.mybaits.relation.mapping.service.impl.UserServiceImpl;
import java.io.IOException;
import java.util.List;
/**
* @ClassName: APP2
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/18 13:18:28
* @Version: V1.0
**/
public class APP2 {
public static void main(String[] args) throws IOException {
UserService us=new UserServiceImpl();
List<Users> userList= us.findAll();
for (Users user : userList) {
System.out.println(user);
}
}
}
三.n对n的关系
背景描述:多对多的关系为:一个用户对应多个角色,用户和角色需要一张关系表来维护
3.1 数据库表设计
CREATE TABLE `tb_users` (
`id` int(11) NOT NULL,
`user_name` varchar(255) DEFAULT NULL,
`birthday` datetime DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `tb_user_role` (
`uid` int(11) NOT NULL,
`rid` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `tb_role` (
`id` int(11) NOT NULL,
`role_name` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
3.2 实体bean的设计
package com.ljf.mybaits.relation.mapping.domain;
/**
* @ClassName: Role
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/18 14:42:38
* @Version: V1.0
**/
public class Role {
private int id;
private String roleName;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getRoleName() {
return roleName;
}
public void setRoleName(String roleName) {
this.roleName = roleName;
}
@Override
public String toString() {
return "Role{" +
"id=" + id +
", roleName='" + roleName + '\'' +
'}';
}
}
user:
package com.ljf.mybaits.relation.mapping.domain;
import java.util.Date;
import java.util.List;
/**
* @ClassName: Users
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/17 21:30:28
* @Version: V1.0
**/
public class Users {
private int id;
private String userName;
private Date birthday;
//描述的是当前用户存在哪些订单
private List<Orders> orderList;
//描述的是当前用户具备哪些角色
private List<Role> roleList;
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 Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public List<Orders> getOrderList() {
return orderList;
}
public void setOrderList(List<Orders> orderList) {
this.orderList = orderList;
}
public List<Role> getRoleList() {
return roleList;
}
public void setRoleList(List<Role> roleList) {
this.roleList = roleList;
}
@Override
public String toString() {
return "Users{" +
"id=" + id +
", userName='" + userName + '\'' +
", birthday=" + birthday +
", orderList=" + orderList +
", roleList=" + roleList +
'}';
}
}
3.3 userMapper配置文件
<resultMap id="userRoleMap" type="user">
<!--user的信息-->
<id column="userId" property="id"></id>
<result column="user_name" property="userName"></result>
<result column="birthday" property="birthday"></result>
<!--user内部的roleList信息 role是在mybaitsconfig.xml文件中给起了别名 -->
<collection property="roleList" ofType="role">
<id column="rid" property="id"></id>
<result column="role_name" property="roleName"></result>
</collection>
</resultMap>
<select id="findUserAndRoleAll" resultMap="userRoleMap">
select a.id uid,a.user_name,a.birthday,b.uid,b.rid,c.id cid ,c.role_name from tb_users as a ,tb_user_role as b ,tb_role as c
where a.id=b.uid and b.rid=c.id
</select>
3.4 dao层
package com.ljf.mybaits.relation.mapping.dao;
import com.ljf.mybaits.relation.mapping.domain.Users;
import java.io.IOException;
import java.util.List;
public interface UserMapper {
List<Users> findAll() throws IOException;
public List<Users> findUserAndRoleAll();
}
3.5 service层
service接口
package com.ljf.mybaits.relation.mapping.service;
import com.ljf.mybaits.relation.mapping.domain.Orders;
import com.ljf.mybaits.relation.mapping.domain.Users;
import java.io.IOException;
import java.util.List;
public interface UserService {
public List<Users> findAll() throws IOException;
public List<Users> findUserAndRoleAll() throws IOException;
}
service的实现层
package com.ljf.mybaits.relation.mapping.service.impl;
import com.ljf.mybaits.relation.mapping.dao.UserMapper;
import com.ljf.mybaits.relation.mapping.domain.Users;
import com.ljf.mybaits.relation.mapping.service.UserService;
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.IOException;
import java.io.InputStream;
import java.util.List;
/**
* @ClassName: UserServiceImpl
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/18 13:29:09
* @Version: V1.0
**/
public class UserServiceImpl implements UserService {
@Override
public List<Users> findAll() throws IOException {
InputStream resourceAsStream = Resources.getResourceAsStream("mybaitsConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
List<Users> userList = mapper.findAll();
sqlSession.close();
return userList;
}
@Override
public List<Users> findUserAndRoleAll() throws IOException {
InputStream resourceAsStream = Resources.getResourceAsStream("mybaitsConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
List<Users> userAndRoleAll = mapper.findUserAndRoleAll();
sqlSession.close();
return userAndRoleAll;
}
}
3.6 调用
package com.ljf.mybaits.relation.mapping;
import com.ljf.mybaits.relation.mapping.domain.Users;
import com.ljf.mybaits.relation.mapping.service.UserService;
import com.ljf.mybaits.relation.mapping.service.impl.UserServiceImpl;
import java.io.IOException;
import java.util.List;
/**
* @ClassName: App3
* @Description: TODO
* @Author: liujianfu
* @Date: 2021/02/18 14:50:15
* @Version: V1.0
**/
public class App3 {
public static void main(String[] args) throws IOException {
UserService us=new UserServiceImpl();
List<Users> userAndRoleAll =us.findUserAndRoleAll();
for (Users user : userAndRoleAll) {
System.out.println(user);
}
}
}