Mybatis相关配置属性

￡神魔★判官ぃ 2023-10-02 19:57 31阅读 0赞

![2beb5ff7e9e7405583940f8007ed1d41.png][]

## RoleMapper ##

package com.itheima.sh.dao;
    
    
    import com.itheima.sh.pojo.Role;
    import org.apache.ibatis.annotations.Param;
    
    import java.util.List;
    
    public interface RoleMapper {
        //分页查询角色以及对应的用户和权限信息
        List<Role> queryAllRolesAndUsersAndPermi(@Param("startIndex") int startIndex, @Param("pageSize") int pageSize);
    
    }

## UserMapper ##

package com.itheima.sh.dao;
    
    
    import com.itheima.sh.pojo.User;
    import org.apache.ibatis.annotations.Param;
    import org.apache.ibatis.annotations.Update;
    
    import java.util.List;
    
    public interface UserMapper {
        //分页查询用户
        List<User> queryAllUsersAndRoles(@Param("startIndex") int startIndex, @Param("pageSize")int pageSize);
        //根据用户id修改用户名称 密码
        @Update("update t_user set username=#{username},password=#{password} where id=#{id}")
        void updateUserById(User user);
    }

## UserRoleMapper ##

package com.itheima.sh.dao;
    
    import org.apache.ibatis.annotations.Delete;
    import org.apache.ibatis.annotations.Insert;
    import org.apache.ibatis.annotations.Param;
    
    public interface UserRoleMapper {
        //根据用户id删除中间表数据
        @Delete("delete from t_user_role where user_id=#{id}")
        void deleteUserAndRoleByUID(@Param("id") String id);
        //向中间表插入新的数据
        @Insert("insert into t_user_role values(#{uid},#{roleId})")
        void addUserAndRoleID(@Param("uid")String id, @Param("roleId")String roleId);
    }

## Permission ##

package com.itheima.sh.pojo;
    
    import java.io.Serializable;
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * 权限
     */
    public class Permission implements Serializable{
        private String id;
        private String name; // 权限名称
        private String keyword; // 权限关键字，用于权限控制
        private String description; // 描述
        //一个权限可以保存多个角色
        private List<Role> roles = new ArrayList<Role>(0);
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getKeyword() {
            return keyword;
        }
    
        public void setKeyword(String keyword) {
            this.keyword = keyword;
        }
    
        public String getDescription() {
            return description;
        }
    
        public void setDescription(String description) {
            this.description = description;
        }
    
        public List<Role> getRoles() {
            return roles;
        }
    
        public void setRoles(List<Role> roles) {
            this.roles = roles;
        }
    
        @Override
        public String toString() {
            return "Permission{" +
                    "id='" + id + '\'' +
                    ", name='" + name + '\'' +
                    ", keyword='" + keyword + '\'' +
                    ", description='" + description + '\'' +
                    ", roles=" + roles +
                    '}';
        }
    }

## Role ##

package com.itheima.sh.pojo;
    
    import java.util.ArrayList;
    import java.util.List;
    
    /*
        角色
     */
    public class Role {
    
        private String id;
        private String name;
        private String keyword;
        private String description;
        //一个角色可以保存多个用户
        private List<User> users = new ArrayList<User>(0);
        //一个角色可以保存多个权限
        private List<Permission> permissions = new ArrayList<Permission>(0);
    
        @Override
        public String toString() {
            return "Role{" +
                    "id=" + id +
                    ", name='" + name + '\'' +
                    ", keyword='" + keyword + '\'' +
                    ", description='" + description + '\'' +
                    ", users=" + users +
                    ", permissions=" + permissions +
                    '}';
        }
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getKeyword() {
            return keyword;
        }
    
        public void setKeyword(String keyword) {
            this.keyword = keyword;
        }
    
        public String getDescription() {
            return description;
        }
    
        public void setDescription(String description) {
            this.description = description;
        }
    
        public List<User> getUsers() {
            return users;
        }
    
        public void setUsers(List<User> users) {
            this.users = users;
        }
    
        public List<Permission> getPermissions() {
            return permissions;
        }
    
        public void setPermissions(List<Permission> permissions) {
            this.permissions = permissions;
        }
    }

## User ##

package com.itheima.sh.pojo;
    
    import java.util.ArrayList;
    import java.util.List;
    /*
        用户
     */
    public class User {
        private String id;
        private String username;
        private String password;
        private String email;
        private String createTime;
        private String updateTime;
        private String remark;
        private List<String> roleIds;
        //一个用户可以保存多个角色
        private List<Role> roles = new ArrayList<Role>(0);
    
        public List<String> getRoleIds() {
            return roleIds;
        }
    
        public void setRoleIds(List<String> roleIds) {
            this.roleIds = roleIds;
        }
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username = username;
        }
    
        public String getPassword() {
            return password;
        }
    
        public void setPassword(String password) {
            this.password = password;
        }
    
        public String getEmail() {
            return email;
        }
    
        public void setEmail(String email) {
            this.email = email;
        }
    
        public String getCreateTime() {
            return createTime;
        }
    
        public void setCreateTime(String createTime) {
            this.createTime = createTime;
        }
    
        public String getUpdateTime() {
            return updateTime;
        }
    
        public void setUpdateTime(String updateTime) {
            this.updateTime = updateTime;
        }
    
        public String getRemark() {
            return remark;
        }
    
        public void setRemark(String remark) {
            this.remark = remark;
        }
    
        public List<Role> getRoles() {
            return roles;
        }
    
        public void setRoles(List<Role> roles) {
            this.roles = roles;
        }
    
        @Override
        public String toString() {
            return "User{" +
                    "id=" + id +
                    ", username='" + username + '\'' +
                    ", password='" + password + '\'' +
                    ", email='" + email + '\'' +
                    ", createTime='" + createTime + '\'' +
                    ", updateTime='" + updateTime + '\'' +
                    ", remark='" + remark + '\'' +
                    ", roleIds=" + roleIds +
                    ", roles=" + roles +
                    '}';
        }
    }

## RoleServiceImpl ##

package com.itheima.sh.service;
    
    import com.itheima.sh.dao.RoleMapper;
    import com.itheima.sh.pojo.Role;
    import com.itheima.sh.util.SqlSessionUtil;
    import org.apache.ibatis.session.SqlSession;
    
    import java.util.List;
    
    public class RoleServiceImpl {
        public List<Role> queryAllRolesAndUsersAndPermi(int startIndex, int pageSize) {
            //1.获取会话工厂对象
            SqlSession sqlSession = SqlSessionUtil.getSqlSession(false);
            //2.获取接口代理对象
            RoleMapper mapper = sqlSession.getMapper(RoleMapper.class);
            //3.使用接口代理对象调用接口中的方法
            List<Role> roleList = mapper.queryAllRolesAndUsersAndPermi(startIndex,pageSize);
            //4.释放资源
            sqlSession.close();
            //5.返回集合给web层
            return roleList;
        }
    }

## UserServiceImpl ##

package com.itheima.sh.service;
    
    import com.itheima.sh.dao.UserMapper;
    import com.itheima.sh.dao.UserRoleMapper;
    import com.itheima.sh.pojo.User;
    import com.itheima.sh.util.SqlSessionUtil;
    import org.apache.ibatis.session.SqlSession;
    
    import java.util.List;
    
    public class UserServiceImpl {
        public List<User> queryAllUsersAndRoles(int startIndex, int pageSize) {
            //1.获取会话工厂对象
            SqlSession sqlSession = SqlSessionUtil.getSqlSession(false);
            //2.获取接口代理对象
            UserMapper mapper = sqlSession.getMapper(UserMapper.class);
            //3.使用接口代理对象调用接口中的分页查询用户和角色的方法
            List<User> userList = mapper.queryAllUsersAndRoles(startIndex,pageSize);
            //4.释放资源
            sqlSession.close();
            //5.返回集合给web层的调用者
            return userList;
    
        }
        //修改用户方法
        public void updateUserById(User user) {
            //1.获取会话工厂对象
            SqlSession sqlSession = SqlSessionUtil.getSqlSession(true);
            //2.获取接口代理对象
            UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
            UserRoleMapper userRoleMapper = sqlSession.getMapper(UserRoleMapper.class);
    
            //3.使用UserMapper接口代理对象调用UserMapper接口中根据id更新用户的方法
            userMapper.updateUserById(user);
    
            //4.使用UserRoleMapper接口代理对象调用UserRoleMapper的方法根据用户id删除中间表t_user_role中有关当前用户id所有的信息
            userRoleMapper.deleteUserAndRoleByUID(user.getId());
    
            //5.使用UserRoleMapper接口代理对象调用UserRoleMapper的方法将当前用户id和新的角色id插入到中间表t_user_role中
            //注意在User实体类中使用集合private List<String> roleIds;保存多个角色id，因为一个用户可以有多个角色
            //这里需要遍历集合roleIds取出每个角色id
            List<String> roleIds = user.getRoleIds();
            //遍历
            /*
                admin(1)   原来角色 管理员(1) 会员(2)
                admin(1)   新的角色 会员(2)  游客(3)
             */
            for (String roleId : roleIds) {
                //6.将当前用户的用户id和角色id插入到中间表t_user_role
                userRoleMapper.addUserAndRoleID(user.getId(),roleId);
            }
        }
    }

## SqlSessionUtil ##

package com.itheima.sh.util;
    
    import org.apache.ibatis.io.Resources;
    import org.apache.ibatis.session.SqlSession;
    import org.apache.ibatis.session.SqlSessionFactory;
    import org.apache.ibatis.session.SqlSessionFactoryBuilder;
    
    /*
        工具类特点：
            1.位于util包
            2.私有化构造方法
            3.提供静态方法
     */
    public class SqlSessionUtil {
        private static SqlSessionFactory factory = null;
    
        // 2.私有化构造方法
        private SqlSessionUtil() {
        }
    
        //静态代码块：类加载就执行获取工厂对象
        static {
            try {
                //1.获取工厂创造类对象
                SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
                //2.获取会话工厂对象
                factory = builder.build(Resources.getResourceAsStream("mybatis-config.xml"));
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        // 3.提供静态方法
        //提供会话对象，设置自动提交事务
        public static SqlSession getSqlSession() {
    
            SqlSession sqlSession = factory.openSession(true);
            //返回会话对象
            return sqlSession;
        }
    
        //提供会话对象，设置自动提交事务
        public static SqlSession getSqlSession(boolean isAutoCommit) {
            SqlSession sqlSession = factory.openSession(isAutoCommit);
            //返回会话对象
            return sqlSession;
        }
    
        //编写静态方法接收会话对象，手动提交事务并且关闭会话对象
        public static void commitAndClose(SqlSession sqlSession) {
            //防止空指针，判断
            if (sqlSession != null) {
                //一切正常提交事务
                sqlSession.commit();
                //关闭会话对象
                sqlSession.close();
            }
        }
    
        public static void commit(SqlSession sqlSession) {
            //防止空指针，判断
            if (sqlSession != null) {
                //一切正常提交事务
                sqlSession.commit();
    
            }
        }
    
        public static void close(SqlSession sqlSession) {
            //防止空指针，判断
            if (sqlSession != null) {
               sqlSession.close();
    
            }
        }
    
        //编写静态方法接收会话对象，回滚事务并且关闭会话对象
        public static void rollbackAndClose(SqlSession sqlSession) {
            //防止空指针，判断
            if (sqlSession != null) {
                //出现正常回顾事务
                sqlSession.rollback();
                //关闭会话对象
                sqlSession.close();
            }
        }
    
    }

## QueryAllRolesAndUsersAndPermi ##

package com.itheima.sh.web;
    
    import com.itheima.sh.pojo.Role;
    import com.itheima.sh.service.RoleServiceImpl;
    
    import java.util.List;
    import java.util.Scanner;
    
    /*
        分页查询角色和对应的用户以及权限信息
        入口：
     */
    public class QueryAllRolesAndUsersAndPermi {
        public static void main(String[] args) {
            //1.创建键盘录入的对象
            Scanner sc = new Scanner(System.in);
            //2.提示
            System.out.println("请输入起始索引:");
            //获取
            int startIndex = sc.nextInt();//起始索引
    
            System.out.println("请输入每页条数:");
            //获取
            int pageSize = sc.nextInt();//每页条数
    
            //3.创建业务层对象
            RoleServiceImpl roleService = new RoleServiceImpl();
            //4.使用业务层对象调用查询角色和对应的用户以及权限信息
            /*
                roleList = [Role{id=1, name='管理员', keyword='ROLE_ADMIN', description='这是管理员',
                                users=[User{id=1, username='admin', password='123', email='admin@163.com',
                                                            createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0',
                                                                        remark='null', roleIds=null, roles=[]},
                                      User{id=4, username='wangwu', password='123', email='wangwu@163.com',
                                                                        createTime='2021-12-05 14:50:35.0',
                                                                        updateTime='2021-12-05 14:50:35.0',
                                                                         remark='null', roleIds=null, roles=[]},
                                     User{id=6, username='tianqi', password='123', email='tianqi@163.com',
                                                                          createTime='2021-12-05 14:50:35.0',
                                                                          updateTime='2021-12-05 14:50:35.0', remark='null',
                                                                          roleIds=null, roles=[]},
                                    User{id=8, username='杨幂', password='123', email='yangmi@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]},
                                    User{id=9, username='李沁', password='123', email='liqin@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]},
                                    User{id=10, username='赵丽颖', password='123', email='zhaoliying@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}],
                               permissions=[com.itheima.sh.pojo.Permission@691a7f8f, com.itheima.sh.pojo.Permission@50a7bc6e, com.itheima.sh.pojo.Permission@161b062a, com.itheima.sh.pojo.Permission@17c1bced]}, Role{id=2, name='会员', keyword='ROLE_MEMBER', description='这是会员', users=[User{id=1, username='admin', password='123', email='admin@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}, User{id=2, username='zhansan', password='123', email='zhansan@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}, User{id=3, username='lisi', password='123', email='lisi@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}, User{id=5, username='zhaoliu', password='123', email='zhaoliu@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}, User{id=8, username='杨幂', password='123', email='yangmi@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}, User{id=10, username='赵丽颖', password='123', email='zhaoliying@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[]}], permissions=[com.itheima.sh.pojo.Permission@2d9d4f9d, com.itheima.sh.pojo.Permission@4034c28c]}]
             */
            List<Role> roleList=roleService.queryAllRolesAndUsersAndPermi(startIndex,pageSize);
            System.out.println(roleList.size());//2
            //5.输出
            System.out.println("roleList = " + roleList);
        }
    }

## QueryAllUsersAndRoles ##

package com.itheima.sh.web;
    
    import com.itheima.sh.pojo.User;
    import com.itheima.sh.service.UserServiceImpl;
    
    import java.util.List;
    import java.util.Scanner;
    
    /*
        需求：分页查询用户和对应的角色信息，然后将信息输出到idea控制台。
        入口
     */
    public class QueryAllUsersAndRoles {
        public static void main(String[] args) {
            //1.创建键盘录入的对象
            Scanner sc = new Scanner(System.in);
            //2.提示
            System.out.println("请输入起始索引:");
            //获取
            int startIndex = sc.nextInt();//起始索引
    
            System.out.println("请输入每页条数:");
            //获取
            int pageSize = sc.nextInt();//每页条数
            //3.创建业务层对象
            UserServiceImpl userService = new UserServiceImpl();
            //4.使用业务层对象调用业务层分页查询用户和角色的方法
            //将键盘录入的起始索引和每页条数传递到业务层
            //分页查询的是多个用户存储到list集合中
            List<User> userList = userService.queryAllUsersAndRoles(startIndex, pageSize);
            //5.判断集合是否有数据
            if (userList != null && userList.size() != 0) {
                //集合有数据
                /*
                    User{id=1, username='admin', password='123', email='admin@163.com', createTime='2021-12-05 14:50:35.0',
                        updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null,
                        roles=[Role{id=1, name='管理员', keyword='ROLE_ADMIN', description='这是管理员',
                        users=[], permissions=[]}, Role{id=2, name='会员', keyword='ROLE_MEMBER',
                        description='这是会员', users=[], permissions=[]}]}
                    User{id=2, username='zhansan', password='123', email='zhansan@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[Role{id=2, name='会员', keyword='ROLE_MEMBER', description='这是会员', users=[], permissions=[]}]}
                    User{id=3, username='lisi', password='123', email='lisi@163.com', createTime='2021-12-05 14:50:35.0', updateTime='2021-12-05 14:50:35.0', remark='null', roleIds=null, roles=[Role{id=2, name='会员', keyword='ROLE_MEMBER', description='这是会员', users=[], permissions=[]}]}
    
    
                 */
                userList.forEach(System.out::println);
            }else{
                //没查询到数据
                System.out.println("没有用户");
            }
        }
    }

## UpdateUserWeb ##

package com.itheima.sh.web;
    
    import com.itheima.sh.pojo.User;
    import com.itheima.sh.service.UserServiceImpl;
    
    import java.util.ArrayList;
    
    public class UpdateUserWeb {
        public static void main(String[] args) {
            /*
                需求：修改id是1的用户的密码为456，用户名为刘德华，扮演角色变为游客(提示：游客角色id是3)和会员(提示：会员角色id是2)
             */
            //1.创建实体类对象
            User user = new User();
            //2.向user对象中添加数据
            user.setId("1");//修改用户的id
            user.setUsername("刘德华");//用户的新用户名
            user.setPassword("456");//用户的新密码
            //创建集合保存当前用户新角色的id
            ArrayList<String> list = new ArrayList<>();
            list.add("2");//会员角色id是2
            list.add("3");//游客角色id是3
            user.setRoleIds(list);
            //3.创建业务层对象
            UserServiceImpl userService = new UserServiceImpl();
            //4.调用修改方法
            userService.updateUserById(user);
        }
    }

## RoleMapper.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.itheima.sh.dao.RoleMapper">
        <resultMap id="queryAllRolesAndUsersAndPermiResultMap" type="Role" autoMapping="true">
            
            <id column="rid" property="id"/>
            <result column="rname" property="name"/>
            <result column="rkwd" property="keyword"/>
            <result column="rdes" property="description"/>
            
            <collection property="users" ofType="User" autoMapping="true">
                
                <id column="id" property="id"/>
            </collection>
    
            
            <collection property="permissions" ofType="Permission" autoMapping="true">
                
                <id column="pid" property="id"/>
                <result column="pname" property="name"/>
                <result column="pkwd" property="keyword"/>
                <result column="pdes" property="description"/>
            </collection>
        </resultMap>
        
        <select id="queryAllRolesAndUsersAndPermi" resultMap="queryAllRolesAndUsersAndPermiResultMap">
            select temp.id rid,temp.name rname,temp.keyword rkwd,temp.description rdes,
                   u.*,p.id pid,p.name pname,p.keyword pkwd,p.description pdes
            from (select * from t_role limit #{startIndex},#{pageSize}) temp
            inner join t_user_role ur
            inner join t_user u
            inner join t_role_permission rp
            inner join t_permission p
            on temp.id=ur.role_id and ur.user_id=u.id and temp.id=rp.role_id and rp.permission_id = p.id
        </select>
    </mapper>

## UserMapper.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.itheima.sh.dao.UserMapper">
        
        <resultMap id="queryAllUsersAndRolesResultMap" type="User" autoMapping="true">
            
            <id column="id" property="id"/>
            
            <collection property="roles" ofType="Role" autoMapping="true">
                
                <id column="rid" property="id"/>
            </collection>
        </resultMap>
        
       <select id="queryAllUsersAndRoles" resultMap="queryAllUsersAndRolesResultMap">
           select temp.*,r.id rid,r.name,r.keyword,r.description
           from (select * from t_user limit #{startIndex},#{pageSize})  temp
           inner join t_user_role ur
           inner join t_role r
           on temp.id = ur.user_id and ur.role_id = r.id;
       </select>
    </mapper>

## db.properties ##

jdbc.driver=com.mysql.jdbc.Driver
    jdbc.url=jdbc:mysql://localhost:3306/day0801
    jdbc.username=root
    jdbc.password=1234

## logback.xml ##

<?xml version="1.0" encoding="UTF-8"?>
    <configuration>
        
        <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
            
            <target>System.out</target>
            <encoder>
                
                <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%-5level]  %c [%thread] : %msg%n</pattern>
            </encoder>
        </appender>
    
        
        <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
            <encoder>
                <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
                <charset>utf-8</charset>
            </encoder>
            
            <file>C:/code/itheima-data.log</file>
            
            <rollingPolicy
                    class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
                
                <fileNamePattern>C:/code/itheima-data2-%d{yyyy-MMdd}.log%i.gz</fileNamePattern>
                
                <maxFileSize>1MB</maxFileSize>
            </rollingPolicy>
        </appender>
    
        
        <root level="ALL">
            <appender-ref ref="CONSOLE"/>
            <appender-ref ref="FILE" />
        </root>
    </configuration>

## mybatis-config.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>
        
        <settings>
            
            <setting name="mapUnderscoreToCamelCase" value="true"/>
        </settings>
        
        <typeAliases>
            <package name="com.itheima.sh.pojo"></package>
        </typeAliases>
        
        <environments default="development">
            
            <environment id="development">
                
                
                <transactionManager type="JDBC"/>
                
                
                <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>
        
        <mappers>
            
            
            
            
            
            <package name="com.itheima.sh.dao"></package>
        </mappers>
    </configuration>

## 总结 ##

今日总结：  
1.映射文件方式实现动态sql:\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
1.<if test="判断条件">  
文本  
</if>  
如果判断条件为真，那么执行if标签的文本，如果为假就不执行

2. 多分支或者多选一  
<choose>  
<when test="判断条件">  
文本1  
</when>  
<when test="判断条件">  
文本2  
</when>  
<otherwise>  
文本3  
</otherwise>  
</choose>  
如果某个when的条件满足，则执行对应文本，不会执行下面的内容，如果不满足条件则继续执行下面的内容  
如果when中的所有判断条件都为false,那么执行otherwise文本

3.<where>标签作用：1）加where关键字 2）去掉多余的and和or

4.<set>标签作用：1）加set关键字 2）去掉多余的逗号

5.用来遍历数组或者集合  
<foreach collection="数组或者集合名" item="元素" separator="元素分隔符" open="以什么开始" close="以什么结尾">  
\#\{元素\}  
</foreach>

2.多表查询：\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
1）一对一查询：  
<resultMap id="queryOneToOneResultMap" type="Order" autoMapping="true">  
  
<id column="oid" property="id"/>  
<result column="order\_number" property="orderNumber"/>  
  
<association property="user" javaType="User" autoMapping="true">  
  
<id column="id" property="id"/>  
</association>  
</resultMap>

2）一对多：  
<resultMap id="queryOneToManyResultMap" type="User" autoMapping="true">  
  
<id column="id" property="id"/>  
  
<collection property="orderList" ofType="Order" autoMapping="true">  
  
<id column="oid" property="id"/>  
</collection>  
</resultMap>  
3.注解实现增删改查：\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
@Select:查询  
@Insert:插入  
@Update:更新  
@Delete:删除  
4.注解实现自增主键回填：  
在添加的方法上使用注解：@Options(useGeneratedKeys = true,keyColumn = "主键字段名",keyProperty = "主键成员变量名")

5.注解实现动态sql:  
@SelectProvider(type = 工具类.class,method = "方法名")

[2beb5ff7e9e7405583940f8007ed1d41.png]: https://img-blog.csdnimg.cn/2beb5ff7e9e7405583940f8007ed1d41.png