Mybatis(六)

一、目录结构

二、代码

1、AccountDao

package cn.bijian.dao;


import cn.bijian.model.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;

public interface AccountDao {
   /*
       查询所有账户，采用延迟加载(一对一)
    */
    @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(column = "uid",property = "user",one = @One(select = "cn.bijian.dao.UserDao.findById",fetchType = FetchType.LAZY))
    })
    List<Account> findAll();

    /*
        根据uid查询Account(一对多)
     */
    @Select("select * from account where uid=#{id}")
    List<Account> findByUid(Integer id);
}

2、UserDao

package cn.bijian.dao;

import cn.bijian.model.User;
import org.apache.ibatis.annotations.*;
import org.apache.ibatis.mapping.FetchType;

import java.util.List;

@CacheNamespace(blocking = true)//基于注解方式实现配置二级缓存
public interface UserDao {
    /*
    查询所有用户，采用延迟加载(一对多)
     */
    @Select("select * from user")
    @Results(id = "userMap",value = {
            @Result(id = true,column = "id",property = "id"),
            @Result(column = "id",property = "id"),
            @Result(column = "username",property = "username"),
            @Result(column = "sex",property = "sex"),
            @Result(column = "address",property = "address"),
            @Result(column = "birthday",property = "birthday"),
            @Result(column = "id",property = "accounts",many = @Many(select = "cn.bijian.dao.AccountDao.findByUid",fetchType = FetchType.LAZY))
    })
    List<User> findAll();
    /*
    根据id查询用户
     */
    @Select("select * from user where id=#{id}")
    @ResultMap("userMap")
    User findById(Integer id);
    /*
    保存操作
     */
    @Insert("insert into user(username,sex,birthday,address) values(#{username},#{sex},#{birthday},#{address})")
    @SelectKey(keyProperty = "id",keyColumn = "id",resultType = Integer.class,before = false,statement = {"select last_insert_id()"})
    int saveUser(User user);
    /*
    更新操作
     */
    @Update("update user set username=#{username},address=#{address},sex=#{sex},birthday=#{birthday} where id=#{id}")
    int updateUser(User user);
    /*
    删除操作
     */
    @Delete("delete from user where id=#{id}")
    int deleteUser(Integer id);
    /*
    使用聚合函数查询
     */
    @Select("select count(*) from user")
    int findTotal();
    /*
    模糊查询
     */
    @Select("select * from user where address like #{address}")
    List<User> findByAddress(String address);
}

3、Account

package cn.bijian.model;

import java.io.Serializable;

public class Account implements Serializable {
    private Integer id;
    private Integer uid;
    private Double money;
    private 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;
    }

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", uid=" + uid +
                ", money=" + money +
                ", user=" + user +
                '}';
    }
}

4、User

package cn.bijian.model;

import java.io.Serializable;
import java.util.Date;
import java.util.List;

public class User implements Serializable {
    private Integer id;
    private String username;
    private Date birthday;
    private String sex;
    private String address;
    private List<Account> 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 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;
    }

    public List<Account> getAccounts() {
        return accounts;
    }

    public void setAccounts(List<Account> accounts) {
        this.accounts = accounts;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", username='" + username + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                ", accounts=" + accounts +
                '}';
    }
}

5、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>
    <settings>
        <!--开启二级缓存-->
        <setting name="cacheEnabled" value="true"/>
    </settings>
    <environments default="mysql">
        <environment id="mysql">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">  <!--连接池-->
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTC"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <package name="cn.bijian.dao"/>
    </mappers>
</configuration>

6、MybatisTest

package cn.bijian;

import cn.bijian.dao.UserDao;
import cn.bijian.model.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.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.io.InputStream;
import java.util.Date;
import java.util.List;


public class MybatisTest {
    private InputStream in;
    private SqlSessionFactory sessionFactory;
    private SqlSession session;
    private UserDao userDao;

    @Before
    public void init() throws IOException {
        in = Resources.getResourceAsStream("SqlMapConfig.xml");
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        sessionFactory = builder.build(in);
        session = sessionFactory.openSession();
        userDao = session.getMapper(UserDao.class);
    }

    @After
    public void destroy() throws IOException {
        session.commit();
        session.close();
        in.close();
    }
    /*
        一对多，延迟加载
    */
    @Test
    public void testFindAll(){
        List<User> users = userDao.findAll();
        for (User user:users) {
            System.out.println(user);
        }
    }

    @Test
    public void testFindById(){
        User user = userDao.findById(41);
        System.out.println(user);
    }

    @Test
    public void testSaveUser(){
        User user = new User();
        user.setUsername("aaa");
        user.setSex("男");
        user.setBirthday(new Date());
        user.setAddress("兰州");
        int res = userDao.saveUser(user);
        System.out.println(res);
        System.out.println(user.getId());
    }

    @Test
    public void testUpdateUser(){
        User user = userDao.findById(67);
        user.setUsername("gggg");
        int res = userDao.updateUser(user);
        System.out.println(res);
    }

    @Test
    public void testDeleteUser(){
        int res = userDao.deleteUser(67);
        System.out.println(res);
    }

    @Test
    public void testFindTotal(){
        int total = userDao.findTotal();
        System.out.println(total);
    }

    @Test
    public void testFindByAddress(){
        List<User> users = userDao.findByAddress("%兰州%");
        for (User user:users) {
            System.out.println(user);
        }
    }
}

7、MybatisTest2

package cn.bijian;

import cn.bijian.dao.AccountDao;
import cn.bijian.model.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.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;


public class MybatisTest2 {
    private InputStream in;
    private SqlSessionFactory sessionFactory;
    private SqlSession session;
    private AccountDao accountDao;

    @Before
    public void init() throws IOException {
        in = Resources.getResourceAsStream("SqlMapConfig.xml");
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        sessionFactory = builder.build(in);
        session = sessionFactory.openSession();
        accountDao = session.getMapper(AccountDao.class);
    }

    @After
    public void destroy() throws IOException {
        session.commit();
        session.close();
        in.close();
    }
    /*
        一对一，延迟加载
     */
    @Test
    public void testFindAll(){
        List<Account> accounts = accountDao.findAll();
        for (Account account:accounts) {
            System.out.println(account);
        }
    }

    @Test
    public void testFindByUid(){
        List<Account> accounts = accountDao.findByUid(41);
        for (Account account:accounts) {
            System.out.println(account);
        }
    }
}