Spring整合Mybatis操作数据库

作为一个新技术，Spring在对老技术的支持上已经是非常全面，而Mybatis同时向Spring提供了对应的依赖，以保证能够完美兼容

依赖导入

需要引入的依赖有：
spring-context | spring-jdbc | mybatis | mybatis-spring | mysql-connector-java | druid | lombok

搭建三层架构

实现步骤

1. 配置一个名叫jdbc.properties的数据源用来存放关于jdbc的信息

2. 配置类

   1. Spring配置类

      1. 使用@Configurable声明
      2. 设置扫描com.itheima下的文件
      3. 引入对应的数据源（jdbc.properties）
      4. 导入Jdbc配置类和Mybatis配置类

   2. Jdbc配置类

      这个类主要是将数据源中的数据取出并通过druid的DataSource方法使用

   3. MybatisConfig

      将Mybatis的xml简写

3. domain层

   pojo层Getter、Setter

4. Dao层

   利用注解设置增删改查方法

5. Service层

   设置Service层接口和实现类

   1. 实现类中

      利用自动装配的dao层，将参数传到Service中

6. 运行类

具体实现

数据库

配置类

SpringConfig

package com.itheima.config;

import org.springframework.beans.factory.annotation.Configurable;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.PropertySource;

/*创建spring配置类*/
@Configurable

/*扫描包路径*/
@ComponentScan("com.itheima")
/*引入配置文件*/
@PropertySource("classpath:jdbc.properties")
/*导入对应的Jdbc配置*/
@Import({JdbcConfig.class,MybatisConfig.class})
public class SpringConfig {
    
}

JdbcConfig

package com.itheima.config;

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;

import javax.sql.DataSource;

public class JdbcConfig {
    @Value("${jdbc.driver}")
    private String driver;

    @Value("${jdbc.url}")
    private String url;

    @Value("${jdbc.username}")
    private String username;

    @Value("${jdbc.password}")
    private String password;

    @Bean
    public DataSource dataSource(){
        DruidDataSource ds=new DruidDataSource();
        ds.setDriverClassName(driver);
        ds.setUrl(url);
        ds.setUsername(username);
        ds.setPassword(password);
        return ds;
    }
}

MybatisConfig

package com.itheima.config;

import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;

import javax.sql.DataSource;

public class MybatisConfig {
    @Bean
    public SqlSessionFactoryBean sqlSessionFactoryBean(DataSource dataSource){
        SqlSessionFactoryBean ssf=new SqlSessionFactoryBean();
        /*设置类型包*/
        ssf.setTypeAliasesPackage("com.itheima.domain");
        ssf.setDataSource(dataSource);
        return ssf;
    }
    @Bean
    public MapperScannerConfigurer mapperScannerConfigurer(){
        MapperScannerConfigurer msc=new MapperScannerConfigurer();
        msc.setBasePackage("com.itheima.dao");
        return msc;
    }
}

domain层

Account

package com.itheima.domain;

import java.io.Serializable;

public class Account {
    private Integer id;
    private String name;
    private Double money;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Double getMoney() {
        return money;
    }

    public void setMoney(Double money) {
        this.money = money;
    }

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

Dao层

接口AccountDao

package com.itheima.Dao;

import com.itheima.domain.Account;
import org.apache.ibatis.annotations.*;

import java.util.List;

public interface AccountDao {
    @Insert("insert into tbl_account(id,name,money)values(#{id},#{name},#{money})")
    void save(Account account);

    @Delete("delete from tbl_account where id = #{id} ")
    void delete(Integer id);

    @Update("update tbl_account set name = #{name} , money = #{money} where id = #{id} ")
    void update(Account account);

    @Select("select * from tbl_account")
    List<Account> selectAll();

    @Select("select * from tbl_account where id = #{id} ")
    Account findById(Integer id);
}

service层

接口AccountService

package com.itheima.service;

import com.itheima.domain.Account;

import java.util.List;


public interface AccountService {
    void save(Account account);

    void delete(int id);

    void update(Account account);

    List<Account> selectAll(Account account);
}

实现类AccountServiceImpl

package com.itheima.service.impl;

import com.itheima.Dao.AccountDao;
import com.itheima.domain.Account;
import com.itheima.service.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;


@Service
public class AccountServiceImpl implements AccountService {
    @Autowired
    private AccountDao accountDao;

    /*新增*/
    public void save(Account account){
        accountDao.save(account);
    }

    /*删除*/
    @Override
    public void delete(int id) {
        accountDao.delete(id);
    }

    /*修改*/
    public void update(Account account){
        accountDao.update(account);
    }
    
    /*查找*/
    @Override
    public List<Account> selectAll(Account account) {
        return accountDao.selectAll();
    }
}

运行类

package com.itheima;

import com.itheima.config.SpringConfig;
import com.itheima.domain.Account;
import com.itheima.service.AccountService;
import com.itheima.service.impl.AccountServiceImpl;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import java.util.List;

public class App {
    public static void main(String[] args) {
        ApplicationContext crx=new AnnotationConfigApplicationContext(SpringConfig.class);
        AccountService accountService=crx.getBean(AccountService.class);

        /*新增数据*/
        Account account=new Account();
        account.setId(3);
        account.setMoney(400.0);
        account.setName("王五");
        accountService.save(account);
        
        /*删除数据*/
        accountService.delete(1);

        /*修改数据*/
        Account account=new Account();
        account.setId(3);
        account.setName("赵六");
        account.setMoney(500.0);
        accountService.update(account);

        /*查找全部*/
        Account account=new Account();
        List<Account> list1=accountService.selectAll(account);
        System.out.println(list1);
    }
}