Java 微服务 day02 源代码 SpringBoot 实战开发整合Mybatis（数据库连接池），通用Mapper整合，业务层整合

Posted 2021-08-22 蓝盒子bluebox

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Java 微服务day01 源代码 SpringBoot的SpringMVC快速入门（一）
Java 微服务 day01 源代码 Java的配置（二）
Java 微服务 day02 源代码 SpringBoot 属性注入自动配置（一）
Java 微服务 day02 源代码 SpringBoot 实战开发（二）创建相关数据库，搭建服务，搭建普通工程，设置访问后缀以及端口号
Java 微服务 day02 源代码 SpringBoot 实战开发（三）SpringMVC高级配置：拦截器：HandlerExecutionChain
Java 微服务 day02 源代码 SpringBoot 实战开发（四）整合JDBC和事务（数据库连接池）
Java 微服务 day02 源代码 SpringBoot 实战开发（五）整合Mybatis（数据库连接池），通用Mapper整合，业务层整合

一、整合Mybatis

1、配置Mybatis

（1）配置启动器

 <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>

（2）配置驼峰和别名包

# 配置驼峰
mybatis:
  configuration:
    map-underscore-to-camel-case: true
  type-aliases-package: com.itzheng.pojo #配置别名包
  #mapper-locations: mapper/*.xml

（3）配置mapper扫描器

package com.itzheng;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.itzheng.mapper")
public class BootDemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(BootDemoApplication.class,args);
    }
}

二、通用Mapper整合

1、引入依赖

（1）在pom.xml当中

		 <!--通用Mapper-->
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.0.3</version>
        </dependency>

（2）引入的通用Mapper有一些配置就不需要了

<?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.itzheng.demo</groupId>
    <artifactId>springboot-demo</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <parent>
        <artifactId>spring-boot-starter-parent</artifactId>
            <groupId>org.springframework.boot</groupId>
        <version>2.0.4.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!--数据库驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--通用Mapper-->
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.0.3</version>
        </dependency>

    </dependencies>

</project>

（3）驼峰也会默认开启，所以也不需要配置了

全部

server:
  port: 8088
  servlet:
    path: /
logging:
  level:
    com.itzheng: debug
    #org.springframework: debug

spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/itzheng
    username: root
    password: root
mybatis:
  type-aliases-package: com.itzheng.pojo #配置别名包
  #mapper-locations: mapper/*.xml

（4）启动类BootDemoApplication改变扫描包通过tk.mybatis.mapper扫描

package com.itzheng;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import tk.mybatis.spring.annotation.MapperScan;

@SpringBootApplication
@MapperScan("com.itzheng.mapper")
public class BootDemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(BootDemoApplication.class,args);
    }
}

2、创建UserMapper接口并继承Mapper会自动具备一系列的对数据的方法

package com.itzheng.mapper;
import com.itzheng.pojo.User;
import tk.mybatis.mapper.common.Mapper;
public interface UserMapper  extends Mapper<User> {

}

3、在对应的实体类上添加注解实现SQL语句的自动生成

package com.itzheng.pojo;

import lombok.Data;
import tk.mybatis.mapper.annotation.KeySql;

import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.Transient;
import java.util.Date;

@Data
@Table(name="tb_user")
public class User {
    //id
    @Id
    @KeySql(useGeneratedKeys = true)  //useGeneratedKeys主键自增
    private Long id;
    //用户名
    private String userName;
    //密码
    private String password;
    //姓名
    private String name;
    //年龄
    private Integer age;
    //性别 1、男性  2、女性
    private Integer sex;
    //出生日期
    private Date birthday;
    //创建时间
    private Date created;
    //更新时间
    private Date updated;
    //备注

    private String note;

    @Transient  //Transient当前属性不是要生成SQL的的属性
    private int aaaa;

}

4、测试

（1）在pom.xml当中引入test

  <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
   </dependency>

（2）创建测试类UserMapperTest

package com.itzheng.mapper;

import com.itzheng.pojo.User;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class UserMapperTest {

    @Autowired
    private UserMapper userMapper;

    @Test
    public void testQuery(){
        User user = userMapper.selectByPrimaryKey(8L);
        System.out.println("User = " +user);
    }

}

数据库当中添加一些数据

INSERT INTO `tb_user` VALUES ('19', 'zhangsan', '123', 'zhangsan123', '12', '1', '2021-06-14', '1', '2021-06-29 18:21:50', '2021-06-30 18:21:53');

运行测试类

查询的结果

三、业务层整合

1、创建UserService

package com.itzheng.service;
import com.itzheng.mapper.UserMapper;
import com.itzheng.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
@Service
public class UserService {
    @Autowired
    private UserMapper userMapper;//注入usermapper接口
    //根据id查询的方法
    public User queryById(Long id){
        return userMapper.selectByPrimaryKey(id);
    }
    //插入数据的方法
    @Transactional  //添加事务
    public void insertUser(User user){
        userMapper.insert(user);
    }
}

2、运行测试，

（1）修改HelloController

package com.itzheng.web;

import com.itzheng.pojo.User;
import com.itzheng.service.UserService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@Slf4j
@RestController
@RequestMapping("user")
public class HelloController {

    @Autowired
    private UserService userService;

    @GetMapping("{id}")
    public User hello(@PathVariable("id") Long id){
        return userService.queryById(id);
    }

}

（2）运行项目

访问路径http://localhost:8088/user/1
1号

{
	"id":1,
	"userName":"zhangsan",
	"password":"123",
	"name":"zhangsan123",
	"age":12,
	"sex":1,
	"birthday":"2021-06-13T16:00:00.000+0000",
	"created":"2021-06-29T10:21:50.000+0000",
	"updated":"2021-06-30T10:21:53.000+0000",
	"note":null
}

2号

项目全部代码
https://download.csdn.net/download/qq_44757034/19894410