SpringBoot

Posted Maggieq8324的博客

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了SpringBoot相关的知识,希望对你有一定的参考价值。

前言

Mybatis是一个半自动化ORM(Object Relation Mapping)框架, 之所以说Mybatis半自动化,是因为SQL语句需要用户自定义,SQL的解析,执行等工作由Mybatis执行,这里记录下SpringBoot 整合Mybatis的案例。


环境

SpringBoot2.53 + Mybatis2.2.0


具体实现

项目结构

  • 项目结构如下所示

项目配置

  • pom.xml
<!-- web -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

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

<!-- mysql -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>

<!-- mybatis -->
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.2.0</version>
</dependency>

<!-- lombok -->
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
</dependency>
  • application.yml
spring:
  application:
    name: mybatis-learn
  # 文件编码 UTF8
  mandatory-file-encoding: UTF-8
  # 数据源配置,请修改为你项目的实际配置
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/cms?useSSL=false&serverTimezone=UTC&characterEncoding=UTF8
    username: root
    password: sunday

# mybatis配置(顶头开始写,否则读取不到)
mybatis:
  # mapper路径位置
  mapper-locations: classpath:mapper/*.xml
  configuration:
    # 开启下划线转驼峰
    map-underscore-to-camel-case: true

server:
  port: 8083
  • Table
CREATE TABLE `product` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `title` varchar(100) COLLATE utf8_unicode_ci DEFAULT NULL,
  `create_time` datetime DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci

实现代码

  • 启动类
@SpringBootApplication
@MapperScan(basePackages = {"com.coisini.mybatislearn.mapper"}) // 扫描的mapper
public class MybatisLearnApplication {

    public static void main(String[] args) {
        SpringApplication.run(MybatisLearnApplication.class, args);
    }

}
  • ProductController.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;

@RequestMapping("/product")
@RestController
public class ProductController {

    @Autowired
    private ProductService productService;

    /**
     * 查询Products
     * @return
     */
    @GetMapping("/select")
    public List<Product> selectProducts() {
        return productService.getProducts();
    }

	/**
     * 查询Products
     * @return
     */
    @GetMapping("/select1")
    public List<Product> getProducts1() {
        return productService.getProducts1();
    }

    /**
     * 插入product
     * @return
     */
    @GetMapping("/insert")
    public long insertProduct() {
        return productService.insertProduct();
    }

}
  • ProductService.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;

@Service
public class ProductService {

    @Autowired
    private ProductMapper productMapper;

    /**
     * 查询products
     * @return
     */
    public List<Product> getProducts() {
        return productMapper.getProducts();
    }

	/**
     * 查询products
     * @return
     */
    public List<Product> getProducts1() {
        return productMapper.getProducts1();
    }

    /**
     * 插入product
     * @return
     */
    public long insertProduct() {
        Product product = new Product();
        product.setTitle("NewProduct");

        productMapper.insertProduct(product);
        return product.getId();
    }
}
  • ProductMapper.java
import org.springframework.stereotype.Repository;
import java.util.List;

@Repository
public interface ProductMapper {

    /**
     * 查询products
     * @return
     */
    List<Product> getProducts();

	/**
     * 查询products
     * 注解编写sql
     * @return
     */
    @Select("select * from product")
    List<Product> getProducts1();

    /**
     * 插入product
     * @param product
     * @return
     */
    long insertProduct(Product product);

}
  • Product.java
import lombok.Getter;
import lombok.Setter;
import java.util.Date;

@Getter
@Setter
public class Product {

    private Integer id;

    private String title;

    private Date createTime;

}
  • ProductMapper.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.coisini.mybatislearn.mapper.ProductMapper">
    <resultMap id="BaseResultMap" type="com.coisini.mybatislearn.model.Product">
        <id column="id" property="id"/>
        <result column="title" property="title"/>
        <result column="create_time" property="createTime"/>
    </resultMap>

    <select id="getProducts" resultMap="BaseResultMap">
        select * from product
    </select>

	<!-- useGeneratedKeys="true" 通过jdbc getGeneratedKeys方法获取主键 -->
	<!-- keyProperty="id" 映射到resultMap id 属性上 -->
    <insert id="insertProduct" useGeneratedKeys="true" keyProperty="id"
            parameterType="com.coisini.mybatislearn.model.Product">
        INSERT INTO product(title) VALUES (#{title})
    </insert>
</mapper>
  • 注意事项
1.mapper-namespace需要与Mapper接口对应
2.mapper接口文件名最好与Mybatis的映射文件名一样
2.标签中的id必须与mapper接口中的方法名一致

测试


- End -
梦想是咸鱼
关注一下吧
以上为本篇文章的主要内容,希望大家多提意见,如果喜欢记得点个推荐哦
作者:Maggieq8324
本文版权归作者和博客园共有,欢迎转载,转载时保留原作者和文章地址即可。

以上是关于SpringBoot的主要内容,如果未能解决你的问题,请参考以下文章

SpringBoot中表单提交报错“Content type ‘application/x-www-form-urlencoded;charset=UTF-8‘ not supported“(代码片段

Spring boot:thymeleaf 没有正确渲染片段

11SpringBoot-CRUD-thymeleaf公共页面元素抽取

学习小片段——springboot 错误处理

springboot 底层点的知识

springboot 底层点的知识