SpringBoot框架连接数据库实战（超详细）

SpringBoot框架用于实战（可直接下载源码进行拓展）

步骤：

1. 创建数据库mr_wen，新建两条测试数据
2. 创建SpringBoot项目
3. 编写代码块，并进行单元测试

   ---

   ---

   创建数据库mr_wen，新建两条测试数据

• create DATABASE mr_wen;
  use mr_wen;
  create table `product_category` (
      `category_id` int not null auto_increment,
      `category_name` varchar(64) not null ,
      `category_type` int not null  ,
      primary key (`category_id`)
  );

• 

    创建SpringBoot项目（图解）

     创建项目

     创建完成

     编写代码块

• 检查并导入依赖（pom.xml）

• <dependencies>
         <dependency>
              <groupId>org.springframework.boot</groupId>
              <artifactId>spring-boot-starter-web</artifactId>
          </dependency>
  
          <dependency>
              <groupId>org.springframework.boot</groupId>
              <artifactId>spring-boot-starter-test</artifactId>
              <scope>test</scope>
          </dependency>
  
          <dependency>
              <groupId>mysql</groupId>
              <artifactId>mysql-connector-java</artifactId>
          </dependency>
  
          <dependency>
              <groupId>org.springframework.boot</groupId>
              <artifactId>spring-boot-starter-data-jpa</artifactId>
          </dependency>
  
          <dependency>
              <groupId>org.projectlombok</groupId>
              <artifactId>lombok</artifactId>
          </dependency>
      </dependencies>
  

• 测试项目是否可运行
• 
• 
• 编写application.properties（用于连接数据库）

• Spring.dataSource.driver-class-name=com.mysql.cj.jdbc.Driver
  Spring.dataSource.url=jdbc:mysql://localhost:3306/mr_wen?serverTimezone=UTC&characterEncoding=utf-8&useSSL=false
  Spring.dataSource.username=root
  Spring.dataSource.password=root
  
  Spring.jpa:shop-sql:true
  
  

• com.example.demo目录下创建包名dataobject，并创建类ProductCategory实体类

• package com.example.demo.dataobject;
  
  import lombok.Data;
  
  import javax.persistence.Entity;
  import javax.persistence.GeneratedValue;
  import javax.persistence.GenerationType;
  import javax.persistence.Id;
  //需要idea安装lombok插件，也可以自行添加G/S方法，toStirng方法
  @Entity
  @Data
  public class ProductCategory {
  
      @Id
      @GeneratedValue(strategy = GenerationType.IDENTITY)
      private Integer categoryId;
  
  
      private String categoryName;
  
      private Integer categoryType;
  
  
  }
  

•  com.example.demo目录下创建包名dao，并创建类ProductCategoryDao持久层

• package com.example.demo.dao;
  
  import com.example.demo.dataobject.ProductCategory;
  import org.springframework.data.jpa.repository.JpaRepository;
  
  public interface ProductCategoryDao extends JpaRepository<ProductCategory,Integer> {
      List<ProductCategory> findByCategoryTypeIn(List<Integer> categoryTypeList);
  }

• 进行测试（写完程序进行单元测试可以随时检验代码的错误）

• package com.example.demo.dao;
  
  import com.example.demo.dataobject.ProductCategory;
  import org.junit.Assert;
  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;
  
  import java.util.Arrays;
  import java.util.List;
  
  import static org.junit.Assert.*;
  
  @RunWith(SpringRunner.class)
  @SpringBootTest
  public class ProductCategoryDaoTest {
  
      @Autowired
      private ProductCategoryDao productCategoryDao;
  
      /*查询*/
      @Test
      public void findOne(){
          ProductCategory productCategory=productCategoryDao.findById(1).get();
          Assert.assertNotNull(productCategory);
          System.out.println("productCategory = " + productCategory);
      }
  
      /*测试新增数据*/
      @Test
      public void saveTest(){
          ProductCategory productCategory=new ProductCategory();
          productCategory.setCategoryName("最佳科技榜单");
          productCategory.setCategoryType(1);
          productCategoryDao.save(productCategory);
      }
  
      /*测试更新*/
      @Test
      public void updateTest(){
          ProductCategory productCategory=new ProductCategory();
          productCategory.setCategoryId(2);
          productCategory.setCategoryName("科技榜单");
          productCategory.setCategoryType(10);
          productCategoryDao.save(productCategory);
      }
  
  
      @Test
      public void findByCategoryTypeInTest(){
          List<Integer>lists= Arrays.asList(1,2,3);
  
          List<ProductCategory> result=productCategoryDao.findByCategoryTypeIn(lists);
          Assert.assertNotEquals(0,result.size());
      }
  
  }

• com.example.demo目录下创建包名service，并service下创建impl包，接着创建类CategoryService，CategoryServiceImpl

• package com.example.demo.service;
  
  import com.example.demo.dataobject.ProductCategory;
  
  
  import java.util.List;
  
  public interface CategoryService {
  
      //根据Id查询
      public ProductCategory findOne(Integer caregoryId);
  
      //查询所有
      public List<ProductCategory>findAll();
  
      //根据编号的传入查询所有匹配数据
      public List<ProductCategory> findByCategoryTypeIn(List<Integer> categoryTypeList);
  
      //更新传入数据信息进行更新
      public ProductCategory save(ProductCategory productCategory);
  }
  

•  

• package com.example.demo.service.impl;
  
  import com.example.demo.dao.ProductCategoryDao;
  import com.example.demo.dataobject.ProductCategory;
  import com.example.demo.service.CategoryService;
  
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Service;
  
  import java.util.List;
  
  @Service
  public class CategoryServiceImpl implements CategoryService {
  
      @Autowired
      private ProductCategoryDao productCategoryDao;
  
      @Override
      public ProductCategory findOne(Integer caregoryId) {
          return productCategoryDao.findById(caregoryId).get();
      }
  
      @Override
      public List<ProductCategory> findAll() {
          return productCategoryDao.findAll();
      }
  
      @Override
      public List<ProductCategory> findByCategoryTypeIn(List<Integer> categoryTypeList) {
          return productCategoryDao.findByCategoryTypeIn(categoryTypeList);
      }
  
      @Override
      public ProductCategory save(ProductCategory productCategory) {
          return productCategoryDao.save(productCategory);
      }
  }
  

•  
•   接着还是要进行必要测试

• package com.wechat.sell.service.impl;
  
  import com.wechat.sell.dataobject.ProductCategory;
  import org.junit.Assert;
  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;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  import static org.junit.Assert.*;
  
  
  @RunWith(SpringRunner.class)
  @SpringBootTest
  public class CategoryServiceImplTest {
  
      @Autowired
      private CategoryServiceImpl categoryService;
  
      @Test
      public void findOne() throws Exception{
          ProductCategory productCategory=categoryService.findOne(1);
          System.out.println("productCategory = " + productCategory);
          Assert.assertEquals(1,new Integer(1),productCategory.getCategoryId());
      }
  
      @Test
      public void findAll() throws Exception{
          List<ProductCategory>productCategoryList=categoryService.findAll();
          for(ProductCategory productCategory:productCategoryList){
              System.out.println("================ = " + "================");
              System.out.println("productCategory = " + productCategory);
          }
          Assert.assertNotEquals(0,productCategoryList.size());
      }
  
      @Test
      public void findByCategoryTypeIn() throws Exception{
          List<ProductCategory>productCategoryList=categoryService.findByCategoryTypeIn( Arrays.asList(1,2,3));
          for(ProductCategory productCategory:productCategoryList){
              System.out.println("================ = " + "================");
              System.out.println("productCategory = " + productCategory);
          }
          Assert.assertNotEquals(0,productCategoryList.size());
  
      }
  
      @Test
      public void save() throws Exception{
          ProductCategory productCategory=new ProductCategory();
          productCategory.setCategoryType(2);
          productCategory.setCategoryName("黑科技榜单");
          ProductCategory productCategory1=categoryService.save(productCategory);
          System.out.println("productCategory1 = " + productCategory1);
          Assert.assertNotNull(productCategory1);
      }
  }

•  
• 

博客提供有源码，源码中加入了Logback日志框架，源码可用于项目中套用并自行拓展

源码：源码下载

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