SpringBoot框架用于实战（可直接下载源码进行拓展）

步骤：

创建数据库mr_wen，新建两条测试数据
创建SpringBoot项目
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);
    }
}