接口的讲解

在这里之前我想童鞋们都学习过了springmvc。mybatis-plus。Springboot等一些框架

那么下面我们就整合这些框架

我们通过写crud这些接口

写接口的第一步就是引入pom文件
在pom文件里引入一下几种依赖

引入父级工程
thymeleaf导入模版工具类
SpringMVCjar包文件
热部署工具
lombok插件
测试包
引入jdbc包
引入数据库驱动
spring整合mybatis-plus
负责项目打包部署

<?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><!--引入父级工程--><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.4.5</version><relativePath/></parent><artifactId>jiekou</artifactId><version>1.0-SNAPSHOT</version><properties><maven.compiler.source>16</maven.compiler.source><maven.compiler.target>16</maven.compiler.target></properties><dependencies><!--thymeleaf导入模版工具类--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency><!--SpringMVCjar包文件--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!--热部署工具--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-devtools</artifactId><scope>runtime</scope><optional>true</optional></dependency><!--lombok插件--><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><!--测试包--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!--引入jdbc包--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-jdbc</artifactId></dependency><!--引入数据库驱动 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><!--spring整合mybatis-plus --><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.4.2</version></dependency></dependencies><!--负责项目打包部署--><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId><configuration><excludes><exclude><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></exclude></excludes></configuration></plugin><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><configuration><source>16</source><target>16</target></configuration></plugin></plugins></build></project>

pom文件引入依赖之后那么下一步就需要配置数据库 的连接以及我们配置的端口

server:port: 8090spring:datasource:url: jdbc:mysql://127.0.0.1:3306/jt?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&autoReconnect=true&allowMultiQueries=trueusername: rootpassword: wyproot123#整合SpringMVCthymeleaf:#设置页面前缀prefix: classpath:/templates/#设置页面后缀suffix: .html#是否使用缓存cache: falsemybatis-plus:type-aliases-package: com.jt.pojo#type-aliases-package: com.jtmapper-locations: classpath:/mappers/*.xml#开启驼峰映射configuration:map-underscore-to-camel-case: true#添加MP日志  打印执行的sql
logging:level:com.jt.mapper: debug

mapper文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.jt"></mapper>

首先我们要写一个实体类pojo，注意这里的属性一定要和数据库的表列相对应

package com.jt.pojo;import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;
import lombok.experimental.Accessors;import java.io.Serializable;@Data
@Accessors(chain = true)
@TableName("user")  //保证数据安全性和有效性必须序列化
public class User implements Serializable {@TableId(type = IdType.AUTO) //主键自增private Integer id;private String name;private Integer num;}

下一步我们就要写dao层结构

我们因为使用的是mybatis-plus所以我们在这里写的代码比较少这也就是框架的好处

package com.jt.mapper;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.jt.pojo.User;/*** @author :王闫彭* @date : 2023/5/28*/
public interface UseMapper extends BaseMapper<User> {
}

service层结构

首先写service接口

package com.jt.service;import com.jt.pojo.User;import java.util.List;public interface UserService {List<User> findAll();void insertUser(User user);void updateUser(User user);void deleteUserById(Integer id);
}

service的实现类

package com.jt.service;import com.jt.mapper.UserMapper;
import com.jt.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.List;@Service
public class UserServiceImpl implements UserService{@Autowiredprivate UserMapper userMapper;//mp的查询@Overridepublic List<User> findAll() {return userMapper.selectList(null);}//MP的方式实现入库@Overridepublic void insertUser(User user) {userMapper.insert(user);}//mp的更新@Overridepublic void updateUser(User user) {userMapper.updateById(user);}//mp的删除@Overridepublic void deleteUserById(Integer id) {userMapper.deleteById(id);}
}

controller层结构

package com.jt.controller;import com.jt.pojo.User;
import com.jt.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
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.ResponseBody;import java.util.List;@Controller
public class UserController {@Autowiredprivate UserService userService;@GetMapping("/findUser")@ResponseBodypublic List<User> findAjaxUser(){return userService.findAll();}@RequestMapping("/useraa/{id}/{name}/{num}")@ResponseBodypublic String insertUseraa(User user){userService.insertUser(user);return "添加成功";}@RequestMapping("/userbb/{id}/{name}")@ResponseBodypublic String updateUseraa(User user){userService.updateUser(user);return "更新成功";}@RequestMapping("/usercc/{id}")@ResponseBodypublic String deleteUsercc(@PathVariable Integer id){userService.deleteUserById(id);//重新发起请求..return "删除成功";}}

启动类

package com.jt;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;@SpringBootApplication
@MapperScan("com.jt.mapper")public class SpringBootRun {public static void main(String[] args) {SpringApplication.run(SpringBootRun.class,args);}
}