springboot+mysql 简单查询操作

一、项目的分层

 

 

 1、controller层内容

　　

package com.dream.controller;



import com.dream.pojo.Users;
import com.dream.service.user.UsersService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;


import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

@Controller
public class PageController {
    //导入UsersService的包
    @Autowired
    private UsersService usersService;

    @RequestMapping("/index")
    public String index(){

        return "index";
    }

    @RequestMapping("/login")
    public String login(){
        return "/subpage/login";
    }

    /*
    登录验证
     */
    @RequestMapping("/unLogin")
//    @ResponseBody
    public String unLogin(HttpServletRequest request, Model model, HttpSession session){
        String uname=request.getParameter("username");
//        System.out.println("uname====>"+uname);
        String password = request.getParameter("password");
        Users byId = usersService.getById(uname);
        //设置session的值是为了使用thymeleaf在前端的调用不写报错
        session.setAttribute("all",byId);
        System.out.println(byId);
        if(byId==null){
            model.addAttribute("msg","密码错误");

            return "/subpage/login";


        }
        return "redirect:/index";
    }


}

2、mapper层

package com.dream.mapper;

import com.dream.pojo.Users;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;


@Mapper
@Repository
public interface UsersMapper {
    Users getById(String StuNumber);
}

3、pojo层

package com.dream.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.stereotype.Service;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Users {
    private int uId;
    private String uName;
    private String uPassword;
    private String uEmail;
    private String uTelephone;
    private int uFans;
    private int videoid;
    private String uhd;
    private int BlogId;
    private int Fabulous;
    private int EmId;
    private int DeleCommentNum;
    private int DeleblogNum;
    private int BlogNumber;
    private int videoNumber;
    private int Coin;
    private String BankCard;
    private String Classr;
    private String StuNumber;
    private String AdminId;
    private int Blacklistl;
    private String StateId;
}

4、service层里的user包UsersService

package com.dream.service.user;

import com.dream.pojo.Users;
import org.springframework.stereotype.Service;


@Service
public interface UsersService {
    Users getById(String StuNumber);

}

4.2、service层里的user包里的impl包UsersServiceImpl

package com.dream.service.user.impl;


import com.dream.mapper.UsersMapper;
import com.dream.pojo.Users;
import com.dream.service.user.UsersService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;


@Service
public class UsersServiceImpl implements UsersService {
    @Autowired
    private UsersMapper usersMapper;

    @Override
    public Users getById(String StuNumber) {
        return usersMapper.getById(StuNumber);
    }
}

5、resources里的mapper

<?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.dream.mapper.UsersMapper">

    <select id="getById" resultType="Users">
        select * from users where StuNumber=#{StuNumber};
    </select>
</mapper>

6、application.YML

spring:
  　　datasource:
    　　　　driver-class-name: com.mysql.cj.jdbc.Driver
    　　　　type: com.alibaba.druid.pool.DruidDataSource
    　　　　url: jdbc:mysql://localhost:3306/wuye_db?characterEncoding=utf8&useUnicode=true
    　　　　username: root
    　　　　password: root
server:
  　　port: 8080
mvc:
  　　static-path-pattern: /static/**

mybatis:
  　　type-aliases-package: com.cc.test2.pojo
  　　mapper-locations: classpath:mapper/*.xml

spring.thymeleaf.prefix: classpath:/templates/
spring.thymeleaf.suffix: .html

 7.POM.XML

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.cc</groupId>
    <artifactId>Test2</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>Test2</name>
    <description>Test2</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.2</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </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>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.14</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-test</artifactId>
            <version>2.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>5.8.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>


  



        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>


    </dependencies>



    <build>


        <resources>
<!--            <resource>-->
<!--                <directory>src/main/java</directory>-->
<!--                <includes>-->
<!--                    <include>**/*.xml</include>-->
<!--                </includes>-->
<!--            </resource>-->

            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.yml</include>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.yml</include>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>

        </resources>



        <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>
        </plugins>
    </build>

</project>