SpringBoot2 Mybatis整合

前言:

由于之前学过SpringBoot,但是知识没有得到实践,近期手头的事也都忙完了,于是寻思着做一个微商城,使用SpringBoot+Mybatis搭建的后台,之前学习SpringBoot的时候属于小打小闹,学艺不精,导致用了整整一天才将这个架子搭好,通过这次搭建买个教训,把踩过的坑都记录下来,这样会大大节省以后开发的效率.

 

搭建环境:

1.开发工具: Intellij IDEA 2018.1.2

2.SpringBoot 2.0.5.RELEASE

3.jdk: 1.8

4. maven: 3.5.3

5.alibaba Druid 数据库连接池: 1.1.9

其他功能:

PageHelper 分页查询

源码地址:

https://github.com/godlikecheng/SpringBoot_MyBatis_frame

项目目录:

首先可根据项目目录将项目大体轮廓建出来(比如将文件夹和相关的文件建出来,内容暂时为空,后面讲解会补充)

项目搭建:

1.创建项目

2.添加基础依赖

3.依赖文件:

pom文件中的添加内容:

<?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>

    <groupId>kim.chengcheng</groupId>
    <artifactId>goods</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>goods</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
        <relativePath/>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <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>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.4</version>
        </dependency>


        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.datatype</groupId>
            <artifactId>jackson-datatype-joda</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-parameter-names</artifactId>
        </dependency>
        <!-- 分页插件 -->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.2.5</version>
        </dependency>
        <!-- 阿里巴巴的Druid数据库连接池 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.9</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

4.项目启动类

注意:@MapperScan("kim.chengcheng.goods.dao")这个注解非常的关键，这个对应了项目中mapper（dao）对应的包路径

package kim.chengcheng.goods;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;


/**
 * @作者：张宜成
 * @描述：SpringBoot主类-启动类
 */

@SpringBootApplication
@MapperScan("kim.chengcheng.goods.dao")
public class GoodsApplication {

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

5.在resource文件夹下创建application.yml

## 服务器端口号
server:
  port: 80

## 关于数据库参数的相关配置
spring:
    datasource:
        name: mysql_test
        type: com.alibaba.druid.pool.DruidDataSource
        #druid相关配置
        druid:
          #监控统计拦截的filters
          filters: stat
          driver-class-name: com.mysql.jdbc.Driver
          #基本属性
          url: jdbc:mysql://127.0.0.1:3306/mytest?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true
          username: root
          password: root
          #配置初始化大小/最小/最大
          initial-size: 1
          min-idle: 1
          max-active: 20
          #获取连接等待超时时间
          max-wait: 60000
          #间隔多久进行一次检测，检测需要关闭的空闲连接
          time-between-eviction-runs-millis: 60000
          #一个连接在池中最小生存的时间
          min-evictable-idle-time-millis: 300000
          validation-query: SELECT 'x'
          test-while-idle: true
          test-on-borrow: false
          test-on-return: false
          #打开PSCache，并指定每个连接上PSCache的大小。oracle设为true，mysql设为false。分库分表较多推荐设置为false
          pool-prepared-statements: false
          max-pool-prepared-statement-per-connection-size: 20

## MyBatis的相关配置
mybatis:
  # 映射文件位置
  mapper-locations: classpath:mapper/*.xml
  # 别名扫描包
  type-aliases-package: kim.chengcheng.goods.model
  # 输出SQL执行语句
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

## pagehelper分页相关配置
pagehelper:
    helperDialect: mysql
    reasonable: true
    supportMethodsArguments: true
    params: count=countSql
    returnPageInfo: check

6.创建数据库和表

CREATE DATABASE mytest;

CREATE TABLE t_user(
  userId INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
  userName VARCHAR(255) NOT NULL ,
  password VARCHAR(255) NOT NULL ,
  phone VARCHAR(255) NOT NULL
) ENGINE=INNODB AUTO_INCREMENT=1000 DEFAULT CHARSET=utf8;

7.创建实体类:(根据项目目录进行建java文件)

1.UserDomain.java

package kim.chengcheng.goods.model;

/**
 * @作者：张宜成
 * @描述：Model层
 */

public class UserDomain {

    private Integer userId;
    private String userName;
    private String password;
    private String phone;

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName == null ? null : userName.trim();
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password == null ? null : password.trim();
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone == null ? null : phone.trim();
    }
}

2.UserDao.java

package kim.chengcheng.goods.dao;

import kim.chengcheng.goods.model.UserDomain;
import org.springframework.stereotype.Repository;

import java.util.List;

/**
 * @作者：张宜成
 * @描述：DAO接口层
 */

@Repository
public interface UserDao {

    int insert(UserDomain record);

    List<UserDomain> selectUsers();
}

3.UserMapper.xml(mybatis映射文件)

注意:<mapper namespace="kim.chengcheng.goods.dao.UserDao"> 一定要对应自己dao所在的包路径

<?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="kim.chengcheng.goods.dao.UserDao" >
    <sql id="BASE_TABLE">
    t_user
  </sql>

    <sql id="BASE_COLUMN">
    userId,userName,password,phone
  </sql>

    <insert id="insert" parameterType="kim.chengcheng.goods.model.UserDomain">
        INSERT INTO
        <include refid="BASE_TABLE"/>
        <trim prefix="(" suffix=")" suffixOverrides=",">
            userName,password,
            <if test="phone != null">
                phone,
            </if>
        </trim>
        <trim prefix="VALUES(" suffix=")" suffixOverrides=",">
            #{userName, jdbcType=VARCHAR},#{password, jdbcType=VARCHAR},
            <if test="phone != null">
                #{phone, jdbcType=VARCHAR},
            </if>
        </trim>
    </insert>

    <select id="selectUsers" resultType="kim.chengcheng.goods.model.UserDomain">
        SELECT
        <include refid="BASE_COLUMN"/>
        FROM
        <include refid="BASE_TABLE"/>
    </select>

</mapper>

4.UserService.java

package kim.chengcheng.goods.service;

import com.github.pagehelper.PageInfo;
import kim.chengcheng.goods.model.UserDomain;

/**
 * @作者：张宜成
 * @描述：Service接口层
 */

public interface UserService {

    int addUser(UserDomain user);

    PageInfo<UserDomain> findAllUser(int pageNum, int pageSize);
}

5.UserServiceimpl.java

package kim.chengcheng.goods.service.impl;

import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import kim.chengcheng.goods.dao.UserDao;
import kim.chengcheng.goods.model.UserDomain;
import kim.chengcheng.goods.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * @作者：张宜成
 * @描述：Service实现层-ServiceImpl
 */

@Service(value = "userService")
public class UserServiceImpl implements UserService {

    @Autowired
    private UserDao userDao;

    @Override
    public int addUser(UserDomain user) {
        return userDao.insert(user);
    }

    /*
     * 这个方法中用到了开头配置依赖的分页插件pagehelper
     * 很简单，只需要在service层传入参数，然后将参数传递给一个插件的一个静态方法即可；
     * pageNum 开始页数
     * pageSize 每页显示的数据条数
     * */
    @Override
    public PageInfo<UserDomain> findAllUser(int pageNum, int pageSize) {
        //将参数传给这个方法就可实现物理分页.
        PageHelper.startPage(pageNum, pageSize);
        List<UserDomain> userDomains = userDao.selectUsers();
        PageInfo result = new PageInfo(userDomains);
        return result;
    }
}

6.UserController.java

package kim.chengcheng.goods.controller;

import com.github.pagehelper.PageHelper;
import kim.chengcheng.goods.model.UserDomain;
import kim.chengcheng.goods.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;

/**
 * @作者：张宜成
 * @描述：Controller层
 */

@Controller
@RequestMapping(value = "/user")
public class UserController {

    @Autowired
    private UserService userService;

    @ResponseBody
    @PostMapping("/add")
    public int addUser(UserDomain user){
        return userService.addUser(user);
    }

    @ResponseBody
    @GetMapping("/all")
    public Object findAllUser(
            @RequestParam(name = "pageNum", required = false, defaultValue = "1")
                    int pageNum,
            @RequestParam(name = "pageSize", required = false, defaultValue = "10")
                    int pageSize){
        return userService.findAllUser(pageNum,pageSize);
    }

}

项目最终结构就是博客开头给的项目目录.在此SpringBoot2 + MyBatis的后台搭建过程完成了,下面就是进行测试是否搭建成功.

 

启动项目

测试:

在此则查看到数据库中的数据已经成功查询了出来,则表示查询成功.