本部落格 貓叔的部落格，轉載請申明出處
本系列教程為HMStrange專案附帶。
歷史文章
教程內容
備註：本系列開發工具均為IDEA
1、構建專案，選擇Lombok、Web、MySQL、MyBatis四個基本的Maven依賴。
大家可以看看pom檔案
<?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>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.myself.mybatis</groupId>
<artifactId>datademo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>datademo</name>
<description>Demo project for Spring Boot</description>
<properties>
<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>2.0.1</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</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>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
複製程式碼2、準備MySQL，這裡可以參考歷史文章的安裝MySQL環節，我新建了一個資料庫，針對這個專案，構建了一張簡單的表。
DDL
CREATE TABLE `t_msg` (
`id` int(11) NOT NULL,
`message` varchar(255) DEFAULT NULL COMMENT '資訊',
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
複製程式碼3、構建專案目錄，我構建了一個經典的web專案目錄結構，entity實體類、mapper對映、service介面、impl介面實現、controller業務訪問、resources/mapper包用於存放xml
4、填寫application.yml，預設生成不是yml，不過我覺得yml視覺效果好一些，就改了一下，我們需要填寫資料庫資訊，還有mybatis的資料庫對映地址，實體類地址
spring:
datasource:
url: jdbc:mysql://192.168.192.133:3306/datademo?characterEncoding=utf-8&useSSL=false
username: root
password: password
driver-class-name: com.mysql.cj.jdbc.Driver
mybatis:
mapper-locations: classpath*:mapper/*Mapper.xml
type-aliases-package: com.myself.mybatis.entity
複製程式碼5、構建資料庫對應的實體類TMsg，這個類放在entity
package com.myself.mybatis.entity;
import lombok.Data;
import java.io.Serializable;
/**
* Created by MySelf on 2019/4/9.
*/
@Data
public class TMsg implements Serializable {
private Integer id;
private String message;
}
複製程式碼6、構建對應的Mapper介面（其實就類似dao層），這裡與TMsgMapper.xml檔案對應關係
package com.myself.mybatis.mapper;
import com.myself.mybatis.entity.TMsg;
import org.apache.ibatis.annotations.Mapper;
/**
* Created by MySelf on 2019/4/9.
*/
@Mapper
public interface TMsgMapper {
public TMsg findById(Integer id);
}
複製程式碼<?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.myself.mybatis.mapper.TMsgMapper">
<select id="findById" resultType="com.myself.mybatis.entity.TMsg">
SELECT id,message from t_msg WHERE id = #{id}
</select>
</mapper>
複製程式碼我這邊就單純一個方法，大家可以擴充套件自己的方法。
7、service層與其實現，這個比較簡單，一般做過web專案的都瞭解
package com.myself.mybatis.service;
import com.myself.mybatis.entity.TMsg;
/**
* Created by MySelf on 2019/4/9.
*/
public interface TMsgService {
public TMsg findById(Integer id);
}
複製程式碼package com.myself.mybatis.service.impl;
import com.myself.mybatis.entity.TMsg;
import com.myself.mybatis.mapper.TMsgMapper;
import com.myself.mybatis.service.TMsgService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
/**
* Created by MySelf on 2019/4/9.
*/
@Service
public class TMsgServiceImpl implements TMsgService {
@Autowired
private TMsgMapper tMsgMapper;
@Override
public TMsg findById(Integer id) {
return tMsgMapper.findById(id);
}
}
複製程式碼8、controller層，我這邊構建了一個get方法，通過id獲取資訊。
package com.myself.mybatis.controller;
import com.myself.mybatis.entity.TMsg;
import com.myself.mybatis.service.TMsgService;
import org.apache.ibatis.annotations.Param;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* Created by MySelf on 2019/4/9.
*/
@RestController
@RequestMapping("/msg")
public class TMsgController {
@Autowired
private TMsgService tMsgService;
@GetMapping("/getMsg")
public String getMsg(@Param("id") Integer id){
TMsg tMsg = tMsgService.findById(id);
return tMsg.getMessage();
}
}
複製程式碼9、啟動專案，並使用Postman測試
10、專案下載地址
歡迎到HMStrange專案進行下載：github.com/UncleCatMyS…
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