springboot+mybatis+mysql搭建项目简明demo

项目所需目录结构

pom.xml文件配置

<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>com.MyProject</groupId>
    <artifactId>Test</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>Test</name>
    <description>Test project for spring boot mybatis</description>
  
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
    </parent>
    
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <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>
        </dependency>
            
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.9.6</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.6</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.9.6</version>
        </dependency>
    </dependencies>
    
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <!-- <configuration>
                <jvmArguments>
                    -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005
                </jvmArguments>
                </configuration>  -->
            </plugin>
        </plugins>
    </build>
</project>

application.properties文件配置

spring.datasource.url=jdbc:mysql://localhost:3306/mydb?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true&useSSL=false&allowPublicKeyRetrieval=true
spring.datasource.username=root
spring.datasource.password=123
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.max-idle=10
spring.datasource.max-wait=1000
spring.datasource.min-idle=5
spring.datasource.initial-size=5
server.port=8886
server.session.timeout=10
server.tomcat.uri-encoding=UTF-8
mybatis.mapper-locations=classpath:mapper/*.xml

MyApplication.java入口文件配置

package com.myproject.FirstProject;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class MyApplication {

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

User.xml测试mapper配置文件

<?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.myproject.FirstProject.dao.mydao">
    <select id="GetUserbyId" resultType="map" parameterType="int">
        select * from test where id=#{id}
    </select>
</mapper>

其中namespace指明的是你的dao接口文件

编写dao接口，mydao.java

package com.myproject.FirstProject.dao;

import java.util.List;
import java.util.Map;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;

@Mapper
public interface mydao {
	List<Map> GetUserbyId(@Param("id") Integer id);
}

dao的作用其实就是将mapper的xml和java中的类做一个耦合映射

编写service层，myservice.java

package com.myproject.FirstProject.service;

import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.myproject.FirstProject.dao.mydao;

@Service
public class myservice {
	@Autowired
	mydao dao;
	
	public List<Map> test(Integer id) {
		return dao.GetUserbyId(id);
	}
}

编写控制器，mycontroller.java

package com.myproject.FirstProject.controller;

import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import com.myproject.FirstProject.service.myservice;

@RestController
public class mycontroller {
	@Autowired
	myservice serv;

    @RequestMapping("/myapitest")
	public List<Map> myapitest(@RequestParam("id") int id) {
		return serv.test(id);
	}
}