springboot项目搭建，查找一个User类信息，mysql前缀索引原理

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”>

4.0.0

com.rosam

ywt

1.0-SNAPSHOT

org.apache.maven.

《一线大厂Java面试题解析+后端开发学习笔记+最新架构讲解视频+实战项目源码讲义》

【docs.qq.com/doc/DSmxTbFJ1cmN1R2dB】 完整内容开源分享

plugins

maven-war-plugin

2.6

false

org.springframework.boot

spring-boot-maven-plugin

org.springframework.boot

spring-boot-starter-parent

1.4.3.RELEASE

UTF-8

1.7

org.springframework.boot

spring-boot-starter-web

org.mybatis.spring.boot

mybatis-spring-boot-starter

1.3.1

mysql

mysql-connector-java

runtime

在看application.properties中配置mysql，和mybatis中的mapper路径，和实体路径（resources文件夹就可）

#数据库设置

spring.datasource.driver-class-name=com.mysql.jdbc.Driver

spring.datasource.url=jdbc:mysql://localhost:3306/ywttest

spring.datasource.username=root

spring.datasource.password=root

#mybatis_config

mybatis.mapper-locatiOns=classpath:mapper/*.xml

mybatis.type-aliases-package=com.rosam.ywttest.entity

controller层的代码（com.rosam.ywttest.controller）

package com.rosam.ywttest.controller;

import com.rosam.ywttest.entity.User;

import com.rosam.ywttest.service.YwtService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import javax.xml.ws.Action;

@Controller

public class YwtController {

@Autowired

private YwtService ywtService;

@RequestMapping("/ywt/{id}")

public void test(@PathVariable int id){

User user=ywtService.find(id);

System.out.println(user.getName());

}

}

service层的代码：(com.rosam.ywttest.service)

package com.rosam.ywttest.service;

import com.rosam.ywttest.dao.YwtDAO;

import com.rosam.ywttest.entity.User;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

@Service

public class YwtService {

@Autowired

private YwtDAO ywtDAO;

public User find(int id){

User user=ywtDAO.find(id);

return user;

}

}