Springboot连接数据库

好家伙，

 

这里使用的软件是IDEA 2021

1.新建项目

 

 

 

 

2.更改配置项目文件目录

更改前:

 

 更改后:

 

 

2.1.更改pom.xml文件

 

 

在该文件中添加:

    <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
    </dependency>    

 

 

2.2.更改配置application.properties文件

spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test    //按你说的数据库名字改
spring.datasource.username=root   //按你的的数据库用户名改,一般都是'root'
spring.datasource.password=root   //按你的的数据库密码改
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.max-idle=10
spring.datasource.max-wait=10000
spring.datasource.min-idle=5
spring.datasource.initial-size=5

server.port=8011
server.session.timeout=10
server.tomcat.uri-encoding=UTF-8

 

 

2.3.更改配置TestController文件:

 

 

代码如下:

package com.example.demo.controller;   //按文件的实际路径来写
 import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Map.Entry; import java.util.Set; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @RestController @RequestMapping("/mydb") public class TestController { @Autowired private JdbcTemplate jdbcTemplate; @RequestMapping("/getUsers") public List<Map<String, Object>> getDbType(){ String sql = "select * from appuser"; List<Map<String, Object>> list = jdbcTemplate.queryForList(sql); for (Map<String, Object> map : list) { Set<Entry<String, Object>> entries = map.entrySet( ); if(entries != null) { Iterator<Entry<String, Object>> iterator = entries.iterator( ); while(iterator.hasNext( )) { Entry<String, Object> entry =(Entry<String, Object>) iterator.next( ); Object key = entry.getKey( ); Object value = entry.getValue(); System.out.println(key+":"+value); } } } return list; } @RequestMapping("/user/{id}") public Map<String,Object> getUser(@PathVariable String id){ Map<String,Object> map = null; List<Map<String, Object>> list = getDbType(); for (Map<String, Object> dbmap : list) { Set<String> set = dbmap.keySet(); for (String key : set) { if(key.equals("id")){ if(dbmap.get(key).equals(id)){ map = dbmap; } } } } if(map==null) map = list.get(0); return map; } }

 

 

2.4.更改配置主启动程序DemoApplication文件

 

 

代码如下:

package com.example.demo;  //按文件的实际路径来写
 import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class DemoApplication { public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } }

 

 

3.mysql新建表

spring boot这边基本上搞定了,

前往mysql workbench

3.1.添加一个名为appuser的表

并在其中设置'id','name','password'等属性

中填一点数据用于测试

 

 

 

4.前往spring boot 中启动主程序

启动主程序DemoApplication

 

点击进入localhost:8011/mydb/getUsers

不出意外的话，应该是出不了什么意外了

 

 

 

搞定！！

 

That's all