Springboot链接数据库 并curd

本人创建的maven项目

首先我们要添加数据库的starter  和mysql数据库依赖:

<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>cn.et</groupId>  <artifactId>SbLesson</artifactId>  <version>0.0.1-SNAPSHOT</version>  <parent>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-parent</artifactId>    <version>1.5.9.RELEASE</version></parent><dependencies><!-- springboot每一个框架的集成都是一个starterspring-boot-starter-web加载javaee  内嵌tomcat -->    <dependency>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-web</artifactId>    </dependency>   <dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-data-jpa</artifactId></dependency><dependency>    <groupId>mysql</groupId>    <artifactId>mysql-connector-java</artifactId></dependency></dependencies></project>

添加数据库的四大要素:

spring.datasource.url=jdbc:mysql://localhost/myfoodspring.datasource.username=rootspring.datasource.password=123456spring.datasource.driver-class-name=com.mysql.jdbc.Driver

最主要的类:

package cn.et.dao;import org.springframework.data.repository.CrudRepository;import cn.et.Food;public interface FoodRepository extends CrudRepository<Food, Integer> {}

然后需要创建数据库的实体类:

package cn.et;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;@Entitypublic class Food {@Id@GeneratedValue(strategy=GenerationType.AUTO)private int foodid;@Columnprivate String foodname;@Columnprivate int price;@Columnprivate String imgpath;public int getFoodid() {return foodid;}public void setFoodid(int foodid) {this.foodid = foodid;}public String getFoodname() {return foodname;}public void setFoodname(String foodname) {this.foodname = foodname;}public int getPrice() {return price;}public void setPrice(int price) {this.price = price;}public String getImgpath() {return imgpath;}public void setImgpath(String imgpath) {this.imgpath = imgpath;}}

最后就是创建项目的Controller层:

package cn.et;import java.util.HashMap;import java.util.List;import java.util.Map;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;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;import cn.et.dao.FoodRepository;@RestController@SpringBootApplicationpublic class SbController { @AutowiredJdbcTemplate jdbc;@AutowiredFoodRepository er;@RequestMapping("/hello")public Map hello(){Map map = new HashMap();map.put("id", 1);map.put("name", "zs");return map;}@RequestMapping("/food/{foodid}")public Map getFood(@PathVariable String foodid){List<Map<String, Object>> queryForList = jdbc.queryForList("select * from food where foodid="+foodid);return queryForList.get(0);}//添加@RequestMapping("/saveFood")public String saveFood(){Food food = new Food();food.setFoodname("sss");food.setImgpath("45454");food.setPrice(15);er.save(food);return "1";}//查询@RequestMapping("/queryFood")public Food queryFood(){Food food = er.findOne(39);return food;}public static void main(String[] args) { SpringApplication.run(SbController.class, args);}}

最后访问 通过访问 (http://localhost:8080/savefood)进行添加数据库的数据 如果返回值为 "1" 则添加成功  否则失败