本系列教程使用idea完成
idea安装springboot插件
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需求：
jdk1.8及以上
maven3.2+
第一步
新建项目，输入项目名gs-accessing-data-mysql
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第二步
勾选Spring Web, Spring Data JPA, and MySQL Driver 点击完成
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第三步
创建数据库
mysql> create database db_example; --创建数据库
mysql> create user 'springuser'@'%' identified by 'ThePassword'; -- 创建用户
mysql> grant all on db_example.* to 'springuser'@'%'; -- 给数据库授权
第四步
在如下文件加入数据库连接配置
src/main/resources/application.properties
spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://${MYSQL_HOST:localhost}:3306/db_example
spring.datasource.username=springuser
spring.datasource.password=ThePassword
第五步
创建实体类 User.java文件
src/main/java/com/example/accessingdatamysql/User.java
package com.example.accessingdatamysql;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity // This tells Hibernate to make a table out of this class
public class User {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;
private String name;
private String email;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
}
第六步
创建数据创库UserRepository
package com.example.accessingdatamysql;
import org.springframework.data.repository.CrudRepository;
import com.example.accessingdatamysql.User;
// This will be AUTO IMPLEMENTED by Spring into a Bean called userRepository
// CRUD refers Create, Read, Update, Delete
public interface UserRepository extends CrudRepository<User, Integer> {
}
第七步
创建控制器
src/main/java/com/example/accessingdatamysql/MainController.java
package com.example.accessingdatamysql;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
@Controller // This means that this class is a Controller
@RequestMapping(path="/demo") // This means URL's start with /demo (after Application path)
public class MainController {
@Autowired // This means to get the bean called userRepository
// Which is auto-generated by Spring, we will use it to handle the data
private UserRepository userRepository;
@PostMapping(path="/add") // Map ONLY POST Requests
public @ResponseBody String addNewUser (@RequestParam String name
, @RequestParam String email) {
// @ResponseBody means the returned String is the response, not a view name
// @RequestParam means it is a parameter from the GET or POST request
User n = new User();
n.setName(name);
n.setEmail(email);
userRepository.save(n);
return "Saved";
}
@GetMapping(path="/all")
public @ResponseBody Iterable<User> getAllUsers() {
// This returns a JSON or XML with the users
return userRepository.findAll();
}
}
第八步
使用post访问localhost:8080/demo/add
$ curl localhost:8080/demo/add -d name=First -d email=someemail@someemailprovider.com
或者使用postman模拟post访问
程序返回Saved
使用浏览器访问localhost:8080/demo/all 或者使用
$ curl 'localhost:8080/demo/all'
返回
[{"id":1,"name":"First","email":"someemail@someemailprovider.com"}]
