springboot连接jdbc

1.导包

		<!-- ==链接数据库 start== -->
		<!--jdbc-->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<!--mysql-->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>5.1.21</version>
		</dependency>
		<!-- ==链接数据库 end== -->

2.配置文件配置

### jdbc mysql
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/db
spring.datasource.username=root
spring.datasource.password=123
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

3.增删改查

package com.syf.study.service;
import com.syf.study.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
@Service
public class UserService {
    @Autowired
    private JdbcTemplate jdbcTemplate;

    public int add(User user){                                    //因为ID是自增，所以可以写null
        int count = jdbcTemplate.update("insert into `user` (id,username,password) values(null,?,?)", user.getUsername(), user.getPassword());

        return count;
    }

    public int delete(User user){
        int count = jdbcTemplate.update("delete `user` WHERE id=?", user.getId());

        return count;
    }

    public int update(User user){
        int count = jdbcTemplate.update("UPDATE  `user` SET username=?,password=? WHERE ID=?", user.getUsername(), user.getPassword(),user.getId());

        return count;
    }
    public List<User> queryAll(){
        List<User> list = jdbcTemplate.query("select * from user", new BeanPropertyRowMapper(User.class));
        for (User u: list
             ) {
            System.out.println("---"+u.toString());
        }
        return list;
    }

    public List<User> queryByPropertice(User user){
        List<User> query = jdbcTemplate.query("select * from user WHERE username=? and password=?", new Object[]{user.getUsername(), user.getPassword()}, new BeanPropertyRowMapper(User.class));
        for (User u: query
                ) {
            System.out.println("==="+u.toString());
        }
        return query;
    }

}