SpringBoot（8）——JDBC 连接mysql 数据库

1.springBoot 连接mysql概述

• 配置 application.properties
• 配置 maven 依赖
• 创建数据表，代码测试

2. 配置application.properties

#datasources config
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.max-idle=10
spring.datasource.max-wait=10000
spring.datasource.min-idle=5
spring.datasource.initial-size=5
spring.datasource.validation-query=SELECT 1
spring.datasource.test-on-borrow=false
spring.datasource.test-while-idle=true
spring.datasource.time-between-eviction-runs-millis=18800
spring.datasource.jdbc-interceptors=ConnectionState;SlowQueryReport(threshold=0)

3.配置maven依赖

    <!-- MYSQL -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
    </dependency>
    <!-- Spring Boot JDBC -->
    <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-jdbc</artifactId>
    </dependency>

    <!--spring tran  -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>4.3.14.RELEASE</version>
    </dependency>

4.代码如下

• 实体类

package com.example.demo.entity;

import java.io.Serializable;
public class User implements Serializable{

    /**
     * 
     */
    private static final long serialVersionUID = -1369148652554782331L;

    private int id;
    private String name;
    private int age;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
}

• dao 层

package com.example.demo.dao;


import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import javax.annotation.Resource;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Repository;

import com.example.demo.entity.User;

@Repository
public class UserDao {

    @Resource
    private JdbcTemplate jdbcTemplate;

    public List<User> getUserList(){

        String sql = "select * from user";
        return jdbcTemplate.query(sql, new RowMapper<User>() {

            @Override
            public User mapRow(ResultSet rs, int rowNum) throws SQLException {

                User user = new User();
                user.setAge(rs.getInt("age"));
                user.setId(rs.getInt("id"));
                user.setName(rs.getString("name"));
                return user;
            }

        });

    }
}

• service 层

package com.example.demo.service;

import java.util.List;

import javax.annotation.Resource;

import org.springframework.stereotype.Service;

import com.example.demo.dao.UserDao;
import com.example.demo.entity.User;

@Service
public class UserService {

    @Resource
    private UserDao userDao;

    public List<User> getUserList(){

        return userDao.getUserList();
    }

}

• contoller 层

package com.example.demo.controller;

import java.util.List;

import javax.annotation.Resource;

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

import com.example.demo.entity.User;
import com.example.demo.service.UserService;

@RestController
public class UserController {
    @Resource 
    private UserService userService;

    @RequestMapping(value = "/user")
    public Object index() {

        List<User> list = userService.getUserList();

        return list;

    }

}

5.表结构

6.结果

完！