连接池

package com.wang.druid;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.sql.Connection;
import java.util.Collections;
import java.util.Properties;

public class druidjdbc {
    public static void main(String[] args) throws Exception {
        Properties properties=new Properties();
        properties.load(new FileInputStream("src/Druid.properties"));
        DataSource dataSource = DruidDataSourceFactory.createDataSource(properties);
        Connection connection=dataSource.getConnection();
        System.out.println(connection);
    }
}

首先手写Druid配置文件，一定要先加Druid的jar包

<dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.2.8</version>
    </dependency>

配置文件

driverClassName=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/jdbc?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&useSSL=false&allowPublicKeyRetrieval=true
username=root
password=wjs790929
initialSize=5
maxActive=10
maxWait=3000

新建Properties对象，调用load方法来加载配置（路径要写好）
创建连接池导入配置
最后创建连接
之后步骤和之前一样