Druid连接池的简单使用

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql:///ManageSys
username=root
password=admin123
initialSize=5
maxActive=10
maxWait=3000
maxIdle=6
minIdle=3

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

import javax.sql.DataSource;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class JdbcUtil {

    //    创建数据源对象
    private static DataSource dataSource;

    static {

//        新建一个配置文件对象
        Properties properties = new Properties();

//        通过类加载器找到文件路径，读配置文件
        InputStream inputStream = JdbcUtil.class.getResourceAsStream("/d.properties");

//        加载属性文件
        try {
            properties.load(inputStream);

//            创建连接池对象
            dataSource = DruidDataSourceFactory.createDataSource(properties);


        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }


    }


    /*
    * 从连接池中获取连接
    * */
    public static Connection getConnect(){
        Connection con = null;

        try {
            con = dataSource.getConnection();
        } catch (SQLException e) {
            e.printStackTrace();
        }

        return con;
    }



    /*
    * 关闭资源
    * */
    public static void close(Connection connection, Statement statement, ResultSet resultSet){

        if(connection!=null){
            try {
                connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if(statement!=null){
            try {
                statement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if(resultSet!=null){
            try {
                resultSet.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }



    }




}

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;

public class Main {

    public static void main(String[] args) {

        Connection connection = JdbcUtil.getConnect();

        try {
            DatabaseMetaData databaseMetaData = connection.getMetaData();
            System.out.println(databaseMetaData.getURL() + ","
                    + databaseMetaData.getUserName() + ","
                    + databaseMetaData.getDriverName());
        } catch (SQLException e) {
            e.printStackTrace();
        }


    }
}