mqtt/src/main/java/com/xydl/util/DataSourceUtils.java

package com.xydl.util;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.sql.DataSource;
import java.sql.*;
import java.util.Properties;

public class DataSourceUtils {
    private static final Logger logger = LoggerFactory.getLogger(DataSourceUtils.class);
    private static DataSource dataSource;
    private static String url;

    static {
        initDataSource();
    }

    private static void initDataSource() {
        Properties properties = new Properties();
        properties.setProperty("driverClassName", "com.mysql.cj.jdbc.Driver");
        properties.setProperty("url", "jdbc:mysql://localhost:3306/cac");
        properties.setProperty("username", "root");
        properties.setProperty("password", "root");

        try {
            dataSource = DruidDataSourceFactory.createDataSource(properties);
            url = ((DruidDataSource) dataSource).getUrl();
        } catch (Exception e) {
            logger.error("init dataSource exception:", e);
        }
        logger.info("Data source has been initialized successfully!");
    }

    // 提供获取连接的方法
    public static Connection getConnection() throws SQLException {
        return dataSource.getConnection();
    }


    // 提供关闭资源的方法【connection是归还到连接池】
    // 提供关闭资源的方法 【方法重载】3 dql
    public static void closeResource(ResultSet resultSet, Statement statement, Connection connection) {
        // 关闭结果集
        closeResultSet(resultSet);
        // 关闭语句执行者
        closeStatement(statement);
        // 关闭连接
        closeConnection(connection);
    }

    // 提供关闭资源的方法 【方法重载】 2 dml
    public static void closeResource(Statement statement, Connection connection) {
        // 关闭语句执行者
        closeStatement(statement);
        // 关闭连接
        closeConnection(connection);
    }

    private static void closeConnection(Connection connection) {
        if (connection != null) {
            try {
                connection.close();
            } catch (SQLException e) {
                logger.error("closeConnection exception", e);
            }
        }
    }

    private static void closeStatement(Statement statement) {
        if (statement != null) {
            try {
                statement.close();
            } catch (SQLException e) {
                logger.error("closeStatement exception", e);
            }
        }
    }

    private static void closeResultSet(ResultSet resultSet) {
        if (resultSet != null) {
            try {
                resultSet.close();
            } catch (SQLException e) {
                logger.error("closeResultSet exception", e);
            }
        }
    }
}