抄写

package tools;

import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;

public class DbHelper {
    // 配置数据的容器
    public static final Properties PROPERTIES = new Properties();

    // 加载驱动
    static {
        // 获得配置流数据
        InputStream is = DbHelper.class.getResourceAsStream("config.properties");

        // 容器读取流数据
        try {
            PROPERTIES.load(is);
        } catch (IOException e) {
            e.printStackTrace();
        }

        // 加载驱动
        try {
            Class.forName(PROPERTIES.getProperty("driver"));
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    // 获取连接
    public static Connection getConnection() {
        // 读取配置中的数据
        String url = PROPERTIES.getProperty("url");
        String user = PROPERTIES.getProperty("user");
        String pwd = PROPERTIES.getProperty("pwd");

        // 获得连接对象
        Connection connection = null;
        try {
            connection = DriverManager.getConnection(url, user, pwd);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }

        // 返回连接对象
        return connection;
    }

    // 释放资源
    public static void closeAll(Connection connection, Statement statement, ResultSet resultSet) {
        if(resultSet!=null){
            try {
                resultSet.close();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }

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

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

}