java hivejdbc 工具类

以下是一个Java HiveJDBC工具类的示例，它使用了上述提到的db.properties文件中的配置信息：

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

public class HiveJdbcUtil {

    private static String driverClass;
    private static String userName;
    private static String password;
    private static String url;

    static {
        try {
            // 加载db.properties配置文件
            InputStream in = HiveJdbcUtil.class.getClassLoader().getResourceAsStream("db.properties");
            Properties props = new Properties();
            props.load(in);

            // 读取配置信息
            driverClass = props.getProperty("driver_class");
            userName = props.getProperty("user_name");
            password = props.getProperty("password");
            url = props.getProperty("url");

            // 加载Hive JDBC驱动
            Class.forName(driverClass);
        } catch (IOException | ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    /**
     * 获取Hive连接
     * @return Connection
     */
    public static Connection getConnection() {
        Connection conn = null;
        try {
            conn = DriverManager.getConnection(url, userName, password);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return conn;
    }

    /**
     * 关闭Hive连接
     * @param conn Connection
     * @param stmt Statement
     * @param rs ResultSet
     */
    public static void closeConnection(Connection conn, Statement stmt, ResultSet rs) {
        try {
            if (rs != null) {
                rs.close();
            }
            if (stmt != null) {
                stmt.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    /**
     * 执行Hive SQL查询
     * @param sql String
     * @return ResultSet
     */
    public static ResultSet executeQuery(String sql) {
        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            stmt = conn.createStatement();
            rs = stmt.executeQuery(sql);
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            closeConnection(conn, stmt, null);
        }
        return rs;
    }
}