数据源工具类

public class JdbcUtils {

    private static String driverName = "com.mysql.cj.jdbc.Driver";

    private static String url = "jdbc:mysql://10.2.3.21:9090/stdb?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf-8";

    private static String username = "stdb";

    private static String password = "123456";


    public static Connection getConnection() throws ClassNotFoundException, SQLException {
//1. 注册数据库的驱动
        Class.forName(driverName);
        return DriverManager.getConnection(url, username, password);
    }

    //释放rs
    public static void release(ResultSet rs) {
        //释放rs
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            rs = null;
        }
    }

    //释放statement
    public static void release(Statement statement) {
//释放statement
        if (statement != null) {
            try {
                statement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            statement = null;
        }
    }

    //释放connection
    public static void release(Connection connection) {
        //释放connection
        if (connection != null) {
            try {
                connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            connection = null;
        }
    }

    //释放statement 和connection
    public static void release(Statement statement, Connection connection) {
        release(statement);
        release(connection);
    }

    public static List<Map<String, Object>> getDataAll(String sql) {
        List<Map<String, Object>> result = new ArrayList<>();
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;
        try {
            connection = getConnection();
            statement = connection.createStatement();
            resultSet = statement.executeQuery(sql);
            ResultSetMetaData rsmd = resultSet.getMetaData();
            int size = rsmd.getColumnCount();
            while (resultSet.next()) {
                Map<String, Object> map = new HashMap<>();
                for (int i = 0; i < size; i++) {
                    map.put(rsmd.getColumnName(i + 1), resultSet.getString(i + 1));
                }
                result.add(map);
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } finally {
            try {
                if (resultSet != null) {
                    resultSet.close();
                }
                if (statement != null) {
                    statement.close();
                }
                if (connection != null) {
                    connection.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return result;
    }

}

调用

String format = new SimpleDateFormat("yyyy-MM-dd").format(new Date());
List<Map<String, Object>> dataAll = JdbcUtils.getDataAll("select * from sitedata where date_format(RcvTime,'%Y-%m-%d')='"+format+"' order by RcvTime");