JDBC

    /**
     * Query the sql tool class of a single class.
     * @param sql sql
     * @param args args
     * @return class
     */
    public Tab getQuerySql(String sql, Object... args) {
        try (PreparedStatement ps = connection.prepareStatement(sql)) {
            for (int i = 0; i < args.length; i++) {
                ps.setObject(i + 1, args[i]);
            }
            // Get ResultSet
            ResultSet resultSet = ps.executeQuery();
            // Get the metadata of the result set
            ResultSetMetaData metaData = resultSet.getMetaData();
            // Get the number of columns
            int columnCount = metaData.getColumnCount();
            if (resultSet.next()) {
                Tab tab = new Tab();
                for (int i = 0; i < columnCount; i++) {
                    // Get the column value of each column: through ResultSet
                    Object columnValue = resultSet.getObject(i + 1);
                    // Get the alias of the column through ResultSetMetaData
                    String columnLabel = metaData.getColumnLabel(i + 1);
                    // Through reflection, assign the specified name of the object columnLabel to the specified columnValue
                    Field field = Tab.class.getDeclaredField(columnLabel);
                    field.setAccessible(true);
                    field.set(tab, columnValue);
                }
                return tab;
            }
        } catch (Exception throwables) {
            throwables.printStackTrace();
        }
        return null;
    }

    /**
     * Add, delete, modify and check a single class.
     * @param sql sql 
     * @param args args
     * @return boolean
     */
    public boolean executeSql(String sql, Object... args) {
        try (PreparedStatement ps = connection.prepareStatement(sql)) {
            for (int i = 0; i < args.length; i++) {
                ps.setObject(i + 1, args[i]);
            }
            return ps.execute();
        } catch (Exception throwables) {
            throwables.printStackTrace();
        }
        return false;
    }