protected String changeTable(String sql) {

        ExceptionUtils.throwMpe(null == tableNameHandler, "Please implement TableNameHandler processing logic");

        TableNameParser parser = new TableNameParser(sql);//解析出所有语句

        List<TableNameParser.SqlToken> names = new ArrayList<>();

        parser.accept(names::add);根据指定关键词获取表名

        StringBuilder builder = new StringBuilder();

        int last = 0;

        for (TableNameParser.SqlToken name : names) {

            int start = name.getStart();

            if (start != last) {

                builder.append(sql, last, start);

                builder.append(tableNameHandler.dynamicTableName(sql, name.getValue()));

            }

            last = name.getEnd();

        }

        if (last != sql.length()) {

            builder.append(sql.substring(last));

        }

        if (hook != null) {

            hook.run();

        }

        return builder.toString();

    }