MetaDataChangedSubscriber throws an exception when alter storage unit

[RaigorJiang]

Bug Report

Which version of ShardingSphere did you use?

5.5.2-SNAPSHOT master f39b52b

Which project did you use? ShardingSphere-JDBC or ShardingSphere-Proxy?

ShardingSphere-Proxy

Expected behavior

Alter storage unit success

Actual behavior

MetaDataChangedSubscriber throws an exception

Reason analyze (If you can)

No

Steps to reproduce the behavior, such as: SQL to execute, sharding rule configuration, when exception occur etc.

1. create database

CREATE DATABASE sharding_db;
USE sharding_db;

REGISTER STORAGE UNIT ds_0 (
    URL="jdbc:mysql://127.0.0.1:3306/demo_ds_0?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
), ds_1 (
    URL="jdbc:mysql://127.0.0.1:3306/demo_ds_1?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
);

2. create sharding table rule

CREATE SHARDING TABLE RULE t_order (
STORAGE_UNITS(ds_0,ds_1),
SHARDING_COLUMN=order_id,
TYPE(NAME="MOD",PROPERTIES("sharding-count"="4")));

3. create table

DROP TABLE IF EXISTS t_order;
CREATE TABLE `t_order` (
        `id` BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
        `order_id` BIGINT(20) UNSIGNED NOT NULL COMMENT 'order id',
        PRIMARY KEY (`id`)
);

4. active version before alter

5. alter storage unit

ALTER STORAGE UNIT ds_0 (
    URL="jdbc:mysql://127.0.0.1:3306/demo_ds_0?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
), ds_1 (
    URL="jdbc:mysql://127.0.0.1:3306/demo_ds_1?serverTimezone=UTC&useSSL=false&allowPublicKeyRetrieval=true",
    USER="root",
    PASSWORD="123456",
    PROPERTIES("maximumPoolSize"=10)
);

6. active version after alter