fixed issue with null in legacy driver's json response deserializer + test

[debychkov]

Hi, it seems, that I missed one corner case in #862

If there is NaN in response it is written as null in json "data", and my deserializer didn't check that.

This time I ran my fix through our internal tests (with wide selection of prod-like queries), and it seems that now response is deserialized like it used to before.

Example with NaN:

        String connectionUrl = "jdbc:clickhouse://localhost:8123/default";
        ClickHouseConnection clickHouseConnection = (ClickHouseConnection) DataSourceUtils.getConnection(
                new ClickHouseDataSource(connectionUrl, new ClickHouseProperties()));
        ClickHouseResponse clickHouseResponse = clickHouseConnection.createStatement().executeQueryClickhouseResponse("SELECT 0/0 AS n");

It failed with exception:

Exception in thread "main" java.lang.IllegalArgumentException: unexpected jsonElementType: null
	at ru.yandex.clickhouse.response.ClickHouseResponseGsonDeserializer.getAsString(ClickHouseResponseGsonDeserializer.java:82)
	at ru.yandex.clickhouse.response.ClickHouseResponseGsonDeserializer.lambda$getAsStringArray$2(ClickHouseResponseGsonDeserializer.java:69)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at ru.yandex.clickhouse.response.ClickHouseResponseGsonDeserializer.getAsStringArray(ClickHouseResponseGsonDeserializer.java:68)
	at ru.yandex.clickhouse.response.ClickHouseResponseGsonDeserializer.lambda$deserialize$1(ClickHouseResponseGsonDeserializer.java:32)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at ru.yandex.clickhouse.response.ClickHouseResponseGsonDeserializer.deserialize(ClickHouseResponseGsonDeserializer.java:31)
	at ru.yandex.clickhouse.response.ClickHouseResponseGsonDeserializer.deserialize(ClickHouseResponseGsonDeserializer.java:14)
	at com.google.gson.internal.bind.TreeTypeAdapter.read(TreeTypeAdapter.java:69)

[debychkov]

One failed test, but I don't think it is related to my pr

Error:  Tests run: 251, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 18.907 s <<< FAILURE! - in TestSuite
Error:  com.clickhouse.jdbc.ClickHousePreparedStatementTest.testInsertWithFunction  Time elapsed: 0.021 s  <<< FAILURE!
java.sql.BatchUpdateException: 
Code: 441. DB::Exception: Invalid IPv6 value: while executing 'FUNCTION if(isNull(IPv4ToIPv6(toIPv4(_dummy_0))) : 3, defaultValueOfTypeName('IPv6') :: 2, _CAST(IPv4ToIPv6(toIPv4(_dummy_0)), 'IPv6') :: 5) -> if(isNull(IPv4ToIPv6(toIPv4(_dummy_0))), defaultValueOfTypeName('IPv6'), _CAST(IPv4ToIPv6(toIPv4(_dummy_0)), 'IPv6')) IPv6 : 1': While executing ValuesBlockInputFormat. (CANNOT_PARSE_DOMAIN_VALUE_FROM_STRING) (version 22.3.2.1)
, server ClickHouseNode(addr=http:localhost:49176, db=test_preparedstatement)@-1017961213
	at com.clickhouse.jdbc.ClickHousePreparedStatementTest.testInsertWithFunction(ClickHousePreparedStatementTest.java:920)

[zhicwu]

Thank you @debychkov! I'll merge the pull request after some more testing(null value, NaN and ±Inf etc.).

As to the build failure, it's irrelevant since it's a server side issue. I filed ClickHouse/ClickHouse#35449 hoping it will be fixed soon.