NIFI-7410 Fix CLOB would be unreadable code in ExecuteSql or QueryDataBaseTable

[zhangchengk]

https://issues.apache.org/jira/browse/NIFI-7410

Description of PR

fixes bug NIFI-7410

when ExecuteSql or QueryDataBaseTable processor trigger below code in JdbcCommon.java ,clob would be unreadable code（with Chinese character）,because it used
InputStream is = clob.getAsciiStream(); and rec.put(i - 1, new String(buffer));

Update JdbcCommon.java when javaSqlType is CLOB or NCLOB in convertToAvroStream method, use the DataTypeUtils.toString(clob/nClob,(String) null, StandardCharsets.UTF_8)) method to get the String

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[mattyb149]

Is there a way to add a unit test for this? Maybe inserting Chinese characters into a Derby table with a CLOB column and reading the results?

[zhangchengk]

Is there a way to add a unit test for this? Maybe inserting Chinese characters into a Derby table with a CLOB column and reading the results?

Thanks for reply. I will add a unit test for this situation.

[zhangchengk]

Is there a way to add a unit test for this? Maybe inserting Chinese characters into a Derby table with a CLOB column and reading the results?

Hi @mattyb149 I have added one unit test.Clould you help me to check the PR of the NIFI-7403 - PutSQL's transactions support #4239 if you have time? Thanks.

[pvillard31]

Hey @mattyb149 - does it look good to you?

[pvillard31]

Manually fixed the checkstyle violations and added the license to make the RAT check happy. Merging to main. Thanks @KuKuDeCheng (next time, please make sure to add the header and check the build with -Pcontrib-check)