Debezium will throws this exception：

Reporting error:
org.apache.kafka.connect.errors.ConnectException: Streaming result set com.mysql.cj.protocol.a.result.ResultsetRowsStreaming@37181575 is still active. No statements may be issued when any streaming result sets are open and in use on a given connection. Ensure that you have called .close() on any active streaming result sets before attempting more queries. Error code: 0; SQLSTATE: S1000.
at io.debezium.connector.mysql.AbstractReader.wrap(AbstractReader.java:241)
at io.debezium.connector.mysql.AbstractReader.failed(AbstractReader.java:218)
at io.debezium.connector.mysql.SnapshotReader.execute(SnapshotReader.java:857)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.sql.SQLException: Streaming result set com.mysql.cj.protocol.a.result.ResultsetRowsStreaming@37181575 is still active. No statements may be issued when any streaming result sets are open and in use on a given connection. Ensure that you have called .close() on any active streaming result sets before attempting more queries.
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129)
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
at com.mysql.cj.jdbc.ConnectionImpl.commit(ConnectionImpl.java:814)
at io.debezium.connector.mysql.SnapshotReader.execute(SnapshotReader.java:773)
... 3 common frames omitted

But in fact, this anomaly is not the root cause. It is because there is no catch sql exception in the following locations:

This is actually similar to a code like this:

In the end, only one irrelevant exception was printed, and the most critical exception was ignored. (In my code, illegalargument exception is the root cause, but it actually prints nullpointerexception)