* Add exception for unsupported SQL, incomplete rules and other exceptions.

* check style

Rename SQLExecuteEngine.generateExecutionContext and JDBCExecutorWrapper.generateExecutionContext (#7057)

* Decouple AuthenticationEngine and BackendConnection

* Decouple AuthenticationEngine and BackendConnection

* Refactor PreparedStatementExecutorWrapper

* Rename JDBCExecutorWrapper.generateExecutionContext

* Rename SQLExecuteEngine.generateExecutionContext

* Decouple AuthenticationEngine and BackendConnection

* Decouple AuthenticationEngine and BackendConnection

* revise java doc

* Add generic type for JDBCDatabaseCommunicationEngine

* Add generic type for ExecutionContext

* Add generic type for JDBCExecuteEngine

* Refactor JDBCExecutorWrapper

* Refactor JDBCExecutorWrapper

* Refactor StatementExecutorWrapper

* For code format

* Add sharding rule assertion

* Add encrypt rule assertion

* Add master-slave rule assertion
Add shadow rule assertion

* add test case for pg codesc and constants

* fix check style error check

* fix mockito strict check

* remove un finish test case

* add pg test case statement registry and column desc packet

* remove blank line

* ShardingProxy support checking table exists for createTable SQL

* check style

Add test case of pg binary value

* fix subquery sharding key check result

* fix checkstyle and test case

* Decouple AuthenticationEngine and BackendConnection

* Decouple AuthenticationEngine and BackendConnection

* Refactor BackendResponse judge sequence of MySQLComQueryPacketExecutor

* Refactor BackendResponse judge sequence of MySQLComStmtExecuteExecutor

* Refactor BackendResponse judge sequence of PostgreSQLComBindExecutor

* Refactor BackendResponse judge sequence of PostgreSQLComQueryExecutor

* Refactor MySQLComQueryPacketExecutor

* Refactor MySQLComStmtExecuteExecutor

* Refactor PostgreSQLComBindExecutor

* Refactor PostgreSQLComQueryExecutor

* Decouple AuthenticationEngine and BackendConnection

* Decouple AuthenticationEngine and BackendConnection

* Unify userName to username

* Refactor CommandExecutorTask

* Refactor MySQLComQueryPacketExecutor.isQueryResponse

* Refactor MySQLComStmtExecuteExecutor.isQueryResponse

* Refactor PostgreSQLComBindExecutor.isQueryResponse

* Refactor PostgreSQLComQueryExecutor.isQueryResponse

* add test cases

* add test cases

* add test cases

* add test case for pg codesc and constants

* fix check style error check

* fix mockito strict check

* remove un finish test case

* test pg binary packet protocol

* add test case for pg codesc and constants

* fix check style error check

* fix mockito strict check

* remove un finish test case

* add pg packet factory test case

* add test case for pg codesc and constants

* fix check style error check

* fix mockito strict check

* remove un finish test case

* Decouple AuthenticationEngine and BackendConnection

* Decouple AuthenticationEngine and BackendConnection

* Refactor MySQLAuthenticationEngine

* Refactor CommandExecutorTask

* Refactor MySQLAuthenticationEngine

* Add AuthenticationResult to refactor AuthenticationEngine

#7014, keep origin

Fixes heartbeat unit test errors

* rename return variable to "result"

* remove useless linefeed

Co-authored-by: qiulu3 <Lucas209910>