Co-authored-by: NTernence <lujingshang@126.com>

* #4482 Correct the `DataTypeName` for oracle

* delete blank line

* delete invalid assertion

* recover

* Instead of SimpleTableSegment, TableSegment should be the member of SelectStatement

* format todo block

* format fixme block

* fix #4565 for distinct bug

* Polish package import

* Polish for checkstyle

* Polish checkstyle for test

* fix unit test

* add testcases for distinct without order by

* remove an unused import

* Polish for checkstyle

* Polish the checkstyle

* add sql parser cases

* Polish checkstyle

* Move XXXAvailable to type package

* refactor optional for java8

* simplify diamond syntax

* refactor lambda for java8

* remove guava optional

* fix typo

* adjust package structure of AbstractSQLStatement

* Link RL statement and visitor

* create SubqueryExpressionSegment

* make it final

* modify sub query assertion

* add alias for subquery grammar

* move subquery segment

* upgrade java version from 7 to 8

* upgrade lambda expr for java8

* use java8 Optional instead of guava Optional

* use java8 Optional instead of guava Optional

* #4482 Correct the `DataTypeName` for SQLServer

* format

* add a empty line at end of file.

* Create tableNameSegment

* check style

* #4482 Correct the `DataTypeName` for PostgreSQL

* remove doublePrecision and add keyword DOUBLEPRECISION in PostgreSQLKeyword.g4

* refactor TableSegmentsAvailable.getAllTables()

* remove TableSegmentAvailable

* decouple getAllTables and getTables

* refactor AlterTableStatementTestCase

* refactor CreateTableStatementTestCase

* add AlterTableStatement.addedConstraintDefinitions

* adjust rule seq for mysql ddl

* refactor AlterTableStatement.addedColumnDefinitions' type from ColumnDefinitionSegment to AddColumnDefinitionSegment

* refactor AddColumnDefinitionSegment.columnDefinition to columnDefinitions

* add AlterDefinitionSegment

* add AlterTableStatement.addConstraintDefinitions

* refactor alter table for add constraint of MySQLDDLVisitor

* refactor alter table for add constraint of MySQLDDLVisitor

* refactor alter table for modify column of MySQLDDLVisitor

* refactor alter table for drop column of MySQLDDLVisitor

* refactor alter table of Oracle

* refactor alter table of SQLServer

* refactor alter table of PostgreSQL

* refactor alter table of SQL92

* for checkstyle

* fix new test cases

* #4406 fix MySQL, PostgreSQL DDL cannot parse Integer, Double, Decimal

* #4459 Correct the `DataTypeName` for mysql

* remove createDefinitions from MySQL g4

* add CreateDefinitionSegment

* rename rule name inside columnDefinition

* parse referencedTables on ColumnDefinitionSegment

* parse ConstraintDefinitionSegment on DefinitionSegment

* refactor CreateTable with CreateDefinitionSegment for MySQL

* refactor CreateTable with CreateDefinitionSegment for PostgreSQL

* refactor CreateTable with CreateDefinitionSegment for Oracle

* refactor CreateTable with CreateDefinitionSegment for SQLServer

* refactor CreateTable with CreateDefinitionSegment for SQL92

* fix parser test cases

* Decouple TableTokenGenerator and SQLStatement.getAllSQLSegments()

* Parse variable name for SET statement

* refactor SQLParserEngine

* refactor SQLParserEngine

* refactor SQLParser

* swap SQLParserEngine and SQLParserKernel

* use SQLParseEngine instead of SQLParserEngine in TextProtocolBackendHandlerFactory

* remove SQLParserEngine

* rename SQLParseEngine to SQLParserEngine

* rename SQLParseEngineFactory to SQLParserEngineFactory

* rename SQLParserKernel to SQLParserExecutor

* rename SQLParserEntry to SQLParserConfiguration

* Filter alias's owner of join table

* fix test case

* Transfer SQL parser engine to new one

* Add new InsertStatement for multiple insert

* ignore long sql

* Support lock clause for visitor

* support insert sql without insert columns

* add fixme

* correct sql cases

* delete fixme

* delete db type judgement

* add fixme

* modify SQLParserParameterizedTest.java

* modify SQLParseEngine

* delete VisitorParameterizedParsingTest

* check style

* fix issue of sub query

* fix issue for db tests

* fix issue for encrypt insert without columns

* add fixme for sharding insert sql

* fix drop and create index for pg

* pass some test cases

* fix issue in ShadowPreparedStatementTest

* handle BooleanLiteralValue

* fix issue from SimpleJudgementEngineTest

* fix issue for proxy

* delete invalid test

* ADD visitBeginTransaction

* NOTE checkTestCases();

* keep old parser

* not run sub query tests

* make tests run well

* reverse

* check style

* check style

* delete NewInstanceServiceLoader

* decouple find LimitSegment with select statement

* refactor SelectStatement.lock