greenplumn CParseHandlerSequence 源码

  • 2022-08-18
  • 浏览 (52)

greenplumn CParseHandlerSequence 代码

文件路径:/src/backend/gporca/libnaucrates/src/parser/CParseHandlerSequence.cpp

//---------------------------------------------------------------------------
//	Greenplum Database
//	Copyright (C) 2012 EMC Corp.
//
//	@filename:
//		CParseHandlerSequence.cpp
//
//	@doc:
//		Implementation of the SAX parse handler class for parsing sequence
//		operators
//---------------------------------------------------------------------------

#include "naucrates/dxl/parser/CParseHandlerSequence.h"

#include "naucrates/dxl/operators/CDXLOperatorFactory.h"
#include "naucrates/dxl/operators/CDXLPhysicalDynamicTableScan.h"
#include "naucrates/dxl/operators/CDXLPhysicalSequence.h"
#include "naucrates/dxl/parser/CParseHandlerFactory.h"
#include "naucrates/dxl/parser/CParseHandlerFilter.h"
#include "naucrates/dxl/parser/CParseHandlerProjList.h"
#include "naucrates/dxl/parser/CParseHandlerProperties.h"
#include "naucrates/dxl/parser/CParseHandlerTableDescr.h"
#include "naucrates/dxl/parser/CParseHandlerUtils.h"

using namespace gpdxl;


XERCES_CPP_NAMESPACE_USE

//---------------------------------------------------------------------------
//	@function:
//		CParseHandlerSequence::CParseHandlerSequence
//
//	@doc:
//		Constructor
//
//---------------------------------------------------------------------------
CParseHandlerSequence::CParseHandlerSequence(
	CMemoryPool *mp, CParseHandlerManager *parse_handler_mgr,
	CParseHandlerBase *parse_handler_root)
	: CParseHandlerPhysicalOp(mp, parse_handler_mgr, parse_handler_root),
	  m_is_inside_sequence(false)
{
}


//---------------------------------------------------------------------------
//	@function:
//		CParseHandlerSequence::StartElement
//
//	@doc:
//		Invoked by Xerces to process an opening tag
//
//---------------------------------------------------------------------------
void
CParseHandlerSequence::StartElement(const XMLCh *const element_uri,
									const XMLCh *const element_local_name,
									const XMLCh *const element_qname,
									const Attributes &attrs)
{
	if (!m_is_inside_sequence &&
		0 == XMLString::compareString(
				 CDXLTokens::XmlstrToken(EdxltokenPhysicalSequence),
				 element_local_name))
	{
		// new sequence operator
		// parse handler for the proj list
		CParseHandlerBase *proj_list_parse_handler =
			CParseHandlerFactory::GetParseHandler(
				m_mp, CDXLTokens::XmlstrToken(EdxltokenScalarProjList),
				m_parse_handler_mgr, this);
		m_parse_handler_mgr->ActivateParseHandler(proj_list_parse_handler);

		//parse handler for the properties of the operator
		CParseHandlerBase *prop_parse_handler =
			CParseHandlerFactory::GetParseHandler(
				m_mp, CDXLTokens::XmlstrToken(EdxltokenProperties),
				m_parse_handler_mgr, this);
		m_parse_handler_mgr->ActivateParseHandler(prop_parse_handler);

		// store child parse handlers in array
		this->Append(prop_parse_handler);
		this->Append(proj_list_parse_handler);
		m_is_inside_sequence = true;
	}
	else
	{
		// child of the sequence operator
		CParseHandlerBase *child_parse_handler =
			CParseHandlerFactory::GetParseHandler(m_mp, element_local_name,
												  m_parse_handler_mgr, this);
		m_parse_handler_mgr->ActivateParseHandler(child_parse_handler);
		this->Append(child_parse_handler);
		child_parse_handler->startElement(element_uri, element_local_name,
										  element_qname, attrs);
	}
}

//---------------------------------------------------------------------------
//	@function:
//		CParseHandlerSequence::EndElement
//
//	@doc:
//		Invoked by Xerces to process a closing tag
//
//---------------------------------------------------------------------------
void
CParseHandlerSequence::EndElement(const XMLCh *const,  // element_uri,
								  const XMLCh *const element_local_name,
								  const XMLCh *const  // element_qname
)
{
	if (0 != XMLString::compareString(
				 CDXLTokens::XmlstrToken(EdxltokenPhysicalSequence),
				 element_local_name))
	{
		CWStringDynamic *str = CDXLUtils::CreateDynamicStringFromXMLChArray(
			m_parse_handler_mgr->GetDXLMemoryManager(), element_local_name);
		GPOS_RAISE(gpdxl::ExmaDXL, gpdxl::ExmiDXLUnexpectedTag,
				   str->GetBuffer());
	}

	// construct node from the created child nodes
	CParseHandlerProperties *prop_parse_handler =
		dynamic_cast<CParseHandlerProperties *>((*this)[0]);

	CDXLPhysicalSequence *dxl_op = GPOS_NEW(m_mp) CDXLPhysicalSequence(m_mp);
	m_dxl_node = GPOS_NEW(m_mp) CDXLNode(m_mp, dxl_op);

	// set statistics and physical properties
	CParseHandlerUtils::SetProperties(m_dxl_node, prop_parse_handler);

	// add project list
	CParseHandlerProjList *proj_list_parse_handler =
		dynamic_cast<CParseHandlerProjList *>((*this)[1]);
	GPOS_ASSERT(nullptr != proj_list_parse_handler);
	AddChildFromParseHandler(proj_list_parse_handler);

	const ULONG size = this->Length();
	// add constructed children from child parse handlers
	for (ULONG idx = 2; idx < size; idx++)
	{
		CParseHandlerPhysicalOp *child_parse_handler =
			dynamic_cast<CParseHandlerPhysicalOp *>((*this)[idx]);
		GPOS_ASSERT(nullptr != child_parse_handler);
		AddChildFromParseHandler(child_parse_handler);
	}

#ifdef GPOS_DEBUG
	dxl_op->AssertValid(m_dxl_node, false /* validate_children */);
#endif	// GPOS_DEBUG

	// deactivate handler
	m_parse_handler_mgr->DeactivateHandler();
}

// EOF

相关信息

greenplumn 源码目录

相关文章

greenplumn CParseHandlerAgg 源码

greenplumn CParseHandlerAppend 源码

greenplumn CParseHandlerArray 源码

greenplumn CParseHandlerAssert 源码

greenplumn CParseHandlerBase 源码

greenplumn CParseHandlerBroadcastMotion 源码

greenplumn CParseHandlerCTEConfig 源码

greenplumn CParseHandlerCTEList 源码

greenplumn CParseHandlerColDescr 源码

greenplumn CParseHandlerColStats 源码

0  赞