ConstantPoolClassSlotIterator.hpp

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/**
 * @file
 * @ingroup GC_Structs
 */

#if !defined(CONSTANTPOOLCLASSSLOTITERATOR_HPP_)
#define CONSTANTPOOLCLASSSLOTITERATOR_HPP_

#include "j9.h"
#include "j9cfg.h"
#include "j9cp.h"
#include "modron.h"

/**
 * Iterate over class references (but not object references) in the constant pool of a class.
 * 
 * @see GC_ConstantPoolObjectSlotIterator
 * @ingroup GC_Structs
 */
class GC_ConstantPoolClassSlotIterator
{

	J9Object **_cpEntry;
	U_32 _cpEntryCount;
	U_32 _cpEntryTotal;
	U_32 *_cpDescriptionSlots;
	U_32 _cpDescription;
	UDATA _cpDescriptionIndex;
	
public:
	GC_ConstantPoolClassSlotIterator(J9Class *clazz) :
		_cpEntry((J9Object **)J9_CP_FROM_CLASS(clazz)),
		_cpEntryCount(clazz->romClass->ramConstantPoolCount)
	{
		_cpEntryTotal = _cpEntryCount;
		if(_cpEntryCount) {
			_cpDescriptionSlots = SRP_PTR_GET(&clazz->romClass->cpShapeDescription, U_32 *);
			_cpDescriptionIndex = 0;
		}

	};

	/**
	 * Gets the current constant pool index.
	 * @return zero based constant pool index of the entry returned by the last call of nextSlot.
	 * @return -1 if nextSlot has yet to be called.
	 */
	MMINLINE IDATA getIndex() {
		return _cpEntryTotal - _cpEntryCount - 1;
	}

	J9Class *nextSlot();
};

#endif /* CONSTANTPOOLCLASSSLOTITERATOR_HPP_ */