ClassArrayClassSlotIterator.hpp

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

#if !defined(CLASSARRAYCLASSSLOTITERATOR_HPP_)
#define CLASSARRAYCLASSSLOTITERATOR_HPP_

#include "j9.h"
#include "j9cfg.h"
#include "j9consts.h"
#include "modron.h"

/** 
 * Iterate over all references in a J9ArrayClass.
 * @ingroup GC_Structs
 */
class GC_ClassArrayClassSlotIterator
{
	J9Class *_iterateClazz;
	bool _isArrayClass;
	int _state;
	
	enum {
		classArrayClassSlotIterator_state_arrayClass = 0,
		classArrayClassSlotIterator_state_componentType,
		classArrayClassSlotIterator_state_leafComponentType,
		classArrayClassSlotIterator_state_done
	};

public:
	GC_ClassArrayClassSlotIterator(J9Class *clazz) :
		_iterateClazz(clazz),
		_isArrayClass((clazz->romClass->modifiers & J9AccClassArray) != 0),
		_state(classArrayClassSlotIterator_state_arrayClass)
	{};

	J9Class *nextSlot();
	
	/**
	 * Gets the current slot's "index".
	 * @return 0 when the last call of nextSlot returned the array class.
	 * @return 1 when the last call of nextSlot returned the component type.
	 * @return 2 when the last call of nextSlot returned the leaf component type.
	 * @return -1 if nextSlot has yet to be called.
	 */
	MMINLINE IDATA getIndex() {
		/* just use the state as none of the states return multiple objects */
		return _state - 1;
	}
};

#endif /* CLASSARRAYCLASSSLOTITERATOR_HPP_ */