ClassSuperclassesIterator.hpp

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

#if !defined(CLASSSUPERCLASSESITERATOR_HPP_)
#define CLASSSUPERCLASSESITERATOR_HPP_

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

/**
 * Iterate over the superclasses references of a class
 * @ingroup GC_Structs
 */
class GC_ClassSuperclassesIterator
{
	UDATA _classDepth;
	IDATA _index;
	J9Class **_superclassPtr;

public:
	GC_ClassSuperclassesIterator(J9Class *clazz) :
		_classDepth(J9CLASS_DEPTH(clazz)),
		_index(-1),
		_superclassPtr(clazz->superclasses)
	{};

	J9Class *nextSlot();
	
	/**
	 * Gets the current superclass index.
	 * The high index is at the end of the superclass chain, with 0 being the direct superclass.
	 * @return index of the last superclass returned by nextSlot.
	 * @return -1 if nextSlot has yet to be called.
	 */
	MMINLINE IDATA getIndex() {
		return _index;
	}

};

#endif /* CLASSSUPERCLASSESITERATOR_HPP_ */