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QIntCacheIterator Class

发布于 2019-10-04 15:00:51 字数 6009 浏览 1129 评论 0 收藏 0

The QIntCacheIterator class provides an iterator for QIntCache collections. More...

#include <qintcache.h>

List of all member functions.

Public Members

  • QIntCacheIterator ( constQIntCache<type>&cache )
  • QIntCacheIterator ( constQIntCacheIterator<type>&ci )
  • QIntCacheIterator<type> & operator= ( constQIntCacheIterator<type>&ci )
  • uint count () const
  • bool isEmpty () const
  • bool atFirst () const
  • bool atLast () const
  • type * toFirst ()
  • type * toLast ()
  • operator type * () const
  • type * current () const
  • long currentKey () const
  • type * operator() ()
  • type * operator++ ()
  • type * operator+= ( uintjump )
  • type * operator-- ()
  • type * operator-= ( uintjump )

Detailed Description

The QIntCacheIterator class provides an iterator for QIntCache collections.

Note that the traversal order is arbitrary; you are not guaranteed any particular order. If new objects are inserted into the cache while the iterator is active, the iterator may or may not see them.

Multiple iterators are completely independent, even when they operate on the same QIntCache. QIntCache updates all iterators that refer an item when that item is removed.

QIntCacheIterator provides an operator++(), and an operator+=() to traverse the cache; current() and currentKey() to access the current cache item and its key; atFirst() atLast(), which return TRUE if the iterator points to the first/last item in the cache; isEmpty(), which returns TRUE if the cache is empty; and count(), which returns the number of items in the cache.

Note that atFirst() and atLast() refer to the iterator's arbitrary ordering, not to the cache's internal LRU list.

See also QIntCache, Collection Classes and Non-GUI Classes.


Member Function Documentation

QIntCacheIterator::QIntCacheIterator ( constQIntCache<type>&cache )

Constructs an iterator for cache. The current iterator item is set to point to the first item in the cache (or rather, the first item is defined to be the item at which this constructor sets the iterator to point).

QIntCacheIterator::QIntCacheIterator ( constQIntCacheIterator<type>&ci )

Constructs an iterator for the same cache as ci. The new iterator starts at the same item as ci.current(), but moves independently from there on.

bool QIntCacheIterator::atFirst () const

Returns TRUE if the iterator points to the first item in the cache; otherwise returns FALSE. Note that this refers to the iterator's arbitrary ordering, not to the cache's internal LRU list.

See also toFirst() and atLast().

bool QIntCacheIterator::atLast () const

Returns TRUE if the iterator points to the last item in the cache; otherwise returns FALSE. Note that this refers to the iterator's arbitrary ordering, not to the cache's internal LRU list.

See also toLast() and atFirst().

uint QIntCacheIterator::count () const

Returns the number of items in the cache on which this iterator operates.

See also isEmpty().

type * QIntCacheIterator::current () const

Returns a pointer to the current iterator item.

long QIntCacheIterator::currentKey () const

Returns the key for the current iterator item.

bool QIntCacheIterator::isEmpty () const

Returns TRUE if the cache is empty; otherwise returns FALSE.

See also count().

QIntCacheIterator::operator type * () const

Cast operator. Returns a pointer to the current iterator item. Same as current().

type * QIntCacheIterator::operator() ()

Makes the succeeding item current and returns the original current item.

If the current iterator item was the last item in the cache or if it was null, null is returned.

type * QIntCacheIterator::operator++ ()

Prefix ++ makes the iterator point to the item just after current(), and makes it the new current item for the iterator. If current() was the last item, operator--() returns 0.

type * QIntCacheIterator::operator+= ( uintjump )

Returns the item jump positions after the current item, or null if it is beyond the last item. Makes this the current item.

type * QIntCacheIterator::operator-- ()

Prefix -- makes the iterator point to the item just before current(), and makes it the new current item for the iterator. If current() was the first item, operator--() returns 0.

type * QIntCacheIterator::operator-= ( uintjump )

Returns the item jump positions before the current item, or null if it is beyond the first item. Makes this the current item.

QIntCacheIterator<type>& QIntCacheIterator::operator= ( constQIntCacheIterator<type>&ci )

Makes this an iterator for the same cache as ci. The new iterator starts at the same item as ci.current(), but moves independently thereafter.

type * QIntCacheIterator::toFirst ()

Sets the iterator to point to the first item in the cache and returns a pointer to the item.

Sets the iterator to null and returns null if if the cache is empty.

See also toLast() and isEmpty().

type * QIntCacheIterator::toLast ()

Sets the iterator to point to the last item in the cache and returns a pointer to the item.

Sets the iterator to null and returns null if if the cache is empty.

See also toFirst() and isEmpty().

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