From 87d29563e3ccdeb7fea0197e262e667ef323ff9c Mon Sep 17 00:00:00 2001 From: Michele Calgaro Date: Sun, 7 Jul 2024 14:56:09 +0900 Subject: Rename utility class nt* related files to equivalent tq* Signed-off-by: Michele Calgaro --- doc/html/tqintcache.html | 242 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 242 insertions(+) create mode 100644 doc/html/tqintcache.html (limited to 'doc/html/tqintcache.html') diff --git a/doc/html/tqintcache.html b/doc/html/tqintcache.html new file mode 100644 index 000000000..9dbde7950 --- /dev/null +++ b/doc/html/tqintcache.html @@ -0,0 +1,242 @@ + + + + + +TQIntCache Class + + + + + + + +

TQIntCache Class Reference

+ +

The TQIntCache class is a template class that provides a cache based on long keys. +More... +

#include <tqintcache.h> +

Inherits TQPtrCollection. +

List of all member functions. +

Public Members

TQIntCache ( int maxCost = 100, int size = 17 )
~TQIntCache ()
int maxCost () const
int totalCost () const
void setMaxCost ( int m )
virtual uint count () const
uint size () const
bool isEmpty () const
bool insert ( long k, const type * d, int c = 1, int p = 0 )
bool remove ( long k )
type * take ( long k )
virtual void clear ()
type * find ( long k, bool ref = TRUE ) const
type * operator[] ( long k ) const
void statistics () const

Detailed Description

+ + +The TQIntCache class is a template class that provides a cache based on long keys. +

+ +

TQIntCache is implemented as a template class. Define a template +instance TQIntCache<X> to create a cache that operates on +pointers to X, or X*. +

A cache is a least recently used (LRU) list of cache items, +accessed via long keys. Each cache item has a cost. The sum +of item costs, totalCost(), will not exceed the maximum cache +cost, maxCost(). If inserting a new item would cause the total +cost to exceed the maximum cost, the least recently used items in +the cache are removed. +

Apart from insert(), by far the most important function is find() +(which also exists as operator[]). This function looks up an +item, returns it, and by default marks it as being the most +recently used item. +

There are also methods to remove() or take() an object from the +cache. Calling setAutoDelete(TRUE) for a cache tells it to delete +items that are removed. The default is to not delete items when +they are removed (i.e. remove() and take() are equivalent). +

When inserting an item into the cache, only the pointer is copied, +not the item itself. This is called a shallow copy. It is possible +to make the cache copy all of the item's data (known as a deep copy) when an item is inserted. insert() calls the virtual +function TQPtrCollection::newItem() for the item to be inserted. +Inherit a dictionary and reimplement newItem() if you want deep +copies. +

When removing a cache item, the item will be automatically +deleted if auto-deletion is enabled. +

There is a TQIntCacheIterator which may be used to traverse the +items in the cache in arbitrary order. +

Member Function Documentation

TQIntCache::TQIntCache ( int maxCost = 100, int size = 17 ) +

+ +

Constructs a cache whose contents will never have a total cost +greater than maxCost and which is expected to contain less than +size items. +

size is actually the size of an internal hash array; it's +usually best to make it prime and at least 50% bigger than the +largest expected number of items in the cache. +

Each inserted item is associated with a cost. When inserting a new +item, if the total cost of all items in the cache will exceed maxCost, the cache will start throwing out the older (least +recently used) items until there is enough room for the new item +to be inserted. + +

TQIntCache::~TQIntCache () +

+ +

Removes all items from the cache and then destroys the int cache. +If auto-deletion is enabled the cache's items are deleted. All +iterators that access this cache will be reset. + +

void TQIntCache::clear () `[virtual]` +

+ +

Removes all items from the cache, and deletes them if +auto-deletion has been enabled. +

All cache iterators that operate this on cache are reset. +

uint TQIntCache::count () const `[virtual]` +

+ +

Returns the number of items in the cache. +

type * TQIntCache::find ( long k, bool ref = TRUE ) const +

+ +

Returns the item associated with k, or 0 if the key does not +exist in the cache. If ref is TRUE (the default), the item is +moved to the front of the least recently used list. +

If there are two or more items with equal keys, the one that was +inserted most recently is returned. + +

bool TQIntCache::insert ( long k, const type * d, int c = 1, int p = 0 ) +

+ +

Inserts the item d into the cache with key k and assigns it +a cost of c (default 1). Returns TRUE if it succeeds; otherwise +returns FALSE. +

The cache's size is limited, and if the total cost is too high, +TQIntCache will remove old, least-used items until there is room +for this new item. +

The parameter p is internal and should be left at the default +value (0). +

Warning: If this function returns FALSE (for example, the cost , +exceeds maxCost()), you must delete d yourself. Additionally, +be very careful about using d after calling this function. Any +other insertions into the cache, from anywhere in the application +or within TQt itself, could cause the object to be discarded from +the cache and the pointer to become invalid. + +

bool TQIntCache::isEmpty () const +

+ +

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

int TQIntCache::maxCost () const +

+ +

Returns the maximum allowed total cost of the cache. +

See also setMaxCost() and totalCost(). + +

type * TQIntCache::operator[] ( long k ) const +

+ +

Returns the item associated with k, or 0 if k does not exist +in the cache, and moves the item to the front of the least +recently used list. +

If there are two or more items with equal keys, the one that was +inserted most recently is returned. +

This is the same as find( k, TRUE ). +

bool TQIntCache::remove ( long k ) +

+ +

Removes the item associated with k, and returns TRUE if the +item was present in the cache; otherwise returns FALSE. +

The item is deleted if auto-deletion has been enabled, i.e. if you +have called setAutoDelete(TRUE). +

If there are two or more items with equal keys, the one that was +inserted most recently is removed. +

All iterators that refer to the removed item are set to point to +the next item in the cache's traversal order. +

void TQIntCache::setMaxCost ( int m ) +

+ +

Sets the maximum allowed total cost of the cache to m. If the +current total cost is greater than m, some items are removed +immediately. +

uint TQIntCache::size () const +

+ +

Returns the size of the hash array used to implement the cache. +This should be a bit larger than count() is likely to be. + +

void TQIntCache::statistics () const +

+ +

A debug-only utility function. Prints out cache usage, hit/miss, +and distribution information using tqDebug(). This function does +nothing in the release library. + +

type * TQIntCache::take ( long k ) +

+ +

Takes the item associated with k out of the cache without +deleting it, and returns a pointer to the item taken out or 0 if +the key does not exist in the cache. +

If there are two or more items with equal keys, the one that was +inserted most recently is taken. +

All iterators that refer to the taken item are set to point to the +next item in the cache's traversal order. +

int TQIntCache::totalCost () const +

+ +

Returns the total cost of the items in the cache. This is an +integer in the range 0 to maxCost(). +