#include <lists.h>
Inheritance diagram for PAbstractList:
Public Member Functions | |
virtual Comparison | Compare (const PObject &obj) const |
Overrides from class PContainer | |
virtual PBoolean | SetSize (PINDEX newSize) |
Overrides from class PCollection | |
virtual PINDEX | Append (PObject *obj) |
virtual PINDEX | Insert (const PObject &before, PObject *obj) |
virtual PINDEX | InsertAt (PINDEX index, PObject *obj) |
virtual PBoolean | Remove (const PObject *obj) |
virtual PObject * | RemoveAt (PINDEX index) |
virtual PBoolean | SetAt (PINDEX index, PObject *val) |
virtual PBoolean | ReplaceAt (PINDEX index, PObject *val) |
virtual PObject * | GetAt (PINDEX index) const |
virtual PINDEX | GetObjectsIndex (const PObject *obj) const |
virtual PINDEX | GetValuesIndex (const PObject &obj) const |
Protected Types | |
typedef PListElement | Element |
Protected Member Functions | |
PINLINE PObject & | GetReferenceAt (PINDEX index) const |
PBoolean | SetCurrent (PINDEX index, PListElement *&lastElement) const |
PObject * | RemoveElement (PListElement *element) |
Protected Attributes | |
PListInfo * | info |
The implementation of a list allows very fast inserting and deleting of objects in the collection, but has severe penalties for random access. All object access should be done sequentially to avoid these speed penalties.
The class remembers the last accessed element. This state information is used to optimise access by the "virtual array" model of collections. If access via ordinal index is made sequentially there is little overhead.
The PAbstractList class would very rarely be descended from directly by the user. The PDECLARE_LIST# and PLIST# macros would normally be used to create descendent classes. They will instantiate the template based on PList# or directly declare and define the class (using inline functions) if templates are not being used.
The PList# class or PDECLARE_LIST# macro will define the correctly typed operators for subscript access (operator[]#).
typedef PListElement PAbstractList::Element [protected] |
PINLINE PAbstractList::PAbstractList | ( | ) |
Create a new, empty, list.
Note that by default, objects placed into the list will be deleted when removed or when all references to the list are destroyed.
PINLINE PAbstractList::PAbstractList | ( | ) |
Create a new, empty, list.
Note that by default, objects placed into the list will be deleted when removed or when all references to the list are destroyed.
virtual Comparison PAbstractList::Compare | ( | const PObject & | obj | ) | const [virtual] |
Get the relative rank of the two lists. The following algorithm is employed for the comparison: {description} [EqualTo#] if the two lists are identical in length and each objects values, not pointer, are equal.
[LessThan#] if the instances object value at an ordinal position is less than the corresponding objects value in the obj# parameters list.
This is also returned if all objects are equal and the instances list length is less than the obj# parameters list length.
[GreaterThan#] if the instances object value at an ordinal position is greater than the corresponding objects value in the obj# parameters list.
This is also returned if all objects are equal and the instances list length is greater than the obj# parameters list length. {description}
Reimplemented from PObject.
virtual PBoolean PAbstractList::SetSize | ( | PINDEX | newSize | ) | [virtual] |
This function is meaningless for lists. The size of the collection is determined by the addition and removal of objects. The size cannot be set in any other way.
newSize | New size for the list, this is ignored. |
Implements PContainer.
virtual PINDEX PAbstractList::Append | ( | PObject * | obj | ) | [virtual] |
Append a new object to the collection. This places a new link at the "tail" of the list.
obj | New object to place into the collection. |
Implements PCollection.
Insert a new object immediately before the specified object. If the object to insert before is not in the collection then the equivalent of the Append()# function is performed.
Note that the object values are compared for the search of the before# parameter, not the pointers. So the objects in the collection must correctly implement the PObject::Compare()# function.
before | Object value to insert before. |
obj | New object to place into the collection. |
Implements PCollection.
virtual PINDEX PAbstractList::InsertAt | ( | PINDEX | index, | |
PObject * | obj | |||
) | [virtual] |
Insert a new object at the specified ordinal index. If the index is greater than the number of objects in the collection then the equivalent of the Append()# function is performed.
index | Index position in collection to place the object. |
obj | New object to place into the collection. |
Implements PCollection.
Remove the object from the collection. If the AllowDeleteObjects option is set then the object is also deleted.
obj | Existing object to remove from the collection. |
Implements PCollection.
virtual PObject* PAbstractList::RemoveAt | ( | PINDEX | index | ) | [virtual] |
Remove the object at the specified ordinal index from the collection. If the AllowDeleteObjects option is set then the object is also deleted.
Note if the index is beyond the size of the collection then the function will assert.
index | Index position in collection to place the object. |
Implements PCollection.
Set the object at the specified ordinal position to the new value. This will overwrite the existing entry. This method will NOT delete the old object independently of the AllowDeleteObjects option. Use ReplaceAt()# instead.
Note if the index is beyond the size of the collection then the function will assert.
index | Index position in collection to set. |
val | New value to place into the collection. |
Implements PCollection.
Set the object at the specified ordinal position to the new value. This will overwrite the existing entry. If the AllowDeleteObjects option is set then the old object is also deleted.
Note if the index is beyond the size of the collection then the function will assert.
index | Index position in collection to set. |
val | New value to place into the collection. |
virtual PObject* PAbstractList::GetAt | ( | PINDEX | index | ) | const [virtual] |
Get the object at the specified ordinal position. If the index was greater than the size of the collection then NULL is returned.
The object accessed in this way is remembered by the class and further access will be fast. Access to elements one either side of that saved element, and the head and tail of the list, will always be fast.
index | Index position in the collection of the object. |
Implements PCollection.
virtual PINDEX PAbstractList::GetObjectsIndex | ( | const PObject * | obj | ) | const [virtual] |
Search the collection for the specific instance of the object. The object pointers are compared, not the values. A simple linear search from "head" of the list is performed.
obj | Object to find. |
Implements PCollection.
virtual PINDEX PAbstractList::GetValuesIndex | ( | const PObject & | obj | ) | const [virtual] |
Search the collection for the specified value of the object. The object values are compared, not the pointers. So the objects in the collection must correctly implement the PObject::Compare()# function. A simple linear search from "head" of the list is performed.
obj | Object to find value of. |
Implements PCollection.
PINLINE PObject & PAbstractList::GetReferenceAt | ( | PINDEX | index | ) | const [protected] |
Get the object at the specified ordinal position. If the index was greater than the size of the collection then this asserts.
The object accessed in this way is remembered by the class and further access will be fast. Access to elements one either side of that saved element, and the head and tail of the list, will always be fast.
index | Ordinal index of the list element to set as current. |
PBoolean PAbstractList::SetCurrent | ( | PINDEX | index, | |
PListElement *& | lastElement | |||
) | const [protected] |
Move the internal "cursor" to the index position specified. This function will optimise the sequential move taking into account the previous current position and the position at the head and tail of the list. Whichever of these three points is closes is used as the starting point for a sequential move to the required index.
index | Ordinal index of the list element to set as current. |
lastElement | pointer to final element |
PObject* PAbstractList::RemoveElement | ( | PListElement * | element | ) | [protected] |
PListInfo* PAbstractList::info [protected] |