RWTPtrMultiMap(3C++) RWTPtrMultiMap(3C++)
Name
RWTPtrMultiMap<K,T,C> - Rogue Wave library class
Synopsis
#include <rw/tpmmap.h>
RWTPtrMultiMap<K,T,C> m;
Standard C++ Library Dependent!RWTPtrMultiMap requires the Standard C++ Library.
Description
This class maintains a pointer-based collection of associations of type
pair<K*, const T*>. The first part of the association is a key of type
K*, the second is its associated item of type T*. Order is determined by
the key according to a comparison object of type C. C must induce a
total ordering on elements of type K via a public member
bool operator()(const K& x, const K& y)
which returns true if x and its partner should precede y and its partner
within the collection. The structure less<T> from the C++-standard
header file <functional> is an example. Note that keys will be
dereferenced before being compared. RWTPtrMultiMap<K,T,C> may contain
multiple keys that compare equal to each other. (RWTPtrMap<K,T,C> will
not accept a key that compares equal to any key already in the
collection.) Equality is based on the comparison object and not on the
== operator. Given a comparison object comp, keys a and b are equal if
!comp(a,b) && !comp(b,a).
Persistence
Isomorphic.
Examples
In this example, a multimap of RWCStrings and RWDates is exercised.
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//
// tpmmap.cpp
//
#include <rw/tpmmap.h>
#include <rw/cstring.h>
#include <rw/rwdate.h>
#include <iostream.h>
main(){
typedef RWTPtrMultiMap<RWCString, RWDate, less<RWCString> >
RWMMap;
RWMMap birthdays;
birthdays.insert(new RWCString("John"),
new RWDate(12, "April", 1975));
birthdays.insert(new RWCString("Ivan"),
new RWDate(2, "Nov", 1980));
birthdays.insert(new RWCString("Mary"),
new RWDate(22, "Oct", 1987));
birthdays.insert(new RWCString("Ivan"),
new RWDate(19, "June", 1971));
birthdays.insert(new RWCString("Sally"),
new RWDate(15, "March", 1976));
birthdays.insert(new RWCString("Ivan"),
new RWDate(6, "July", 1950));
// How many "Ivan"s?
RWCString ivanstr("Ivan");
RWMMap::size_type n = birthdays.occurrencesOf(&ivanstr);
RWMMap::size_type idx = 0;
cout << "There are " << n << " Ivans:" << endl;
RWMMap::const_iterator iter =
birthdays.std().lower_bound(&ivanstr);
while (++idx <= n)
cout << idx << ". " << *(*iter++).second << endl;
return 0;
}
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Program Output:
There are 3 Ivans:
1. 11/02/80
2. 06/19/71
3. 07/06/50
Related Classes
Class RWTPtrMap<K,T,C> offers the same interface to a pointer-based
collection that will not accept multiple keys that compare equal to each
other. RWTPtrMultiSet<T,C> maintains a pointer-based collection of keys
without the associated values. Class
multimap<K*,T*,deref_compare<C,K,allocator> > is the C++-standard
collection that serves as the underlying implementation for this
collection.
Public Typedefs
typedef rw_deref_compare<C,K> container_comp;
typedef multimap<K*,T*,container_comp,allocator>
container_type;
typedef container_type::size_type size_type;
typedef container_type::difference_type difference_type;
typedef container_type::iterator iterator;
typedef container_type::const_iterator const_iterator;
typedef pair<K* const, T*> value_type;
typedef pair<K* const, T*> reference;
typedef const pair<K* const, T*>& const_reference;
typedef K* value_type_key;
typedef T* value_type_data;
typedef K*& reference_key;
typedef T*& reference_data;
typedef const K*const& const_reference_key;
typedef const T*const& const_reference_data;
Public Constructors
RWTPtrMultiMap<K,T,C>
(const container_comp& comp =container_comp());
Constructs an empty map with comparator comp.
RWTPtrMultiMap<K,T,C>(const container_type& m);
Constructs a multimap by copying all element from m.
RWTPtrMultiMap<K,T,C>(const RWTPtrMultiMap<K,T,C>& rwm);
Copy constructor.
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RWTPtrMultiMap<K,T,C>(value_type* first,value_type* last,
const container_comp& comp = container_comp());
Constructs a multimap by copying elements from the array of pairs pointed
to by first, up to, but not including, the pair pointed to by last.
Public Member Operators
RWTPtrMultiMap<K,T,C>&
operator=(const container_type& m);
RWTPtrMultiMap<K,T,C>&
operator=(const RWTPtrMultiMap<K,T,C>& m);
Destroys all associations in self and replaces them by copying all
associations from m.
bool
operator<(const RWTPtrMultiMap<K,T,C>& m);
Returns true if self compares lexicographically less than m, otherwise
returns false. Keys in each collection are dereferenced before being
compared. Assumes that type K has well-defined less-than semantics.
bool
operator==(const RWTPtrMultiMap<K,T,C>& m);
Returns true if self compares equal to m, otherwise returns false. Two
collections are equal if both have the same number of entries, and
iterating through both collections produces, in turn, individual keys
that compare equal to each other. Keys are dereferenced before being
compared.
Public Member Functions
void
apply(void (*fn)(const K*, T*&,void*),void* d);
void
apply(void (*fn)(const K*,const T*,void*),void* d) const;
Applies the user-defined function pointed to by fn to every association
in the collection. This function must have one of the prototypes:
void yourfun(const K* key, T*& a, void* d);
void yourfun(const K* key, const T* a, void* d);
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Client data may be passed through parameter d.
void
applyToKeyAndValue(void (*fn)(const K*, T*&,void*),void* d);
void
applyToKeyAndValue
(void (*fn)(const K*,const T*,void*),void* d) const;
This is a deprecated version of the apply member above. It behaves
exactly the same as apply.
iterator
begin();
const_iterator
begin() const;
Returns an iterator positioned at the first pair in self.
void
clear();
Clears the collection by removing all items from self.
void
clearAndDestroy();
Removes all associations from the collection and uses operator delete to
destroy the objects pointed to by the keys and their associated items.
Do not use this method if multiple pointers to the same object are
stored.
bool
contains(const K* key) const;
Returns true if there exists a key j in self that compares equal to *key,
otherwise returns false.
bool
contains(bool (*fn)(value_type,void*), void* d) const;
Returns true if there exists an association a in self such that the
expression ((*fn)(a,d)) is true, otherwise returns false. fn points to a
user-defined tester function which must have prototype:
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bool yourTester(value_type a, void* d);
Client data may be passed through parameter d.
iterator
end();
const_iterator
end() const;
Returns an iterator positioned "just past" the last association in self.
size_type
entries() const;
Returns the number of associations in self.
const K*
find(const K* key) const;
If there exists a key j in self that compares equal to *key, then j is
returned. Otherwise, returns rwnil.
value_type
find(bool (*fn)(value_type,void*), void* d) const;
If there exists an association a in self such that the expression
((*fn)(a,d)) is true, then returns a. Otherwise, returns
pair<rwnil,rwnil>. fn points to a user-defined tester function which
must have prototype:
bool yourTester(value_type a, void* d);
Client data may be passed through parameter d.
T*
findValue(const K* key);
const T*
findValue(const K* key) const;
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If there exists a key j in self such that the expression (*j == *key) is
true, returns the item associated with j. Otherwise, returns rwnil.
const K*
findKeyAndValue(const K* key, T*& tr);
const K*
findKeyAndValue(const K* key, const T*& tr) const;
If there exists a key j in self that compares equal to *key, assigns the
item associated with j to tr, and returns j. Otherwise, returns rwnil
and leaves the value of tr unchanged.
bool
insert(K* key, T* a);
Adds key with associated item a to the collection. Returns true.
bool
insertKeyAndValue(K* key, T* a);
This is a deprecated version of the insert member above. It behaves
exactly the same as insert.
bool
isEmpty() const;
Returns true if there are no items in the collection, false otherwise.
size_type
occurrencesOf(const K* key) const;
Returns the number of keys j in self that compare equal to *key.
size_type
occurrencesOf
(bool (*fn)(value_type,void*), void* d) const;
Returns the number of associations a in self such that the
expression((*fn)(a,d)) is true. fn points to a user-defined tester
function which must have prototype:
bool yourTester(value_type a, void* d);
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Client data may be passed through parameter d.
K*
remove(const K* key);
Removes the first association with key j in self such that the expression
(*j == *key) is true and returns j. Returns rwnil if there is no such
association.
K*
remove(bool (*fn)(value_type,void*), void* d);
Removes the first association a in self such that the expression
((*fn)(a,d)) is true and returns its key. Returns rwnil if there is no
such association. fn points to a user-defined tester function which must
have prototype:
bool yourTester(value_type a, void* d);
Client data may be passed through parameter d.
size_type
removeAll(const K* key);
Removes all associations with key j in self that compare equal to *key.
Returns the number of associations removed.
size_type
removeAll(bool (*fn)(value_type,void*), void* d);
Removes all associations a in self such that the expression
((*fn)(a,d))is true. Returns the number removed. fn points to a user-
defined tester function which must have prototype:
bool yourTester(value_type a, void* d);
Client data may be passed through parameter d.
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container_type&
std();
const container_type&
std() const;
Returns a reference to the underlying C++-standard collection that serves
as the implementation for self.
Related Global Operators
RWvostream&
operator<<(RWvostream& strm,
const RWTPtrMultiMap<K,T,C>& coll);
RWFile&
operator<<(RWFile& strm,
const RWTPtrMultiMap<K,T,C>& coll);
Saves the collection coll onto the output stream strm, or a reference to
it if it has already been saved.
RWvistream&
operator>>(RWvistream& strm, RWTPtrMultiMap<K,T,C>& coll);
RWFile&
operator>>(RWFile& strm, RWTPtrMultiMap<K,T,C>& coll);
Restores the contents of the collection coll from the input stream strm.
RWvistream&
operator>>(RWvistream& strm, RWTPtrMultiMap<K,T,C>*& p);
RWFile&
operator>>(RWFile& strm, RWTPtrMultiMap<K,T,C>*& p);
Looks at the next object on the input stream strm and either creates a
new collection off the heap and sets p to point to it, or sets p to point
to a previously read instance. If a collection is created off the heap,
then you are responsible for deleting it.
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