Tools.h++ Class Reference

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©Copyright 1996 Rogue Wave Software
RWHashTable
RWHashTable RWCollection RWCollectable
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Synopsis
#include <rw/hashtab.h>
RWHashTable h ;
Description
This class is a simple hash table for objects inheriting from RWCollectable. It uses chaining (as
implemented by class RWSlistCollectables) to resolve hash collisions. Duplicate objects are
allowed.
An object stored by RWHashTable must inherit from the abstract base class RWCollectable,
with suitable definition for virtual functions hash() and isEqual() (see class RWCollectable).
To find an object that matches a key, the key's virtual function hash() is first called to determine
in which bucket the object occurs. The bucket is then searched linearly by calling the virtual
function isEqual() for each candidate, with the key as the argument. The first object to return
TRUE is the returned object.
The initial number of buckets in the table is set by the constructor. There is a default value. If
the number of items in the collection greatly exceeds the number of buckets then efficiency will