gecko-dev/xpcom/ds/nsHashSets.h
2004-04-18 14:21:17 +00:00

108 lines
4.3 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef __nsHashSets_h__
#define __nsHashSets_h__
#include "nsDoubleHashtable.h"
/*
* HASH SETS
*
* These hash classes describe hashtables that contain keys without values.
* This is useful when you want to store things and then just test for their
* existence later. We have defined standard ones for string, int and void.
*
* nsStringHashSet: nsAString&
* nsCStringHashSet: nsACString&
* nsInt32HashSet: PRInt32
* nsVoidHashSet: void*
*
* USAGE:
* Put(): put a thing of the given type into the set
* Contains(): whether it contains a thing of the given type
* To use, you just do: (for example)
*
* #include "nsDoubleHashtable.h"
* nsInt32HashSet mySet;
* mySet.Init(1);
* mySet.Put(5);
* if (mySet.Contains(5)) {
* printf("yay\n");
* }
*
* There is a nice convenient macro for declaring empty map classes:
* DECL_DHASH_SET(CLASSNAME, ENTRY_CLASS, KEY_TYPE)
* - CLASSNAME: the name of the class
* - ENTRY_CLASS: the name of the entry class with the key in it
* - KEY_TYPE: the type of key for Put() and Contains()
*
* DHASH_SET(CLASSNAME, ENTRY_CLASS, KEY_TYPE) is the companion macro
* you must put in the .cpp (implementation) code.
*/
#define DECL_DHASH_SET(CLASSNAME,ENTRY_CLASS,KEY_TYPE) \
DECL_DHASH_WRAPPER(CLASSNAME##Super,ENTRY_CLASS,KEY_TYPE) \
class DHASH_EXPORT CLASSNAME : public CLASSNAME##Super { \
public: \
CLASSNAME() : CLASSNAME##Super() { } \
~CLASSNAME() { } \
nsresult Put(const KEY_TYPE aKey) { \
return AddEntry(aKey) ? NS_OK : NS_ERROR_OUT_OF_MEMORY; \
} \
PRBool Contains(const KEY_TYPE aKey) { \
return GetEntry(aKey) ? PR_TRUE : PR_FALSE; \
} \
};
#define DHASH_SET(CLASSNAME,ENTRY_CLASS,KEY_TYPE) \
DHASH_WRAPPER(CLASSNAME##Super,ENTRY_CLASS,KEY_TYPE)
#undef DHASH_EXPORT
#define DHASH_EXPORT NS_COM
DECL_DHASH_SET(nsStringHashSet, PLDHashStringEntry, nsAString&)
DECL_DHASH_SET(nsCStringHashSet,PLDHashCStringEntry,nsACString&)
DECL_DHASH_SET(nsInt32HashSet, PLDHashInt32Entry, PRInt32)
DECL_DHASH_SET(nsVoidHashSet, PLDHashVoidEntry, void*)
#undef DHASH_EXPORT
#define DHASH_EXPORT
#endif