pjs/xpcom/ds/nsHashtable.h

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
 * Reserved.
 */

#ifndef nsHashtable_h__
#define nsHashtable_h__

#include "plhash.h"
#include "nsCom.h"

class NS_COM nsHashKey {
protected:
  nsHashKey(void);
public:
  virtual ~nsHashKey(void);
  virtual PRUint32 HashValue(void) const = 0;
  virtual PRBool Equals(const nsHashKey *aKey) const = 0;
  virtual nsHashKey *Clone(void) const = 0;
};

// Enumerator callback function. Use

typedef PRBool (*nsHashtableEnumFunc)(nsHashKey *aKey, void *aData, void* closure);

class NS_COM nsHashtable {
private:
  // members  
  PLHashTable *hashtable;

public:
  nsHashtable(PRUint32 aSize = 256);
  ~nsHashtable();

  PRInt32 Count(void) { return hashtable->nentries; }
  void *Put(nsHashKey *aKey, void *aData);
  void *Get(nsHashKey *aKey);
  void *Remove(nsHashKey *aKey);
  nsHashtable *Clone();
  void Enumerate(nsHashtableEnumFunc aEnumFunc, void* closure = NULL);
  void Reset();
};

////////////////////////////////////////////////////////////////////////////////
// nsISupportsKey: Where keys are nsISupports objects that get refcounted.

#include "nsISupports.h"

class nsISupportsKey : public nsHashKey {
private:
    nsISupports* mKey;
  
public:
    nsISupportsKey(nsISupports* key) {
        mKey = key;
        NS_IF_ADDREF(mKey);
    }
  
    ~nsISupportsKey(void) {
        NS_IF_RELEASE(mKey);
    }
  
    PRUint32 HashValue(void) const {
        return (PRUint32)mKey;
    }

    PRBool Equals(const nsHashKey *aKey) const {
        return (mKey == ((nsISupportsKey *) aKey)->mKey);
    }

    nsHashKey *Clone(void) const {
        return new nsISupportsKey(mKey);
    }
};

////////////////////////////////////////////////////////////////////////////////
// nsVoidKey: Where keys are void* objects that don't get refcounted.

class nsVoidKey : public nsHashKey {
private:
    const void* mKey;
  
public:
    nsVoidKey(const void* key) {
        mKey = key;
    }
  
    PRUint32 HashValue(void) const {
        return (PRUint32)mKey;
    }

    PRBool Equals(const nsHashKey *aKey) const {
        return (mKey == ((const nsVoidKey *) aKey)->mKey);
    }

    nsHashKey *Clone(void) const {
        return new nsVoidKey(mKey);
    }
};

////////////////////////////////////////////////////////////////////////////////
// nsIDKey: Where keys are nsIDs (e.g. nsIID, nsCID).

#include "nsID.h"

class nsIDKey : public nsHashKey {
private:
    nsID mID;
  
public:
    nsIDKey(const nsID &aID) {
        mID = aID;
    }
  
    PRUint32 HashValue(void) const {
        return mID.m0;
    }

    PRBool Equals(const nsHashKey *aKey) const {
        return (mID.Equals(((const nsIDKey *) aKey)->mID));
    }

    nsHashKey *Clone(void) const {
        return new nsIDKey(mID);
    }
};

#endif