michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef nsClassHashtable_h__
michael@0: #define nsClassHashtable_h__
michael@0: 
michael@0: #include "nsBaseHashtable.h"
michael@0: #include "nsHashKeys.h"
michael@0: #include "nsAutoPtr.h"
michael@0: 
michael@0: /**
michael@0:  * templated hashtable class maps keys to C++ object pointers.
michael@0:  * See nsBaseHashtable for complete declaration.
michael@0:  * @param KeyClass a wrapper-class for the hashtable key, see nsHashKeys.h
michael@0:  *   for a complete specification.
michael@0:  * @param Class the class-type being wrapped
michael@0:  * @see nsInterfaceHashtable, nsClassHashtable
michael@0:  */
michael@0: template<class KeyClass,class T>
michael@0: class nsClassHashtable :
michael@0:   public nsBaseHashtable< KeyClass, nsAutoPtr<T>, T* >
michael@0: {
michael@0: public:
michael@0:   typedef typename KeyClass::KeyType KeyType;
michael@0:   typedef T* UserDataType;
michael@0:   typedef nsBaseHashtable< KeyClass, nsAutoPtr<T>, T* > base_type;
michael@0: 
michael@0:   nsClassHashtable()
michael@0:   {
michael@0:   }
michael@0:   explicit nsClassHashtable(uint32_t aInitSize)
michael@0:     : nsBaseHashtable<KeyClass,nsAutoPtr<T>,T*>(aInitSize)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * @copydoc nsBaseHashtable::Get
michael@0:    * @param pData if the key doesn't exist, pData will be set to nullptr.
michael@0:    */
michael@0:   bool Get(KeyType aKey, UserDataType* pData) const;
michael@0: 
michael@0:   /**
michael@0:    * @copydoc nsBaseHashtable::Get
michael@0:    * @returns nullptr if the key is not present.
michael@0:    */
michael@0:   UserDataType Get(KeyType aKey) const;
michael@0: 
michael@0:   /**
michael@0:    * Remove the entry for the given key from the hashtable and return it in
michael@0:    * aOut.  If the key is not in the hashtable, aOut's pointer is set to
michael@0:    * nullptr.
michael@0:    *
michael@0:    * Normally, an entry is deleted when it's removed from an nsClassHashtable,
michael@0:    * but this function transfers ownership of the entry back to the caller
michael@0:    * through aOut -- the entry will be deleted when aOut goes out of scope.
michael@0:    *
michael@0:    * @param aKey the key to get and remove from the hashtable
michael@0:    */
michael@0:   void RemoveAndForget(KeyType aKey, nsAutoPtr<T> &aOut);
michael@0: };
michael@0: 
michael@0: //
michael@0: // nsClassHashtable definitions
michael@0: //
michael@0: 
michael@0: template<class KeyClass,class T>
michael@0: bool
michael@0: nsClassHashtable<KeyClass,T>::Get(KeyType aKey, T** retVal) const
michael@0: {
michael@0:   typename base_type::EntryType* ent = this->GetEntry(aKey);
michael@0: 
michael@0:   if (ent)
michael@0:   {
michael@0:     if (retVal)
michael@0:       *retVal = ent->mData;
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   if (retVal)
michael@0:     *retVal = nullptr;
michael@0: 
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: template<class KeyClass,class T>
michael@0: T*
michael@0: nsClassHashtable<KeyClass,T>::Get(KeyType aKey) const
michael@0: {
michael@0:   typename base_type::EntryType* ent = this->GetEntry(aKey);
michael@0: 
michael@0:   if (!ent)
michael@0:     return nullptr;
michael@0: 
michael@0:   return ent->mData;
michael@0: }
michael@0: 
michael@0: template<class KeyClass,class T>
michael@0: void
michael@0: nsClassHashtable<KeyClass,T>::RemoveAndForget(KeyType aKey, nsAutoPtr<T> &aOut)
michael@0: {
michael@0:   aOut = nullptr;
michael@0:   nsAutoPtr<T> ptr;
michael@0: 
michael@0:   typename base_type::EntryType *ent = this->GetEntry(aKey);
michael@0:   if (!ent)
michael@0:     return;
michael@0: 
michael@0:   // Transfer ownership from ent->mData into aOut.
michael@0:   aOut = ent->mData;
michael@0: 
michael@0:   this->Remove(aKey);
michael@0: }
michael@0: 
michael@0: #endif // nsClassHashtable_h__