mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-31 22:25:30 +00:00
160 lines
4.1 KiB
C++
160 lines
4.1 KiB
C++
/* -*- Mode: C++; tab-width: 2; 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.
|
|
*/
|
|
|
|
#include "nsIEnumerator.h"
|
|
|
|
class nsConjoiningEnumerator : public nsIBidirectionalEnumerator
|
|
{
|
|
public:
|
|
NS_DECL_ISUPPORTS
|
|
|
|
// nsIEnumerator methods:
|
|
NS_IMETHOD First(void);
|
|
NS_IMETHOD Next(void);
|
|
NS_IMETHOD CurrentItem(nsISupports **aItem);
|
|
NS_IMETHOD IsDone(void);
|
|
|
|
// nsIBidirectionalEnumerator methods:
|
|
NS_IMETHOD Last(void);
|
|
NS_IMETHOD Prev(void);
|
|
|
|
// nsConjoiningEnumerator methods:
|
|
nsConjoiningEnumerator(nsIEnumerator* first, nsIEnumerator* second);
|
|
virtual ~nsConjoiningEnumerator(void);
|
|
|
|
protected:
|
|
nsIEnumerator* mFirst;
|
|
nsIEnumerator* mSecond;
|
|
nsIEnumerator* mCurrent;
|
|
};
|
|
|
|
nsConjoiningEnumerator::nsConjoiningEnumerator(nsIEnumerator* first, nsIEnumerator* second)
|
|
: mFirst(first), mSecond(second), mCurrent(first)
|
|
{
|
|
NS_ADDREF(mFirst);
|
|
NS_ADDREF(mSecond);
|
|
}
|
|
|
|
nsConjoiningEnumerator::~nsConjoiningEnumerator(void)
|
|
{
|
|
NS_RELEASE(mFirst);
|
|
NS_RELEASE(mSecond);
|
|
}
|
|
|
|
NS_IMPL_ADDREF(nsConjoiningEnumerator);
|
|
NS_IMPL_RELEASE(nsConjoiningEnumerator);
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator::QueryInterface(REFNSIID aIID, void** aInstancePtr)
|
|
{
|
|
if (NULL == aInstancePtr)
|
|
return NS_ERROR_NULL_POINTER;
|
|
|
|
if (aIID.Equals(nsIBidirectionalEnumerator::IID()) ||
|
|
aIID.Equals(nsIEnumerator::IID()) ||
|
|
aIID.Equals(nsISupports::IID())) {
|
|
*aInstancePtr = (void*) this;
|
|
NS_ADDREF_THIS();
|
|
return NS_OK;
|
|
}
|
|
return NS_NOINTERFACE;
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator::First(void)
|
|
{
|
|
mCurrent = mFirst;
|
|
return mCurrent->First();
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator:: Next(void)
|
|
{
|
|
nsresult rv = mCurrent->Next();
|
|
if (NS_FAILED(rv) && mCurrent == mFirst) {
|
|
mCurrent = mSecond;
|
|
rv = mCurrent->First();
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator:: CurrentItem(nsISupports **aItem)
|
|
{
|
|
return mCurrent->CurrentItem(aItem);
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator:: IsDone(void)
|
|
{
|
|
return (mCurrent == mFirst && mCurrent->IsDone())
|
|
|| (mCurrent == mSecond && mCurrent->IsDone());
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator:: Last(void)
|
|
{
|
|
nsresult rv;
|
|
nsIBidirectionalEnumerator* be;
|
|
rv = mSecond->QueryInterface(nsIBidirectionalEnumerator::IID(), (void**)&be);
|
|
if (NS_FAILED(rv)) return rv;
|
|
mCurrent = mSecond;
|
|
rv = be->Last();
|
|
NS_RELEASE(be);
|
|
return rv;
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
nsConjoiningEnumerator:: Prev(void)
|
|
{
|
|
nsresult rv;
|
|
nsIBidirectionalEnumerator* be;
|
|
rv = mCurrent->QueryInterface(nsIBidirectionalEnumerator::IID(), (void**)&be);
|
|
if (NS_FAILED(rv)) return rv;
|
|
rv = be->Prev();
|
|
NS_RELEASE(be);
|
|
if (NS_FAILED(rv) && mCurrent == mSecond) {
|
|
rv = mFirst->QueryInterface(nsIBidirectionalEnumerator::IID(), (void**)&be);
|
|
if (NS_FAILED(rv)) return rv;
|
|
mCurrent = mFirst;
|
|
rv = be->Last();
|
|
NS_RELEASE(be);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
NS_COM nsresult
|
|
NS_NewConjoiningEnumerator(nsIEnumerator* first, nsIEnumerator* second,
|
|
nsIBidirectionalEnumerator* *aInstancePtrResult)
|
|
{
|
|
if (aInstancePtrResult == 0)
|
|
return NS_ERROR_NULL_POINTER;
|
|
nsConjoiningEnumerator* e = new nsConjoiningEnumerator(first, second);
|
|
if (e == 0)
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
NS_ADDREF(e);
|
|
*aInstancePtrResult = e;
|
|
return NS_OK;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|