Re: [問題] 跳出cannot instantiate abstract class

[liptonbin (我還存在耶)]

請問是要實作成 CQueuedPipe::RemoveQHeadFromQueue(){..} 這樣嗎?
還是實作這個即可 CBulkPipe::RemoveQHeadFromQueue(){..}
source code如下

class CBulkPipe : public CQueuedPipe
{
...
protected :
    virtual BOOL RemoveQHeadFromQueue();
    virtual BOOL InsertQHeadToQueue() ;
...
}
class CQueuedPipe : public CPipe
{
public:
    CQueuedPipe(xxx);
    virtual ~CQueuedPipe();
protected:
    virtual BOOL RemoveQHeadFromQueue() = 0;
    virtual BOOL InsertQHeadToQueue() = 0 ;
...
}
BOOL CBulkPipe::RemoveQHeadFromQueue()
{
    ASSERT(m_pPipeQHead);
    return (m_pCEhcd->AsyncDequeueQH( m_pPipeQHead )!=NULL);
}
BOOL CBulkPipe::InsertQHeadToQueue()
{
    ASSERT(m_pPipeQHead);
    return (m_pCEhcd->AsyncQueueQH( m_pPipeQHead )!=NULL);
}


=============================================================================

※ 引述《liptonbin (我還存在耶)》之銘言：
請問我在CreateBulkPipe的return new CBulkPipe(xxx)跳出下面錯誤 請問有人知道是什
麼問題嗎 謝謝
error C2259: 'CBulkPipe' : cannot instantiate abstract class
如下圖,太多參數我就打xxxx

Cpipe.cpp:
CBulkPipe::CBulkPipe(xxxxx)
: CQueuedPipe(xxxx) // constructor for base class
{
    DEBUGMSG( ZONE_PIPE && ZONE_VERBOSE, (TEXT("+CBulkPipe::CBulkPipe\n")) );
    DEBUGCHK( !fIsLowSpeed ); // bulk pipe must be high speed
    DEBUGMSG( ZONE_PIPE && ZONE_VERBOSE, (TEXT("-CBulkPipe::CBulkPipe\n")) );
}
CBulkPipe::~CBulkPipe( )
{
    DEBUGMSG( ZONE_PIPE && ZONE_VERBOSE, (TEXT("+CBulkPipe::~CBulkPipe\n")) );
    ClosePipe();
    DEBUGMSG( ZONE_PIPE && ZONE_VERBOSE, (TEXT("-CBulkPipe::~CBulkPipe\n")) );
}
BOOL CBulkPipe::RemoveQHeadFromQueue()
{
    ASSERT(m_pPipeQHead);
    return (m_pCEhcd->AsyncDequeueQH( m_pPipeQHead )!=NULL);
}
BOOL CBulkPipe::InsertQHeadToQueue()
{
    ASSERT(m_pPipeQHead);
    return (m_pCEhcd->AsyncQueueQH( m_pPipeQHead )!=NULL);
}

CPipeAbs * CreateBulkPipe(xxxx)
{
    return new
CBulkPipe(lpEndpointDescriptor,fIsLowSpeed,fIsHighSpeed,bDeviceAddress,bHubAddress,bHubPort,ttContext,(CEhcd
* const)pChcd);
    //!!!!!這邊跳出錯誤 error C2259: 'CBulkPipe' : cannot instantiate
abstract class
}

----------------------------------------------------------------------------------------------------
class CPipeAbs { // Abstract Pipe class.
public:
    CPipeAbs(UCHAR const
bEndpointAddress):m_bEndpointAddress(bEndpointAddress) {;};
    virtual ~CPipeAbs() {;};
    virtual HCD_REQUEST_STATUS  OpenPipe( void ) = 0;
    virtual HCD_REQUEST_STATUS  ClosePipe( void ) = 0;
    virtual HCD_REQUEST_STATUS  IssueTransfer( xxx)=0;
    virtual HCD_REQUEST_STATUS AbortTransfer( xxx ) = 0;
    virtual HCD_REQUEST_STATUS IsPipeHalted( OUT LPBOOL const lpbHalted )=0;
    virtual void ClearHaltedFlag( void )=0;
    virtual void ResetEndPoint(void) = 0;
    virtual void ChangeMaxPacketSize( IN const USHORT ) {ASSERT(FALSE);};
    virtual BOOL  SetReservedDeviceAddr(UCHAR bReservedDeviceAddr)=0;
    virtual UCHAR GetReservedDeviceAddr()=0;
    UCHAR const m_bEndpointAddress;
};
CPipeAbs * CreateBulkPipe(xxx);
CPipeAbs * CreateControlPipe(xxx);
CPipeAbs * CreateInterruptPipe(xxx);
CPipeAbs * CreateIsochronousPipe(xxx);}

----------------------------------------------------------------------------------------------------------
Cpipe.h:
class CBulkPipe : public CQueuedPipe
{
public:
    CBulkPipe(xxxxx);
    ~CBulkPipe();
    virtual PIPE_TYPE GetType () { return TYPE_BULK; };
    HCD_REQUEST_STATUS  OpenPipe( void );
    HCD_REQUEST_STATUS  ClosePipe( void );
protected :
    virtual BOOL RemoveQHeadFromQueue();
    virtual BOOL InsertQHeadToQueue() ;
private:
    BOOL   AreTransferParametersValid( const STransfer *pTransfer = NULL )
const;
};

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※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 59.124.0.175
→ wangm4a1:CBulkPipe 繼承 CQueuedPipe 有函式沒實作嗎?
--

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※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 27.147.29.81
→ mail6543210:你要init class就要先實作其所有virtual function
※ 編輯: liptonbin       來自: 27.147.29.81         (04/16 22:38)
→ dayyeah:CE EHCI driver?