DcmOutputStream Class Reference

base class for output streams. More...

Inheritance diagram for DcmOutputStream:

DcmOutputBufferStream DcmOutputFileStream List of all members.

Public Member Functions

virtual ~DcmOutputStream ()
 destructor
virtual OFBool good () const
 returns the status of the stream.
virtual OFCondition status () const
 returns the status of the consumer as an OFCondition object.
virtual OFBool isFlushed () const
 returns true if the stream is flushed, i.e.
virtual Uint32 avail () const
 returns the minimum number of bytes that can be written with the next call to write().
virtual Uint32 write (const void *buf, Uint32 buflen)
 processes as many bytes as possible from the given input block.
virtual void flush ()
 instructs the stream to flush its internal content until either the stream becomes "flushed" or I/O suspension occurs.
virtual Uint32 tell () const
 returns the total number of bytes written to the stream so far
virtual OFCondition installCompressionFilter (E_StreamCompression filterType)
 installs a compression filter for the given stream compression type, which should be neither ESC_none nor ESC_unsupported.

Protected Member Functions

 DcmOutputStream (DcmConsumer *initial)
 protected constructor, to be called from derived class constructor

Private Member Functions

 DcmOutputStream (const DcmOutputStream &)
 private unimplemented copy constructor
DcmOutputStream & operator= (const DcmOutputStream &)
 private unimplemented copy assignment operator

Private Attributes

DcmConsumer * current_
 pointer to first node in filter chain
DcmOutputFilter * compressionFilter_
 pointer to compression filter, NULL if no compression
Uint32 tell_
 counter for number of bytes written so far

Detailed Description

base class for output streams.

This class cannot be instantiated since the constructor is protected.

Definition at line 124 of file dcostrma.h.

Constructor & Destructor Documentation

DcmOutputStream::DcmOutputStream (  DcmConsumer *  initial  )  [protected]
 

protected constructor, to be called from derived class constructor

Parameters:
initial initial pointer to first node in filter chain The pointer is not dereferenced in the constructor, so the object pointed to may be initialized later in the subclass constructor.

Member Function Documentation

virtual Uint32 DcmOutputStream::avail (   )  const [virtual]
 

returns the minimum number of bytes that can be written with the next call to write().

The DcmObject write methods rely on avail to return a value > 0 if there is no I/O suspension since certain data such as tag and length are only written "en bloc", i.e. all or nothing.

Returns:
minimum of space available in stream

virtual void DcmOutputStream::flush (   )  [virtual]
 

instructs the stream to flush its internal content until either the stream becomes "flushed" or I/O suspension occurs.

After a call to flush(), a call to write() will produce undefined behaviour.

virtual OFBool DcmOutputStream::good (   )  const [virtual]
 

returns the status of the stream.

Unless the status is good, the stream will not permit any operation.

Returns:
status, true if good

virtual OFCondition DcmOutputStream::installCompressionFilter (  E_StreamCompression  filterType  )  [virtual]
 

installs a compression filter for the given stream compression type, which should be neither ESC_none nor ESC_unsupported.

Once a compression filter is active, it cannot be deactivated or replaced during the lifetime of the stream.

Parameters:
filterType type of compression filter
Returns:
EC_Normal if successful, an error code otherwise

virtual OFBool DcmOutputStream::isFlushed (   )  const [virtual]
 

returns true if the stream is flushed, i.e.

has no more data pending in it's internal state that needs to be flushed before the stream is closed.

Returns:
true if stream is flushed, false otherwise

virtual OFCondition DcmOutputStream::status (   )  const [virtual]
 

returns the status of the consumer as an OFCondition object.

Unless the status is good, the consumer will not permit any operation.

Returns:
status, EC_Normal if good

virtual Uint32 DcmOutputStream::tell (   )  const [virtual]
 

returns the total number of bytes written to the stream so far

Returns:
total number of bytes written to the stream

virtual Uint32 DcmOutputStream::write (  const void *  buf,
Uint32  buflen
)  [virtual]
 

processes as many bytes as possible from the given input block.

Parameters:
buf pointer to memory block, must not be NULL
buflen length of memory block
Returns:
number of bytes actually processed.

The documentation for this class was generated from the following file:

Generated on 20 Dec 2005 for OFFIS DCMTK Version 3.5.4 by Doxygen 1.4.5