Stream Class

You use a Stream to read or write streamed data (usually LONG).

  • A read-able Stream is used to obtain streamed data from a result set or OUT bind variable from a stored procedure call. A read-able Stream must be read completely until the end of data is reached or it should be closed to discard any unwanted data.

  • A write-able Stream is used to provide streamed data (usually LONG) to parameterized statements including callable statements.

Table 13-44 Enumerated Values Used by Stream Class

Attribute Options
Status
  • READY_FOR_READ indicates that the Stream is ready for read operations

  • READY_FOR_WRITE indicates that the Stream is ready for write operations

  • INACTIVE indicates that the Stream is not available for ready or write operations


Table 13-45 Summary of Stream Methods

Method Summary

readBuffer()

Reads the stream and returns the amount of data read from the Stream object.

readLastBuffer()

Reads last buffer from Stream.

writeBuffer()

Writes data from buffer to the stream.

writeLastBuffer()

Writes the last data from buffer to the stream.

status()

Returns the current status of the stream.



readBuffer()

Reads data from Stream. The size parameter specifies the maximum number of byte characters to read. Returns the amount of data read from the Stream object. -1 means end of data on the stream.

Syntax

virtual int readBuffer(
   char *buffer,
   unsigned int size) = 0;
Parameter Description
buffer
Pointer to data buffer; must be allocated and freed by caller.
size
Specifies the number of bytes to be read.


readLastBuffer()

Reads the last buffer from the Stream. It can also be called top discard unread data. The size parameter specifies the maximum number of byte characters to read. Returns the amount of data read from the Stream object; -1 means end of data on the stream.

Syntax

virtual int readLastBuffer(
   char *buffer,
   unsigned int size) = 0;
Parameter Description
buffer
Pointer to data buffer; must be allocated and freed by caller.
size
Specifies the number of bytes to be read.


writeBuffer()

Writes data from buffer to the stream. The amount of data is determined by size.

Syntax

virtual void writeBuffer(
   char *buffer,
   unsigned int size) = 0;
Parameter Description
buffer
Pointer to data buffer.
size
Specifies the number of chars to be written.


writeLastBuffer()

This method writes the last data buffer to the stream. It can also be called to write the last chunk of data. The amount of data written is determined by size.

Syntax

virtual void writeLastBuffer(
   char *buffer,
   unsigned int size) = 0;
Parameter Description
buffer
Pointer to data buffer.
size
Specifies the number of bytes to be written.


status()

Returns the current Status, as defined in Table 13-44 .

Syntax

virtual Status status() const;