org.firebirdsql.jdbc

Class FBBlob.FBBlobInputStream

Enclosing Class:
FBBlob
Implemented Interfaces:
FirebirdBlob.BlobInputStream

public class FBBlob.FBBlobInputStream
extends InputStream
implements FirebirdBlob.BlobInputStream

An input stream for reading directly from a FBBlob instance.

Fields inherited from interface org.firebirdsql.jdbc.FirebirdBlob.BlobInputStream

SEEK_MODE_ABSOLUTE, SEEK_MODE_FROM_TAIL, SEEK_MODE_RELATIVE

Method Summary

int
available()
Get number of available bytes that can be read without blocking.
void
close()
Close this stream.
FirebirdBlob
getBlob()
Get instance of FirebirdBlob to which this stream belongs to.
long
length()
Get Blob length.
int
read()
Read single byte from the stream.
int
read(byte[] b, int off, int len)
Read some bytes from the stream without blocking.
void
readFully(byte[] b)
Read buffer.length bytes from the buffer.
void
readFully(byte[] b, int off, int len)
Read length from the stream into the specified buffer.
void
seek(int position)
Move current position in the Blob stream.
void
seek(int position, int seekMode)
Move current position in the Blob stream.

Method Details

available

public int available()
            throws IOException
Get number of available bytes that can be read without blocking. This method will return number of bytes of the last read blob segment in the blob buffer.
Specified by:
available in interface FirebirdBlob.BlobInputStream
Returns:
number of bytes available without blocking or -1 if end of stream is reached.

close

public void close()
            throws IOException
Close this stream.
Specified by:
close in interface FirebirdBlob.BlobInputStream

getBlob

public FirebirdBlob getBlob()
Get instance of FirebirdBlob to which this stream belongs to.

Note, code

 FirebirdBlob.BlobInputStream otherStream = (FirebirdBlob.BlobInputStream)
     inputStream.getBlob().getBinaryStream();
 
will return new stream object.
Specified by:
getBlob in interface FirebirdBlob.BlobInputStream
Returns:
instance of FirebirdBlob.

length

public long length()
            throws IOException
Get Blob length. This is shortcut method for the inputStream.getBlob().length() call, however is more resource friendly, because no new Blob handle is created.
Specified by:
length in interface FirebirdBlob.BlobInputStream
Returns:
length of the blob.

read

public int read()
            throws IOException
Read single byte from the stream.
Specified by:
read in interface FirebirdBlob.BlobInputStream
Returns:
next byte read from the stream or -1 if end of stream was reached.

read

public int read(byte[] b,
                int off,
                int len)
            throws IOException
Read some bytes from the stream without blocking.
Specified by:
read in interface FirebirdBlob.BlobInputStream
Parameters:
Returns:
number of bytes that were read.

readFully

public void readFully(byte[] b)
            throws IOException
Read buffer.length bytes from the buffer. This is a shortcut method for readFully(buffer, 0, buffer.length) call.
Specified by:
readFully in interface FirebirdBlob.BlobInputStream
Parameters:

readFully

public void readFully(byte[] b,
                      int off,
                      int len)
            throws IOException
Read length from the stream into the specified buffer. This method can block until desired number of bytes is read, it can throw an exception if end of stream was reached during read.
Specified by:
readFully in interface FirebirdBlob.BlobInputStream
Parameters:

seek

public void seek(int position)
            throws IOException
Specified by:
seek in interface FirebirdBlob.BlobInputStream
Parameters:
position - absolute position to seek, starting position is 0 (note, in Blob.getBytes(long, int) starting position is 1).

seek

public void seek(int position,
                 int seekMode)
            throws IOException
Move current position in the Blob stream. Depending on the specified seek mode, position can be either positive or negative.

Note, this method allows to move position in the Blob stream only forward. If you need to read data before the current position, new stream must be opened.

Specified by:
seek in interface FirebirdBlob.BlobInputStream
Parameters:
position - position in the stream, starting position is 0 (note, in Blob.getBytes(long, int) starting position is 1).
seekMode - mode of seek operation, one of FirebirdBlob.BlobInputStream.SEEK_MODE_ABSOLUTE, FirebirdBlob.BlobInputStream.SEEK_MODE_RELATIVE or FirebirdBlob.BlobInputStream.SEEK_MODE_FROM_TAIL.

Copyright B) 2001 David Jencks and other authors. All rights reserved.