org.apache.derby.iapi.types
Interface PositionedStream

All Known Implementing Classes:
LOBInputStream, PositionedStoreStream

public interface PositionedStream

This interface describes a stream that is aware of its own position and can reposition itself on request.

This interface doesn't convey any information about how expensive it is for the stream to reposition itself.


Method Summary
 java.io.InputStream asInputStream()
          Returns a reference to self as an InputStream.
 long getPosition()
          Returns the current byte position of the stream.
 void reposition(long requestedPos)
          Repositions the stream to the requested byte position.
 

Method Detail

asInputStream

java.io.InputStream asInputStream()
Returns a reference to self as an InputStream.

This method is not allowed to return null.

Returns:
An InputStream reference to self.

getPosition

long getPosition()
Returns the current byte position of the stream.

Returns:
Current byte position of the stream.

reposition

void reposition(long requestedPos)
                throws java.io.IOException,
                       StandardException
Repositions the stream to the requested byte position.

If the repositioning fails because the stream is exhausted, most likely because of an invalid position specified by the user, the stream is reset to position zero and an EOFException is thrown.

Parameters:
requestedPos - requested byte position, first position is 0
Throws:
java.io.IOException - if accessing the stream fails
EOFException - if the requested position is equal to or larger than the length of the stream
StandardException - if an error occurs in store

Built on Thu 2011-03-10 11:54:14+0000, from revision ???

Apache Derby V10.6 Internals - Copyright © 2004,2007 The Apache Software Foundation. All Rights Reserved.