/*
* CVS Identifier:
*
* $Id: RandomAccessIO.java,v 1.15 2001/10/24 12:07:02 grosbois Exp $
*
* Interface:           RandomAccessIO.java
*
* Description:         Interface definition for random access I/O.
*
*
*
* COPYRIGHT:
* 
* This software module was originally developed by Raphaël Grosbois and
* Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel
* Askelöf (Ericsson Radio Systems AB); and Bertrand Berthelot, David
* Bouchard, Félix Henry, Gerard Mozelle and Patrice Onno (Canon Research
* Centre France S.A) in the course of development of the JPEG2000
* standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This
* software module is an implementation of a part of the JPEG 2000
* Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio
* Systems AB and Canon Research Centre France S.A (collectively JJ2000
* Partners) agree not to assert against ISO/IEC and users of the JPEG
* 2000 Standard (Users) any of their rights under the copyright, not
* including other intellectual property rights, for this software module
* with respect to the usage by ISO/IEC and Users of this software module
* or modifications thereof for use in hardware or software products
* claiming conformance to the JPEG 2000 Standard. Those intending to use
* this software module in hardware or software products are advised that
* their use may infringe existing patents. The original developers of
* this software module, JJ2000 Partners and ISO/IEC assume no liability
* for use of this software module or modifications thereof. No license
* or right to this software module is granted for non JPEG 2000 Standard
* conforming products. JJ2000 Partners have full right to use this
* software module for his/her own purpose, assign or donate this
* software module to any third party and to inhibit third parties from
* using this software module for non JPEG 2000 Standard conforming
* products. This copyright notice must be included in all copies or
* derivative works of this software module.
* 
* Copyright (c) 1999/2000 JJ2000 Partners.
* */
using System;
namespace CSJ2K.j2k.io
{
	
	/// <summary> This abstract class defines the interface to perform random access I/O. It
	/// implements the <tt>BinaryDataInput</tt> and <tt>BinaryDataOutput</tt>
	/// interfaces so that binary data input/output can be performed.
	/// 
	/// <p>This interface supports streams of up to 2 GB in length.</p>
	/// 
	/// </summary>
	/// <seealso cref="BinaryDataInput">
	/// </seealso>
	/// <seealso cref="BinaryDataOutput">
	/// 
	/// </seealso>
	public interface RandomAccessIO:BinaryDataInput, BinaryDataOutput
	{
		/// <summary> Returns the current position in the stream, which is the position from
		/// where the next byte of data would be read. The first byte in the stream
		/// is in position <tt>0</tt>.
		/// 
		/// </summary>
		/// <returns> The offset of the current position, in bytes.
		/// 
		/// </returns>
		/// <exception cref="IOException">If an I/O error ocurred.
		/// 
		/// </exception>
		int Pos
		{
			get;
			
		}
		
		/// <summary> Closes the I/O stream. Prior to closing the stream, any buffered data
		/// (at the bit and byte level) should be written.
		/// 
		/// </summary>
		/// <exception cref="IOException">If an I/O error ocurred. 
		/// 
		/// </exception>
		void  close();
		
		/// <summary> Returns the current length of the stream, in bytes, taking into account
		/// any buffering.
		/// 
		/// </summary>
		/// <returns> The length of the stream, in bytes.
		/// 
		/// </returns>
		/// <exception cref="IOException">If an I/O error ocurred. 
		/// 
		/// </exception>
		int length();
		
		/// <summary> Moves the current position for the next read or write operation to
		/// offset. The offset is measured from the beginning of the stream. The
		/// offset may be set beyond the end of the file, if in write mode. Setting
		/// the offset beyond the end of the file does not change the file
		/// length. The file length will change only by writing after the offset
		/// has been set beyond the end of the file.
		/// 
		/// </summary>
		/// <param name="off">The offset where to move to.
		/// 
		/// </param>
		/// <exception cref="EOFException">If in read-only and seeking beyond EOF.
		/// 
		/// </exception>
		/// <exception cref="IOException">If an I/O error ocurred.
		/// 
		/// </exception>
		void  seek(int off);
		
		/// <summary> Reads a byte of data from the stream. Prior to reading, the stream is
		/// realigned at the byte level.
		/// 
		/// </summary>
		/// <returns> The byte read, as an int.
		/// 
		/// </returns>
		/// <exception cref="EOFException">If the end-of file was reached.
		/// 
		/// </exception>
		/// <exception cref="IOException">If an I/O error ocurred.
		/// 
		/// </exception>
		byte read();
		
		/// <summary> Reads up to len bytes of data from this file into an array of
		/// bytes. This method reads repeatedly from the stream until all the bytes
		/// are read. This method blocks until all the bytes are read, the end of
		/// the stream is detected, or an exception is thrown.
		/// 
		/// </summary>
		/// <param name="b">The buffer into which the data is to be read. It must be long
		/// enough.
		/// 
		/// </param>
		/// <param name="off">The index in 'b' where to place the first byte read.
		/// 
		/// </param>
		/// <param name="len">The number of bytes to read.
		/// 
		/// </param>
		/// <exception cref="EOFException">If the end-of file was reached before
		/// getting all the necessary data.
		/// 
		/// </exception>
		/// <exception cref="IOException">If an I/O error ocurred.
		/// 
		/// </exception>
		void  readFully(byte[] b, int off, int len);
		
		/// <summary> Writes a byte to the stream. Prior to writing, the stream is realigned
		/// at the byte level.
		/// 
		/// </summary>
		/// <param name="b">The byte to write. The lower 8 bits of <tt>b</tt> are
		/// written.
		/// 
		/// </param>
		/// <exception cref="IOException">If an I/O error ocurred. 
		/// 
		/// </exception>
		void  write(byte b);
	}
}