/******************************************************************************* * Copyright (c) 2000, 2003 IBM Corporation and others. * All rights reserved. This program and the accompanying materials  * are made available under the terms of the Common Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/cpl-v10.html *  * Contributors: *     IBM Corporation - initial API and implementation *******************************************************************************/package org.eclipse.swt.internal.image;import java.io.*;final class TIFFRandomFileAccess {	LEDataInputStream inputStream;	int start, current, next;	byte[][] buffers;	static final int CHUNK_SIZE = 8192;	static final int LIST_SIZE = 128;public TIFFRandomFileAccess(LEDataInputStream stream) {	inputStream = stream;	start = current = next = inputStream.getPosition();	buffers = new byte[LIST_SIZE][];}void seek(int pos) throws IOException {	if (pos == current) return;	if (pos < start) throw new IOException();	current = pos;		if (current > next) {		int n = current - next;		/* store required bytes */		int index = next / CHUNK_SIZE;		int offset = next % CHUNK_SIZE;		while (n > 0) {			if (index >= buffers.length) {				byte[][] oldBuffers = buffers;				buffers = new byte[Math.max(index + 1, oldBuffers.length + LIST_SIZE)][];				System.arraycopy(oldBuffers, 0, buffers, 0, oldBuffers.length);			}			if (buffers[index] == null) buffers[index] = new byte[CHUNK_SIZE];			int cnt = inputStream.read(buffers[index], offset, Math.min(n, CHUNK_SIZE - offset));			n -= cnt;			next += cnt;			index++;			offset = 0;		}	}}void read(byte b[]) throws IOException {	int size = b.length;	int nCached = Math.min(size, next - current);	int nMissing = size - next + current;	int destNext = 0;	if (nCached > 0) {		/* Get cached bytes */		int index = current / CHUNK_SIZE;		int offset = current % CHUNK_SIZE;				while (nCached > 0) {			int cnt = Math.min(nCached, CHUNK_SIZE - offset);			System.arraycopy(buffers[index], offset, b, destNext, cnt);			nCached -= cnt; 			destNext += cnt;			index++;			offset = 0;		}	}	if (nMissing > 0) {		/* Read required bytes */		int index = next / CHUNK_SIZE;		int offset = next % CHUNK_SIZE;		while (nMissing > 0) {			if (index >= buffers.length) {				byte[][] oldBuffers = buffers;				buffers = new byte[Math.max(index, oldBuffers.length + LIST_SIZE)][];				System.arraycopy(oldBuffers, 0, buffers, 0, oldBuffers.length);			}			if (buffers[index] == null) buffers[index] = new byte[CHUNK_SIZE];			int cnt = inputStream.read(buffers[index], offset, Math.min(nMissing, CHUNK_SIZE - offset));			System.arraycopy(buffers[index], offset, b, destNext, cnt);			nMissing -= cnt;			next += cnt;			destNext += cnt;			index++;			offset = 0;		}	}	current += size;}}