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The osx x86_64 swt jar as available in the Eclipse 4.6 (Neon) release for OSX. It is suitable for use with jface and other dependencies available from maven central in the org.eclipse.scout.sdk.deps group. The sources is copied from swt-4.6-cocoa-macosx-x86_64.zip from http://download.eclipse.org/eclipse/downloads/drops4/R-4.6-201606061100/ and javadoc is generated from sources.

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/*******************************************************************************
 * Copyright (c) 2000, 2011 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.internal.image;


import java.io.*;

import org.eclipse.swt.*;

public class PngDecodingDataStream extends InputStream {
	InputStream stream;
	byte currentByte;
	int nextBitIndex;

	PngLzBlockReader lzBlockReader;
	int adlerValue;

	static final int PRIME = 65521;
	static final int MAX_BIT = 7;

PngDecodingDataStream(InputStream stream) throws IOException {
	super();
	this.stream = stream;
	nextBitIndex = MAX_BIT + 1;
	adlerValue = 1;
	lzBlockReader = new PngLzBlockReader(this);
	readCompressedDataHeader();
	lzBlockReader.readNextBlockHeader();
}

/**
 * This method should be called when the image decoder thinks
 * that all of the compressed image data has been read. This
 * method will ensure that the next data value is an end of
 * block marker. If there are more blocks after this one,
 * the method will read them and ensure that they are empty.
 */
void assertImageDataAtEnd() throws IOException {
	lzBlockReader.assertCompressedDataAtEnd();
}

@Override
public void close() throws IOException {
	assertImageDataAtEnd();
	checkAdler();
}

int getNextIdatBits(int length) throws IOException {
	int value = 0;
	for (int i = 0; i < length; i++) {
		value |= (getNextIdatBit() << i);
	}
	return value;
}

int getNextIdatBit() throws IOException {
	if (nextBitIndex > MAX_BIT) {
		currentByte = getNextIdatByte();
		nextBitIndex = 0;
	}
	return (currentByte & (1 << nextBitIndex)) >> nextBitIndex++;
}

byte getNextIdatByte() throws IOException {
	byte nextByte = (byte)stream.read();
	nextBitIndex = MAX_BIT + 1;
	return nextByte;
}

void updateAdler(byte value) {
	int low = adlerValue & 0xFFFF;
	int high = (adlerValue >> 16) & 0xFFFF;
	int valueInt = value & 0xFF;
	low = (low + valueInt) % PRIME;
	high = (low + high) % PRIME;
	adlerValue = (high << 16) | low;
}

@Override
public int read() throws IOException {
	byte nextDecodedByte = lzBlockReader.getNextByte();
	updateAdler(nextDecodedByte);
	return nextDecodedByte & 0xFF;
}

@Override
public int read(byte[] buffer, int off, int len) throws IOException {
	for (int i = 0; i < len; i++) {
		int b = read();
		if (b == -1) return i;
		buffer[off + i] = (byte)b;
	}
	return len;
}

void error() {
	SWT.error(SWT.ERROR_INVALID_IMAGE);
}

private void readCompressedDataHeader() throws IOException {
	byte headerByte1 = getNextIdatByte();
	byte headerByte2 = getNextIdatByte();

	int number = ((headerByte1 & 0xFF) << 8) | (headerByte2 & 0xFF);
	if (number % 31 != 0) error();

	int compressionMethod = headerByte1 & 0x0F;
	if (compressionMethod != 8) error();

	int windowSizeHint = (headerByte1 & 0xF0) >> 4;
	if (windowSizeHint > 7) error();
	int windowSize = (1 << (windowSizeHint + 8));
	lzBlockReader.setWindowSize(windowSize);

	int dictionary = (headerByte2 & (1 << 5));
	if (dictionary != 0) error();

//	int compressionLevel = (headerByte2 & 0xC0) >> 6;
}

void checkAdler() throws IOException {
	int storedAdler = ((getNextIdatByte() & 0xFF) << 24)
		| ((getNextIdatByte() & 0xFF) << 16)
		| ((getNextIdatByte() & 0xFF) << 8)
		| (getNextIdatByte() & 0xFF);
	if (storedAdler != adlerValue) error();
}

}