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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 org.eclipse.swt.*;

class PngIdatChunk extends PngChunk {

	static final int HEADER_BYTES_LENGTH = 2;
	static final int ADLER_FIELD_LENGTH = 4;
	static final int HEADER_BYTE1_DATA_OFFSET = DATA_OFFSET + 0;
	static final int HEADER_BYTE2_DATA_OFFSET = DATA_OFFSET + 1;
	static final int ADLER_DATA_OFFSET = DATA_OFFSET + 2; // plus variable compressed data length

PngIdatChunk(byte headerByte1, byte headerByte2, byte[] data, int adler) {
	super(data.length + HEADER_BYTES_LENGTH + ADLER_FIELD_LENGTH);
	setType(TYPE_IDAT);
	reference[HEADER_BYTE1_DATA_OFFSET] = headerByte1;
	reference[HEADER_BYTE2_DATA_OFFSET] = headerByte2;
	System.arraycopy(data, 0, reference, DATA_OFFSET, data.length);
	setInt32(ADLER_DATA_OFFSET, adler);
	setCRC(computeCRC());
}

PngIdatChunk(byte[] reference) {
	super(reference);
}

@Override
int getChunkType() {
	return CHUNK_IDAT;
}

/**
 * Answer whether the chunk is a valid IDAT chunk.
 */
@Override
void validate(PngFileReadState readState, PngIhdrChunk headerChunk) {
	if (!readState.readIHDR
		|| (headerChunk.getMustHavePalette() && !readState.readPLTE)
		|| readState.readIEND)
	{
		SWT.error(SWT.ERROR_INVALID_IMAGE);
	} else {
		readState.readIDAT = true;
	}

	super.validate(readState, headerChunk);
}

byte getDataByteAtOffset(int offset) {
	return reference[DATA_OFFSET + offset];
}

}