tikhomirov@534: /*
tikhomirov@534:  * Copyright (c) 2013 TMate Software Ltd
tikhomirov@534:  *  
tikhomirov@534:  * This program is free software; you can redistribute it and/or modify
tikhomirov@534:  * it under the terms of the GNU General Public License as published by
tikhomirov@534:  * the Free Software Foundation; version 2 of the License.
tikhomirov@534:  *
tikhomirov@534:  * This program is distributed in the hope that it will be useful,
tikhomirov@534:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@534:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@534:  * GNU General Public License for more details.
tikhomirov@534:  *
tikhomirov@534:  * For information on how to redistribute this software under
tikhomirov@534:  * the terms of a license other than GNU General Public License
tikhomirov@534:  * contact TMate Software at support@hg4j.com
tikhomirov@534:  */
tikhomirov@534: package org.tmatesoft.hg.internal;
tikhomirov@534: 
tikhomirov@534: import java.io.IOException;
tikhomirov@534: import java.util.zip.Deflater;
tikhomirov@534: import java.util.zip.DeflaterOutputStream;
tikhomirov@534: 
tikhomirov@534: /**
tikhomirov@534:  * {@link DeflaterOutputStream} counterpart for {@link DataSerializer} API
tikhomirov@534:  * 
tikhomirov@534:  * @author Artem Tikhomirov
tikhomirov@534:  * @author TMate Software Ltd.
tikhomirov@534:  */
tikhomirov@534: class DeflaterDataSerializer extends DataSerializer {
tikhomirov@534: 	
tikhomirov@534: 	private static final int AUX_BUFFER_CAPACITY = 5; // room for 5 ints
tikhomirov@534: 
tikhomirov@534: 	private final DataSerializer delegate;
tikhomirov@534: 	private final Deflater deflater;
tikhomirov@534: 	private final byte[] deflateOutBuffer;
tikhomirov@534: 	private final byte[] auxBuffer;
tikhomirov@534: 
tikhomirov@534: 	public DeflaterDataSerializer(DataSerializer delegateSerializer, Deflater def, int bufferSizeHint) {
tikhomirov@534: 		delegate = delegateSerializer;
tikhomirov@534: 		deflater = def;
tikhomirov@534: 		deflateOutBuffer = new byte[bufferSizeHint <= 0 ? 2048 : bufferSizeHint];
tikhomirov@534: 		auxBuffer = new byte[4 * AUX_BUFFER_CAPACITY]; // sizeof(int) * capacity
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	@Override
tikhomirov@534: 	public void writeInt(int... values) throws IOException {
tikhomirov@534: 		for (int i = 0; i < values.length; i+= AUX_BUFFER_CAPACITY) {
tikhomirov@534: 			int idx = 0;
tikhomirov@534: 			for (int j = i, x = Math.min(values.length, i + AUX_BUFFER_CAPACITY); j < x; j++) {
tikhomirov@534: 				int v = values[j];
tikhomirov@534: 				auxBuffer[idx++] = (byte) ((v >>> 24) & 0x0ff);
tikhomirov@534: 				auxBuffer[idx++] = (byte) ((v >>> 16) & 0x0ff);
tikhomirov@534: 				auxBuffer[idx++] = (byte) ((v >>> 8) & 0x0ff);
tikhomirov@534: 				auxBuffer[idx++] = (byte) (v & 0x0ff);
tikhomirov@534: 			}
tikhomirov@534: 			internalWrite(auxBuffer, 0, idx);
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	@Override
tikhomirov@534: 	public void write(byte[] data, int offset, int length) throws IOException {
tikhomirov@534: 		// @see DeflaterOutputStream#write(byte[], int, int)
tikhomirov@534: 		int stride = deflateOutBuffer.length;
tikhomirov@534: 		for (int i = 0; i < length; i += stride) {
tikhomirov@534: 			internalWrite(data, offset + i, Math.min(stride, length - i));
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: 	
tikhomirov@534: 	private void internalWrite(byte[] data, int offset, int length) throws IOException {
tikhomirov@534: 		deflater.setInput(data, offset, length);
tikhomirov@534: 		while (!deflater.needsInput()) {
tikhomirov@534: 			deflate();
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	@Override
tikhomirov@534: 	public void done() {
tikhomirov@534: 		delegate.done();
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	public void finish() throws IOException {
tikhomirov@534: 		if (!deflater.finished()) {
tikhomirov@534: 			deflater.finish();
tikhomirov@534: 			while (!deflater.finished()) {
tikhomirov@534: 				deflate();
tikhomirov@534: 			}
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	protected void deflate() throws IOException {
tikhomirov@534: 		int len = deflater.deflate(deflateOutBuffer, 0, deflateOutBuffer.length);
tikhomirov@534: 		if (len > 0) {
tikhomirov@534: 			delegate.write(deflateOutBuffer, 0, len);
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: }