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A Java NIO HTTP client/server as light as possible

There is a newer version: 1.0.99

package com.davfx.ninio.http;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.zip.CRC32;
import java.util.zip.Deflater;

import com.davfx.ninio.common.ByteBufferHandler;

final class GzipWriter {
	private static final int BUFFER_SIZE = 4 * 1024;

	private static final int OS_TYPE_UNKNOWN = 0xFF;

	private final ByteBufferHandler handler;
	private boolean gzipHeaderWritten = false;
	private final Deflater deflater = new Deflater(Deflater.DEFAULT_COMPRESSION, true);
	private final CRC32 crc = new CRC32();

	public GzipWriter(ByteBufferHandler handler) {
		this.handler = handler;
	}

	private ByteBuffer buildGzipFooter() {
		ByteBuffer b = ByteBuffer.allocate(8);
		b.order(ByteOrder.LITTLE_ENDIAN);
		b.putInt((int) (crc.getValue() & 0xFFFFFFFFL));
		b.putInt(deflater.getTotalIn());
		b.flip();
		return b;
	}

	private static ByteBuffer buildGzipHeaders() {
		int time = (int) (System.currentTimeMillis() / 1000L);
		ByteBuffer b = ByteBuffer.allocate(10);
		b.order(ByteOrder.LITTLE_ENDIAN);
		b.putShort((short) GzipReader.GZIP_MAGIC);
		b.put((byte) Deflater.DEFLATED);
		b.put((byte) 0);
		b.putInt(time);
		b.put((byte) 0);
		b.put((byte) OS_TYPE_UNKNOWN);
		b.flip();
		return b;
	}

	public void handle(ByteBuffer buffer) {
		deflater.setInput(buffer.array(), buffer.position(), buffer.remaining());
		crc.update(buffer.array(), buffer.position(), buffer.remaining());
		buffer.position(buffer.limit());
		write();
	}

	public void close() {
		deflater.finish();
		write();
		handler.handle(null, buildGzipFooter());
	}

	private void write() {
		if (!gzipHeaderWritten) {
			handler.handle(null, buildGzipHeaders());
			gzipHeaderWritten = true;
		}
		while (true) {
			ByteBuffer deflated = ByteBuffer.allocate(BUFFER_SIZE);
			int c = deflater.deflate(deflated.array(), deflated.position(),
					deflated.remaining());
			if (c <= 0) {
				break;
			}
			deflated.position(deflated.position() + c);
			deflated.flip();
			handler.handle(null, deflated);
		}
	}
}