SocketChannelIOHelper.java

package org.java_websocket;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ByteChannel;

import org.java_websocket.WebSocket.Role;

public class SocketChannelIOHelper {

	/** Returns whether the whole outQueue has been flushed */
	public static boolean batch(WebSocketImpl ws, ByteChannel sockchannel)
			throws IOException {
		ByteBuffer buffer = ws.outQueue.peek();
		WrappedByteChannel c = null;

		if (buffer == null) {
			if (sockchannel instanceof WrappedByteChannel) {
				c = (WrappedByteChannel) sockchannel;
				if (c.isNeedWrite()) {
					c.writeMore();
				}
			}
		} else {
			do {// FIXME writing as much as possible is unfair!!
				/* int written = */sockchannel.write(buffer);
				if (buffer.remaining() > 0) {
					return false;
				} else {
					ws.outQueue.poll(); // Buffer finished. Remove it.
					buffer = ws.outQueue.peek();
				}
			} while (buffer != null);
		}

		if (ws.outQueue.isEmpty() && ws.isFlushAndClose()
				&& ws.getDraft().getRole() == Role.SERVER) {//
			synchronized (ws) {
				ws.closeConnection();
			}
		}
		return c != null ? !((WrappedByteChannel) sockchannel).isNeedWrite()
				: true;
	}

	public static boolean read(final ByteBuffer buf, WebSocketImpl ws,
			ByteChannel channel) throws IOException {
		buf.clear();
		int read = channel.read(buf);
		buf.flip();

		if (read == -1) {
			ws.eot();
			return false;
		}
		return read != 0;
	}

	/**
	 * @see WrappedByteChannel#readMore(ByteBuffer)
	 * @return returns whether there is more data left which can be obtained via
	 *         {@link #readMore(ByteBuffer, WebSocketImpl, WrappedByteChannel)}
	 **/
	public static boolean readMore(final ByteBuffer buf, WebSocketImpl ws,
			WrappedByteChannel channel) throws IOException {
		buf.clear();
		int read = channel.readMore(buf);
		buf.flip();

		if (read == -1) {
			ws.eot();
			return false;
		}
		return channel.isNeedRead();
	}
}