Java tutorial
/** * This file is part of Waarp Project. * * Copyright 2009, Frederic Bregier, and individual contributors by the @author tags. See the * COPYRIGHT.txt in the distribution for a full listing of individual contributors. * * All Waarp Project is free software: you can redistribute it and/or modify it under the terms of * the GNU General Public License as published by the Free Software Foundation, either version 3 of * the License, or (at your option) any later version. * * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General * Public License for more details. * * You should have received a copy of the GNU General Public License along with Waarp . If not, see * <http://www.gnu.org/licenses/>. */ package org.waarp.common.file; import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBufHolder; import io.netty.channel.FileRegion; import io.netty.channel.MessageSizeEstimator; /** * DataBlock size estimator * * @author Frederic Bregier * */ public class DataBlockSizeEstimator implements MessageSizeEstimator { private final Handle handle; /** * */ public DataBlockSizeEstimator() { handle = new HandleImpl(); } private static final class HandleImpl implements Handle { private HandleImpl() { } @Override public int size(Object msg) { if (!(msg instanceof DataBlock)) { // Type unimplemented if (msg instanceof ByteBuf) { return ((ByteBuf) msg).readableBytes(); } if (msg instanceof ByteBufHolder) { return ((ByteBufHolder) msg).content().readableBytes(); } if (msg instanceof FileRegion) { return 0; } } DataBlock dataBlock = (DataBlock) msg; return dataBlock.getByteCount(); } } @Override public Handle newHandle() { return handle; } }