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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.channel;

import io.netty.util.ReferenceCounted;

import java.io.IOException;
import java.nio.channels.FileChannel;
import java.nio.channels.WritableByteChannel;

/**
 * A region of a file that is sent via a {@link Channel} which supports
 * zero-copy file transfer.
 *
 * Upgrade your JDK / JRE
 *
 * {@link FileChannel#transferTo(long, long, WritableByteChannel)} has at least
 * four known bugs in the old versions of Sun JDK and perhaps its derived ones.
 * Please upgrade your JDK to 1.6.0_18 or later version if you are going to use
 * zero-copy file transfer.
 * 
 * 5103988
 *   - FileChannel.transferTo() should return -1 for EAGAIN instead throws IOException
 * 6253145
 *   - FileChannel.transferTo() on Linux fails when going beyond 2GB boundary
 * 6427312
 *   - FileChannel.transferTo() throws IOException "system call interrupted"
 * 6470086
 *   - FileChannel.transferTo(2147483647, 1, channel) causes "Value too large" exception
 * 
 *
 * Check your operating system and JDK / JRE
 *
 * If your operating system (or JDK / JRE) does not support zero-copy file
 * transfer, sending a file with {@link FileRegion} might fail or yield worse
 * performance.  For example, sending a large file doesn't work well in Windows.
 *
 * Not all transports support it
 */
public interface FileRegion extends ReferenceCounted {

    /**
     * Returns the offset in the file where the transfer began.
     */
    long position();

    /**
     * Returns the bytes which was transferred already.
     *
     * @deprecated Use {@link #transferred()} instead.
     */
    @Deprecated
    long transfered();

    /**
     * Returns the bytes which was transferred already.
     */
    long transferred();

    /**
     * Returns the number of bytes to transfer.
     */
    long count();

    /**
     * Transfers the content of this file region to the specified channel.
     *
     * @param target    the destination of the transfer
     * @param position  the relative offset of the file where the transfer
     *                  begins from.  For example, 0 will make the
     *                  transfer start from {@link #position()}th byte and
     *                  {@link #count()} - 1 will make the last
     *                  byte of the region transferred.
     */
    long transferTo(WritableByteChannel target, long position) throws IOException;

    @Override
    FileRegion retain();

    @Override
    FileRegion retain(int increment);

    @Override
    FileRegion touch();

    @Override
    FileRegion touch(Object hint);
}