http://www.jboss.org/xnio: The API JAR of the XNIO project (JBoss by Red Hat) 
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 * Copyright 2008 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed 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
 *
 *     http://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 org.xnio.channels;

import java.nio.ByteBuffer;
import java.nio.channels.ScatteringByteChannel;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.FileChannel;
import java.io.IOException;
import org.xnio.ChannelListener;


A stream source channel.  This type of channel is a readable source for bytes.  While all channel types are
thread-safe, reading a stream from more than one thread concurrently will cause data corruption and may be
disallowed at the option of the implementation.

/**
 * A stream source channel.  This type of channel is a readable source for bytes.  While all channel types are
  * thread-safe, reading a stream from more than one thread concurrently will cause data corruption and may be
  * disallowed at the option of the implementation.
 */
public interface StreamSourceChannel extends ReadableByteChannel, ScatteringByteChannel, SuspendableReadChannel {

    
Transfers bytes into the given file from this channel. Using this method in preference to FileChannel.transferFrom(ReadableByteChannel, long, long) may provide a performance advantage on some platforms. 
 If the current thread is interrupted when this method is called, it may throw a InterruptedIOException; however, if this exception is thrown, the InterruptedIOException.bytesTransferred field is guaranteed to be 0. 
Params:
  • position – the position within the file from which the transfer is to begin
  • count – the number of bytes to be transferred
  • target – the file to write to
Throws:
Returns:the number of bytes (possibly 0) that were actually transferred
/**
     * Transfers bytes into the given file from this channel.  Using this method in preference to {@link FileChannel#transferFrom(ReadableByteChannel, long, long)}
     * may provide a performance advantage on some platforms.
     * <p>
     * If the current thread is interrupted when this method is called, it may throw a {@link java.io.InterruptedIOException};
     * however, if this exception is thrown, the {@link java.io.InterruptedIOException#bytesTransferred} field is
     * guaranteed to be 0.
     *
     * @param position the position within the file from which the transfer is to begin
     * @param count the number of bytes to be transferred
     * @param target the file to write to
     * @return the number of bytes (possibly 0) that were actually transferred
     * @throws IOException if an I/O error occurs
     */
    long transferTo(long position, long count, FileChannel target) throws IOException;

    
Transfers bytes into the given channel target. On some platforms, this may avoid copying bytes between user and kernel space. On other platforms, bytes are passed through the throughBuffer parameter's buffer space. On entry, throughBuffer will be cleared. On exit, the buffer will be flipped for emptying, and may possibly be empty or may contain data. If this method returns a value less than count, then the remaining data in throughBuffer may contain data read from this channel which must be written to target to complete the operation. Note that using a direct buffer may provide an intermediate performance gain on platforms without zero-copy facilities. 
 If the current thread is interrupted when this method is called, it may throw a InterruptedIOException; however, if this exception is thrown, the InterruptedIOException.bytesTransferred field is guaranteed to be 0. Note that the return value is the amount of data that was actually transferred to the StreamSinkChannel. The actual amount of data read could be larger than this, and can be calculated by adding the return value and the amount of data left in throughBuffer. 
Params:
  • count – the number of bytes to be transferred
  • throughBuffer – the buffer to copy through.
  • target – the destination to write to
Throws:
Returns:the number of bytes (possibly 0) that were actually transferred, or -1 if the end of input was reached
/**
     * Transfers bytes into the given channel target.  On some platforms, this may avoid copying bytes between user
     * and kernel space.  On other platforms, bytes are passed through the {@code throughBuffer} parameter's buffer
     * space.  On entry, {@code throughBuffer} will be cleared.  On exit, the buffer will be
     * flipped for emptying, and may possibly be empty or may contain data.  If this method returns a value less than
     * {@code count}, then the remaining data in {@code throughBuffer} may contain data read from this channel which must
     * be written to {@code target} to complete the operation.  Note that using a direct buffer may provide an
     * intermediate performance gain on platforms without zero-copy facilities.
     * <p>
     * If the current thread is interrupted when this method is called, it may throw a {@link java.io.InterruptedIOException};
     * however, if this exception is thrown, the {@link java.io.InterruptedIOException#bytesTransferred} field is
     * guaranteed to be 0.
     *
     * Note that the return value is the amount of data that was actually transferred to the {@link StreamSinkChannel}.
     * The actual amount of data read could be larger than this, and can be calculated by adding the return value and
     * the amount of data left in {@code throughBuffer}.
     *
     * @param count the number of bytes to be transferred
     * @param throughBuffer the buffer to copy through.
     * @param target the destination to write to
     * @return the number of bytes (possibly 0) that were actually transferred, or -1 if the end of input was reached
     * @throws IOException if an I/O error occurs
     */
    long transferTo(long count, ByteBuffer throughBuffer, StreamSinkChannel target) throws IOException;

    
{@inheritDoc} 
/** {@inheritDoc} */
    ChannelListener.Setter<? extends StreamSourceChannel> getReadSetter();

    
{@inheritDoc} 
/** {@inheritDoc} */
    ChannelListener.Setter<? extends StreamSourceChannel> getCloseSetter();
}