/*
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* to you under the Apache License, Version 2.0 (the
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* http://www.apache.org/licenses/LICENSE-2.0
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*
* This software consists of voluntary contributions made by many
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*
* This decoder is optimized to transfer data directly from the underlying * I/O session's channel to a {@link FileChannel}, whenever * possible avoiding intermediate buffering in the session buffer. * * @since 4.0 */ public class IdentityDecoder extends AbstractContentDecoder implements FileContentDecoder { public IdentityDecoder( final ReadableByteChannel channel, final SessionInputBuffer buffer, final BasicHttpTransportMetrics metrics) { super(channel, buffer, metrics); } /** * Sets the completed status of this decoder. Normally this is not necessary * (the decoder will automatically complete when the underlying channel * returns EOF). It is useful to mark the decoder as completed if you have * some other means to know all the necessary data has been read and want to * reuse the underlying connection for more messages. */ public void setCompleted(final boolean completed) { this.completed = completed; } @Override public int read(final ByteBuffer dst) throws IOException { Args.notNull(dst, "Byte buffer"); if (this.completed) { return -1; } final int bytesRead; if (this.buffer.hasData()) { bytesRead = this.buffer.read(dst); } else { bytesRead = readFromChannel(dst); } if (bytesRead == -1) { this.completed = true; } return bytesRead; } @Override public long transfer( final FileChannel dst, final long position, final long count) throws IOException { if (dst == null) { return 0; } if (this.completed) { return 0; } long bytesRead; if (this.buffer.hasData()) { dst.position(position); bytesRead = this.buffer.read(dst); } else { if (this.channel.isOpen()) { if (position > dst.size()) { throw new IOException("Position past end of file [" + position + " > " + dst.size() + "]"); } bytesRead = dst.transferFrom(this.channel, position, count); if (count > 0 && bytesRead == 0) { bytesRead = this.buffer.fill(this.channel); } } else { bytesRead = -1; } if (bytesRead > 0) { this.metrics.incrementBytesTransferred(bytesRead); } } if (bytesRead == -1) { this.completed = true; } return bytesRead; } @Override public String toString() { final StringBuilder sb = new StringBuilder(); sb.append("[identity; completed: "); sb.append(this.completed); sb.append("]"); return sb.toString(); } }