org.xnio.conduits.DeflatingStreamSinkConduit Maven / Gradle / Ivy
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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).
/*
* JBoss, Home of Professional Open Source
*
* Copyright 2013 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.conduits;
import static org.xnio._private.Messages.msg;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.zip.Deflater;
import org.xnio.Buffers;
import org.xnio.channels.StreamSourceChannel;
/**
* A filtering stream sink conduit which compresses the written data.
*
* @author David M. Lloyd
*/
public final class DeflatingStreamSinkConduit extends AbstractStreamSinkConduit implements StreamSinkConduit {
private static final byte[] NO_BYTES = new byte[0];
private final Deflater deflater;
private final ByteBuffer outBuffer;
/**
* Construct a new instance.
*
* @param next the delegate conduit to set
* @param deflater the initialized deflater to use
*/
public DeflatingStreamSinkConduit(final StreamSinkConduit next, final Deflater deflater) {
super(next);
this.deflater = deflater;
outBuffer = ByteBuffer.allocate(16384);
}
public long transferFrom(final FileChannel src, final long position, final long count) throws IOException {
return src.transferTo(position, count, new ConduitWritableByteChannel(this));
}
public long transferFrom(final StreamSourceChannel source, final long count, final ByteBuffer throughBuffer) throws IOException {
return Conduits.transfer(source, count, throughBuffer, this);
}
public int write(final ByteBuffer src) throws IOException {
final ByteBuffer outBuffer = this.outBuffer;
final byte[] outArray = outBuffer.array();
final Deflater deflater = this.deflater;
assert outBuffer.arrayOffset() == 0;
int cnt = 0;
int rem;
int c1, t;
int pos;
while ((rem = src.remaining()) > 0) {
if (! outBuffer.hasRemaining()) {
outBuffer.flip();
try {
if (next.write(outBuffer) == 0) {
return cnt;
}
} finally {
outBuffer.compact();
}
}
pos = src.position();
if (src.hasArray()) {
final byte[] array = src.array();
final int arrayOffset = src.arrayOffset();
deflater.setInput(array, arrayOffset + pos, rem);
c1 = deflater.getTotalIn();
final int dc = deflater.deflate(outArray, outBuffer.position(), outBuffer.remaining());
outBuffer.position(outBuffer.position() + dc);
t = deflater.getTotalIn() - c1;
src.position(pos + t);
cnt += t;
} else {
final byte[] bytes = Buffers.take(src);
deflater.setInput(bytes);
c1 = deflater.getTotalIn();
final int dc = deflater.deflate(outArray, outBuffer.position(), outBuffer.remaining());
outBuffer.position(outBuffer.position() + dc);
t = deflater.getTotalIn() - c1;
src.position(pos + t);
cnt += t;
}
}
return cnt;
}
public long write(final ByteBuffer[] srcs, final int offset, final int length) throws IOException {
final ByteBuffer outBuffer = this.outBuffer;
final byte[] outArray = outBuffer.array();
final Deflater deflater = this.deflater;
assert outBuffer.arrayOffset() == 0;
long cnt = 0;
int rem;
int c1, t;
int pos;
for (int i = 0; i < length; i ++) {
final ByteBuffer src = srcs[i + offset];
while ((rem = src.remaining()) > 0) {
if (! outBuffer.hasRemaining()) {
outBuffer.flip();
try {
if (next.write(outBuffer) == 0) {
return cnt;
}
} finally {
outBuffer.compact();
}
}
pos = src.position();
if (src.hasArray()) {
final byte[] array = src.array();
final int arrayOffset = src.arrayOffset();
deflater.setInput(array, arrayOffset + pos, rem);
c1 = deflater.getTotalIn();
final int dc = deflater.deflate(outArray, outBuffer.position(), outBuffer.remaining());
outBuffer.position(outBuffer.position() + dc);
t = deflater.getTotalIn() - c1;
src.position(pos + t);
cnt += t;
} else {
final byte[] bytes = Buffers.take(src);
deflater.setInput(bytes);
c1 = deflater.getTotalIn();
final int dc = deflater.deflate(outArray, outBuffer.position(), outBuffer.remaining());
outBuffer.position(outBuffer.position() + dc);
t = deflater.getTotalIn() - c1;
src.position(pos + t);
cnt += t;
}
}
}
return cnt;
}
public boolean flush() throws IOException {
final ByteBuffer outBuffer = this.outBuffer;
final byte[] outArray = outBuffer.array();
final Deflater deflater = this.deflater;
assert outBuffer.arrayOffset() == 0;
int res;
int rem;
int pos;
deflater.setInput(NO_BYTES);
for (;;) {
rem = outBuffer.remaining();
pos = outBuffer.position();
res = deflater.deflate(outArray, pos, rem, Deflater.SYNC_FLUSH);
if (pos == 0 && res == rem) {
// hmm, we're stuck (shouldn't be possible)
throw msg.flushSmallBuffer();
} else {
if (res > 0) {
outBuffer.flip();
try {
if (next.write(outBuffer) == 0) {
return false;
}
} finally {
outBuffer.compact();
}
} else if (deflater.needsInput() && pos == 0) {
if (deflater.finished()) {
// idempotent
next.terminateWrites();
}
return next.flush();
} else {
throw msg.deflaterState();
}
}
}
}
@Override
public int writeFinal(ByteBuffer src) throws IOException {
//todo: non-naive implementations of this
return Conduits.writeFinalBasic(this, src);
}
@Override
public long writeFinal(ByteBuffer[] srcs, int offset, int length) throws IOException {
//todo: non-naive implementations of this
return Conduits.writeFinalBasic(this, srcs, offset, length);
}
public void terminateWrites() throws IOException {
deflater.finish();
}
public void truncateWrites() throws IOException {
deflater.finish();
next.truncateWrites();
}
}