io.undertow.conduits.HeadStreamSinkConduit 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 2014 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* 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 io.undertow.conduits;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.FileChannel;
import org.xnio.IoUtils;
import org.xnio.channels.StreamSourceChannel;
import org.xnio.conduits.AbstractStreamSinkConduit;
import org.xnio.conduits.ConduitWritableByteChannel;
import org.xnio.conduits.Conduits;
import org.xnio.conduits.StreamSinkConduit;
import static org.xnio.Bits.allAreClear;
import static org.xnio.Bits.anyAreSet;
/**
* A conduit that discards all data written to it. This allows head requests to 'just work', as all data written
* will be discarded.
*
* @author Stuart Douglas
*/
public final class HeadStreamSinkConduit extends AbstractStreamSinkConduit {
private final ConduitListener finishListener;
private int state;
private final boolean shutdownDelegate;
private static final int FLAG_CLOSE_REQUESTED = 1;
private static final int FLAG_CLOSE_COMPLETE = 1 << 1;
private static final int FLAG_FINISHED_CALLED = 1 << 2;
/**
* Construct a new instance.
*
* @param next the next channel
* @param finishListener the listener to call when the channel is closed or the length is reached
*/
public HeadStreamSinkConduit(final StreamSinkConduit next, final ConduitListener finishListener) {
this(next, finishListener, false);
}
/**
* Construct a new instance.
*
* @param next the next channel
* @param finishListener the listener to call when the channel is closed or the length is reached
*/
public HeadStreamSinkConduit(final StreamSinkConduit next, final ConduitListener finishListener, boolean shutdownDelegate) {
super(next);
this.finishListener = finishListener;
this.shutdownDelegate = shutdownDelegate;
}
public int write(final ByteBuffer src) throws IOException {
if (anyAreSet(state, FLAG_CLOSE_COMPLETE)) {
throw new ClosedChannelException();
}
int remaining = src.remaining();
src.position(src.position() + remaining);
return remaining;
}
public long write(final ByteBuffer[] srcs, final int offset, final int length) throws IOException {
if (anyAreSet(state, FLAG_CLOSE_COMPLETE)) {
throw new ClosedChannelException();
}
long total = 0;
for (int i = offset; i < offset + length; ++i) {
ByteBuffer src = srcs[i];
int remaining = src.remaining();
total += remaining;
src.position(src.position() + remaining);
}
return total;
}
@Override
public int writeFinal(ByteBuffer src) throws IOException {
return Conduits.writeFinalBasic(this, src);
}
@Override
public long writeFinal(ByteBuffer[] srcs, int offset, int length) throws IOException {
return Conduits.writeFinalBasic(this, srcs, offset, length);
}
@Override
public long transferFrom(final FileChannel src, final long position, final long count) throws IOException {
if (anyAreSet(state, FLAG_CLOSE_COMPLETE)) {
throw new ClosedChannelException();
}
return src.transferTo(position, count, new ConduitWritableByteChannel(this));
}
@Override
public long transferFrom(final StreamSourceChannel source, final long count, final ByteBuffer throughBuffer) throws IOException {
if (anyAreSet(state, FLAG_CLOSE_COMPLETE)) {
throw new ClosedChannelException();
}
return IoUtils.transfer(source, count, throughBuffer, new ConduitWritableByteChannel(this));
}
public boolean flush() throws IOException {
int val = state;
if (anyAreSet(val, FLAG_CLOSE_COMPLETE)) {
return true;
}
boolean flushed = false;
try {
return flushed = next.flush();
} finally {
exitFlush(val, flushed);
}
}
public void suspendWrites() {
long val = state;
if (anyAreSet(val, FLAG_CLOSE_COMPLETE)) {
return;
}
next.suspendWrites();
}
public void resumeWrites() {
long val = state;
if (anyAreSet(val, FLAG_CLOSE_COMPLETE)) {
return;
}
next.resumeWrites();
}
public boolean isWriteResumed() {
// not perfect but not provably wrong either...
return allAreClear(state, FLAG_CLOSE_COMPLETE) && next.isWriteResumed();
}
public void wakeupWrites() {
long val = state;
if (anyAreSet(val, FLAG_CLOSE_COMPLETE)) {
return;
}
next.wakeupWrites();
}
public void terminateWrites() throws IOException {
int oldVal, newVal;
oldVal = state;
if (anyAreSet(oldVal, FLAG_CLOSE_REQUESTED | FLAG_CLOSE_COMPLETE)) {
// no action necessary
return;
}
newVal = oldVal | FLAG_CLOSE_REQUESTED;
state = newVal;
if(shutdownDelegate) {
next.terminateWrites();
}
}
private void exitFlush(int oldVal, boolean flushed) {
int newVal = oldVal;
boolean callFinish = false;
if (anyAreSet(oldVal, FLAG_CLOSE_REQUESTED) && flushed) {
newVal |= FLAG_CLOSE_COMPLETE;
if (!anyAreSet(oldVal, FLAG_FINISHED_CALLED)) {
newVal |= FLAG_FINISHED_CALLED;
callFinish = true;
}
state = newVal;
if (callFinish) {
if (finishListener != null) {
finishListener.handleEvent(this);
}
}
}
}
}