org.xnio.Connection Maven / Gradle / Ivy
/*
* 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;
import java.io.IOException;
import java.net.SocketAddress;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import org.xnio.channels.CloseableChannel;
import org.xnio.channels.ConnectedChannel;
import static org.xnio.Bits.allAreClear;
import static org.xnio.Bits.allAreSet;
import static org.xnio.Bits.anyAreClear;
/**
* The base for all connections.
*
* @author David M. Lloyd
*/
public abstract class Connection implements CloseableChannel, ConnectedChannel {
protected final XnioIoThread thread;
@SuppressWarnings("unused")
private volatile int state;
private static final int FLAG_READ_CLOSED = 0b0001;
private static final int FLAG_WRITE_CLOSED = 0b0010;
private static final AtomicIntegerFieldUpdater stateUpdater = AtomicIntegerFieldUpdater.newUpdater(Connection.class, "state");
/**
* Construct a new instance.
*
* @param thread the I/O thread of this connection
*/
protected Connection(final XnioIoThread thread) {
this.thread = thread;
}
private static A castAddress(final Class type, SocketAddress address) {
return type.isInstance(address) ? type.cast(address) : null;
}
public final A getPeerAddress(final Class type) {
return castAddress(type, getPeerAddress());
}
public final A getLocalAddress(final Class type) {
return castAddress(type, getLocalAddress());
}
public final XnioWorker getWorker() {
return thread.getWorker();
}
public XnioIoThread getIoThread() {
return thread;
}
/**
* Indicate that reads have been closed on this connection.
*
* @return {@code true} if read closure was successfully indicated; {@code false} if this method has already been called
*/
protected boolean readClosed() {
int oldVal, newVal;
do {
oldVal = state;
if (allAreSet(oldVal, FLAG_READ_CLOSED)) {
return false;
}
newVal = oldVal | FLAG_READ_CLOSED;
} while (! stateUpdater.compareAndSet(this, oldVal, newVal));
if (allAreSet(newVal, FLAG_READ_CLOSED | FLAG_WRITE_CLOSED)) {
try {
closeAction();
} catch (Throwable ignored) {}
invokeCloseListener();
}
return true;
}
/**
* Indicate that writes have been closed on this connection.
*
* @return {@code true} if write closure was successfully indicated; {@code false} if this method has already been called
*/
protected boolean writeClosed() {
int oldVal, newVal;
do {
oldVal = state;
if (allAreSet(oldVal, FLAG_WRITE_CLOSED)) {
return false;
}
newVal = oldVal | FLAG_WRITE_CLOSED;
} while (! stateUpdater.compareAndSet(this, oldVal, newVal));
if (allAreSet(newVal, FLAG_READ_CLOSED | FLAG_WRITE_CLOSED)) {
try {
closeAction();
} catch (Throwable ignored) {}
invokeCloseListener();
}
return true;
}
public final void close() throws IOException {
int oldVal, newVal;
do {
oldVal = state;
if (allAreSet(oldVal, FLAG_WRITE_CLOSED | FLAG_READ_CLOSED)) {
return;
}
newVal = oldVal | FLAG_READ_CLOSED | FLAG_WRITE_CLOSED;
} while (! stateUpdater.compareAndSet(this, oldVal, newVal));
try {
closeAction();
} finally {
if (allAreClear(oldVal, FLAG_WRITE_CLOSED)) try {
notifyWriteClosed();
} catch (Throwable ignored) {
}
if (allAreClear(oldVal, FLAG_READ_CLOSED)) try {
notifyReadClosed();
} catch (Throwable ignored) {
}
invokeCloseListener();
}
}
/**
* Determine whether reads have been shut down on this connection.
*
* @return {@code true} if reads were shut down
*/
public boolean isReadShutdown() {
return allAreSet(state, FLAG_READ_CLOSED);
}
/**
* Determine whether writes have been shut down on this connection.
*
* @return {@code true} if writes were shut down
*/
public boolean isWriteShutdown() {
return allAreSet(state, FLAG_WRITE_CLOSED);
}
public boolean isOpen() {
return anyAreClear(state, FLAG_READ_CLOSED | FLAG_WRITE_CLOSED);
}
/**
* Indicate to conduit handlers that writes have been closed.
*/
protected abstract void notifyWriteClosed();
/**
* Indicate to conduit handlers that reads have been closed.
*/
protected abstract void notifyReadClosed();
abstract void invokeCloseListener();
/**
* The close action to perform on this connection.
*
* @throws IOException if close fails
*/
protected void closeAction() throws IOException {}
public boolean supportsOption(final Option option) {
return false;
}
public T getOption(final Option option) throws IOException {
return null;
}
public T setOption(final Option option, final T value) throws IllegalArgumentException, IOException {
return null;
}
}