/*
* 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 <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a>
*/
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<
Connection>
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 extends
SocketAddress> A
castAddress(final
Class<A>
type,
SocketAddress address) {
return
type.
isInstance(
address) ?
type.
cast(
address) : null;
}
public final <A extends
SocketAddress> A
getPeerAddress(final
Class<A>
type) {
return
castAddress(
type,
getPeerAddress());
}
public final <A extends
SocketAddress> A
getLocalAddress(final
Class<A>
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> T
getOption(final
Option<T>
option) throws
IOException {
return null;
}
public <T> T
setOption(final
Option<T>
option, final T
value) throws
IllegalArgumentException,
IOException {
return null;
}
}