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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 2008 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.util.concurrent.TimeUnit;
import java.util.concurrent.CancellationException;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.LockSupport;
import static org.xnio._private.Messages.futureMsg;
/**
* An abstract base class for {@code IoFuture} objects. Used to easily produce implementations.
*
* @param the type of result that this operation produces
*/
public abstract class AbstractIoFuture implements IoFuture {
@SuppressWarnings("unchecked")
private final AtomicReference> stateRef = new AtomicReference<>((State) ST_INITIAL);
private static final State ST_INITIAL = new InitialState<>();
private static final State ST_CANCELLED = new CancelledState<>();
static abstract class State {
abstract Status getStatus();
abstract void notifyDone(AbstractIoFuture future, T result);
abstract void notifyFailed(AbstractIoFuture future, IOException exception);
abstract void notifyCancelled(AbstractIoFuture future);
abstract void cancel();
abstract boolean cancelRequested();
State withWaiter(final Thread thread) {
return new WaiterState(this, thread);
}
State withNotifier(final Executor executor, final AbstractIoFuture future, final Notifier notifier, final A attachment) {
return new NotifierState(this, notifier, attachment);
}
State withCancelHandler(final Cancellable cancellable) {
return new CancellableState(this, cancellable);
}
T getResult() {
throw new IllegalStateException();
}
IOException getException() {
throw new IllegalStateException();
}
}
private static abstract class NestedState extends State {
private final State next;
public NestedState(final State next) {
this.next = next;
}
/**
* Perform any actions that need to be executed when future is done, delegation of done notification to next is
* taken care of by invoker.
*
* @param future the future
* @param result the result
*/
protected abstract void doNotifyDone(AbstractIoFuture future, T result);
@Override
public void notifyDone(AbstractIoFuture future, T result) {
doNotifyDone(future, result);
if (next instanceof NestedState) {
NestedState current = this;
do {
current = (NestedState) current.next;
current.doNotifyDone(future, result);
} while (current.next instanceof NestedState);
current.next.notifyDone(future, result);
} else {
next.notifyDone(future, result);
}
}
/**
* Perform any actions that need to be done at this state for handling failure, delegation of failure
* notification to next is taken care of by invoker
*
* @param future the future
* @param exception the failure
*/
protected abstract void doNotifyFailed(AbstractIoFuture future, IOException exception);
@Override
public void notifyFailed(AbstractIoFuture future, IOException exception) {
doNotifyFailed(future, exception);
if (next instanceof NestedState) {
NestedState current = this;
do {
current = (NestedState) current.next;
current.doNotifyFailed(future, exception);
} while (current.next instanceof NestedState);
current.next.notifyFailed(future, exception);
} else {
next.notifyFailed(future, exception);
}
}
/**
* Perform any actions that need to be done at this state for handling cancellation, delegation of cancellation
* notification to next is taken care of by invoker
*
* @param future the future
*/
protected abstract void doNotifyCancelled(AbstractIoFuture future);
@Override
public void notifyCancelled(AbstractIoFuture future) {
doNotifyCancelled(future);
if (next instanceof NestedState) {
NestedState current = this;
do {
current = (NestedState) current.next;
current.doNotifyCancelled(future);
} while (current.next instanceof NestedState);
current.next.notifyCancelled(future);
} else {
next.notifyCancelled(future);
}
}
/**
* Perform any actions that need to be done at this state for cancellation. Delegation of cancellation to next
* is taken care of by invoker.
*/
protected abstract void doCancel();
/**
* Just delegate cancel() to first next state in the nested chain that is not a NestedState.
*/
@Override
public void cancel() {
doCancel();
if (next instanceof NestedState) {
NestedState current = this;
do {
current = (NestedState) current.next;
current.doCancel();
} while (current.next instanceof NestedState);
current.next.cancel();
} else {
next.cancel();
}
}
/**
* Return {@code true} to indicate that, at this state, cancel is requested. If returns false, invoker
* will check for inner next states in the chain until it finds a positive result or the final state in the
* chain.
*
* @return {@code true} to indicate that cancel is requested; {@code false} to delegate response to nested
* state.
*/
protected abstract boolean isCancelRequested();
@Override
public boolean cancelRequested() {
if (isCancelRequested()) {
return true;
}
if (next instanceof NestedState) {
NestedState current = this;
do {
current = (NestedState) current.next;
if (current.isCancelRequested()) {
return true;
}
} while (current.next instanceof NestedState);
return current.next.cancelRequested();
} else {
return next.cancelRequested();
}
}
}
static final class InitialState extends State {
Status getStatus() {
return Status.WAITING;
}
void notifyDone(final AbstractIoFuture future, final T result) {
}
void notifyFailed(final AbstractIoFuture future, final IOException exception) {
}
void notifyCancelled(final AbstractIoFuture future) {
}
void cancel() {
}
boolean cancelRequested() {
return false;
}
}
static final class CompleteState extends State {
private final T result;
CompleteState(final T result) {
this.result = result;
}
Status getStatus() {
return Status.DONE;
}
void notifyDone(final AbstractIoFuture future, final T result) {
}
void notifyFailed(final AbstractIoFuture future, final IOException exception) {
}
void notifyCancelled(final AbstractIoFuture future) {
}
void cancel() {
}
State withCancelHandler(final Cancellable cancellable) {
return this;
}
State withWaiter(final Thread thread) {
return this;
}
State withNotifier(final Executor executor, final AbstractIoFuture future, final Notifier notifier, final A attachment) {
future.runNotifier(new NotifierRunnable(notifier, future, attachment));
return this;
}
T getResult() {
return result;
}
boolean cancelRequested() {
return false;
}
}
static final class FailedState extends State {
private final IOException exception;
FailedState(final IOException exception) {
this.exception = exception;
}
Status getStatus() {
return Status.FAILED;
}
void notifyDone(final AbstractIoFuture future, final T result) {
}
void notifyFailed(final AbstractIoFuture future, final IOException exception) {
}
void notifyCancelled(final AbstractIoFuture future) {
}
void cancel() {
}
State withCancelHandler(final Cancellable cancellable) {
return this;
}
State withWaiter(final Thread thread) {
return this;
}
State withNotifier(final Executor executor, final AbstractIoFuture future, final Notifier notifier, final A attachment) {
future.runNotifier(new NotifierRunnable(notifier, future, attachment));
return this;
}
IOException getException() {
return exception;
}
boolean cancelRequested() {
return false;
}
}
static final class CancelledState extends State {
CancelledState() {
}
Status getStatus() {
return Status.CANCELLED;
}
void notifyDone(final AbstractIoFuture future, final T result) {
}
void notifyFailed(final AbstractIoFuture future, final IOException exception) {
}
void notifyCancelled(final AbstractIoFuture future) {
}
void cancel() {
}
State withCancelHandler(final Cancellable cancellable) {
try {
cancellable.cancel();
} catch (Throwable ignored) {}
return this;
}
State withNotifier(final Executor executor, final AbstractIoFuture future, final Notifier notifier, final A attachment) {
future.runNotifier(new NotifierRunnable(notifier, future, attachment));
return this;
}
State withWaiter(final Thread thread) {
return this;
}
boolean cancelRequested() {
return true;
}
}
static final class NotifierState extends NestedState {
final Notifier notifier;
final A attachment;
NotifierState(final State next, final Notifier notifier, final A attachment) {
super(next);
this.notifier = notifier;
this.attachment = attachment;
}
Status getStatus() {
return Status.WAITING;
}
@Override
protected void doNotifyDone(final AbstractIoFuture future, final T result) {
doNotify(future);
}
@Override
protected void doNotifyFailed(final AbstractIoFuture future, final IOException exception) {
doNotify(future);
}
@Override
protected void doNotifyCancelled(final AbstractIoFuture future) {
doNotify(future);
}
@Override
protected void doCancel() {
}
private void doNotify(final AbstractIoFuture future) {
future.runNotifier(new NotifierRunnable(notifier, future, attachment));
}
@Override
protected boolean isCancelRequested() {
return false;
}
}
static final class WaiterState extends NestedState {
final Thread waiter;
WaiterState(final State next, final Thread waiter) {
super(next);
this.waiter = waiter;
}
Status getStatus() {
return Status.WAITING;
}
@Override
protected void doNotifyDone(final AbstractIoFuture future, final T result) {
LockSupport.unpark(waiter);
}
@Override
protected void doNotifyFailed(final AbstractIoFuture future, final IOException exception) {
LockSupport.unpark(waiter);
}
@Override
protected void doNotifyCancelled(final AbstractIoFuture future) {
LockSupport.unpark(waiter);
}
@Override
protected void doCancel() {}
@Override
protected boolean isCancelRequested() {
return false;
}
}
static final class CancellableState extends NestedState {
final Cancellable cancellable;
CancellableState(final State next, final Cancellable cancellable) {
super(next);
this.cancellable = cancellable;
}
Status getStatus() {
return Status.WAITING;
}
@Override
protected void doNotifyDone(final AbstractIoFuture future, final T result) {
}
@Override
protected void doNotifyFailed(final AbstractIoFuture future, final IOException exception) {
}
@Override
protected void doNotifyCancelled(final AbstractIoFuture future) {
}
@Override
protected void doCancel() {
try {
cancellable.cancel();
} catch (Throwable ignored) {}
}
@Override
protected boolean isCancelRequested() {
return false;
}
}
static final class CancelRequestedState extends NestedState {
CancelRequestedState(final State next) {
super(next);
}
Status getStatus() {
return Status.WAITING;
}
@Override
protected void doNotifyDone(final AbstractIoFuture future, final T result) {
}
@Override
protected void doNotifyFailed(final AbstractIoFuture future, final IOException exception) {
}
@Override
protected void doNotifyCancelled(final AbstractIoFuture future) {
}
@Override
protected void doCancel() {
// terminate
}
@Override
protected boolean isCancelRequested() {
return true;
}
}
/**
* Construct a new instance.
*/
protected AbstractIoFuture() {
}
/**
* {@inheritDoc}
*/
public Status getStatus() {
return getState().getStatus();
}
private State getState() {
return stateRef.get();
}
private boolean compareAndSetState(State expect, State update) {
return stateRef.compareAndSet(expect, update);
}
/**
* {@inheritDoc}
*/
public Status await() {
final Thread thread = Thread.currentThread();
State state;
for (;;) {
state = getState();
if (state.getStatus() != Status.WAITING) {
return state.getStatus();
}
Xnio.checkBlockingAllowed();
State withWaiter = state.withWaiter(thread);
if (compareAndSetState(state, withWaiter)) {
boolean intr = Thread.interrupted();
try {
do {
LockSupport.park(this);
if (Thread.interrupted()) intr = true;
state = getState();
} while (state.getStatus() == Status.WAITING);
return state.getStatus();
} finally {
if (intr) thread.interrupt();
}
}
// retry
}
}
/**
* {@inheritDoc}
*/
public Status await(long time, final TimeUnit timeUnit) {
if (time < 0L) {
time = 0L;
}
long duration = timeUnit.toNanos(time);
long now = System.nanoTime();
long tick;
final Thread thread = Thread.currentThread();
State state;
for (;;) {
state = getState();
if (state.getStatus() != Status.WAITING || duration == 0L) {
return state.getStatus();
}
Xnio.checkBlockingAllowed();
State withWaiter = state.withWaiter(thread);
if (compareAndSetState(state, withWaiter)) {
boolean intr = Thread.interrupted();
try {
do {
LockSupport.parkNanos(this, duration);
if (Thread.interrupted()) intr = true;
state = getState();
duration -= (tick = System.nanoTime()) - now;
now = tick;
} while (state.getStatus() == Status.WAITING && duration > 0L);
return state.getStatus();
} finally {
if (intr) thread.interrupt();
}
}
// retry
}
}
/**
* {@inheritDoc}
*/
public Status awaitInterruptibly() throws InterruptedException {
final Thread thread = Thread.currentThread();
State state;
for (;;) {
state = getState();
if (state.getStatus() != Status.WAITING) {
return state.getStatus();
}
Xnio.checkBlockingAllowed();
if (Thread.interrupted()) throw new InterruptedException();
State withWaiter = state.withWaiter(thread);
if (compareAndSetState(state, withWaiter)) {
do {
LockSupport.park(this);
if (Thread.interrupted()) throw new InterruptedException();
state = getState();
} while (state.getStatus() == Status.WAITING);
return state.getStatus();
}
// retry
}
}
/**
* {@inheritDoc}
*/
public Status awaitInterruptibly(long time, final TimeUnit timeUnit) throws InterruptedException {
if (time < 0L) {
time = 0L;
}
long duration = timeUnit.toNanos(time);
long now = System.nanoTime();
long tick;
final Thread thread = Thread.currentThread();
State state;
for (;;) {
state = getState();
if (state.getStatus() != Status.WAITING || duration == 0L) {
return state.getStatus();
}
Xnio.checkBlockingAllowed();
if (Thread.interrupted()) throw new InterruptedException();
State withWaiter = state.withWaiter(thread);
if (compareAndSetState(state, withWaiter)) {
do {
LockSupport.parkNanos(this, duration);
if (Thread.interrupted()) throw new InterruptedException();
state = getState();
duration -= (tick = System.nanoTime()) - now;
now = tick;
} while (state.getStatus() == Status.WAITING && duration > 0L);
return state.getStatus();
}
// retry
}
}
/**
* {@inheritDoc}
*/
@SuppressWarnings({"unchecked"})
public T get() throws IOException, CancellationException {
switch (await()) {
case DONE: return getState().getResult();
case FAILED: throw getState().getException();
case CANCELLED: throw futureMsg.opCancelled();
default: throw new IllegalStateException();
}
}
/**
* {@inheritDoc}
*/
@SuppressWarnings({"unchecked"})
public T getInterruptibly() throws IOException, InterruptedException, CancellationException {
switch (awaitInterruptibly()) {
case DONE: return getState().getResult();
case FAILED: throw getState().getException();
case CANCELLED: throw futureMsg.opCancelled();
default: throw new IllegalStateException();
}
}
/**
* {@inheritDoc}
*/
public IOException getException() throws IllegalStateException {
return getState().getException();
}
/**
* {@inheritDoc}
*/
public IoFuture addNotifier(final Notifier notifier, final A attachment) {
State oldState, newState;
do {
oldState = getState();
newState = oldState.withNotifier(getNotifierExecutor(), this, notifier, attachment);
} while (! compareAndSetState(oldState, newState));
return this;
}
/**
* Set the exception for this operation. Any threads blocking on this instance will be unblocked.
*
* @param exception the exception to set
* @return {@code false} if the operation was already completed, {@code true} otherwise
*/
protected boolean setException(IOException exception) {
State oldState;
oldState = getState();
if (oldState.getStatus() != Status.WAITING) {
return false;
} else {
State newState = new FailedState(exception);
while (! compareAndSetState(oldState, newState)) {
oldState = getState();
if (oldState.getStatus() != Status.WAITING) {
return false;
}
}
}
oldState.notifyFailed(this, exception);
return true;
}
/**
* Set the result for this operation. Any threads blocking on this instance will be unblocked.
*
* @param result the result to set
* @return {@code false} if the operation was already completed, {@code true} otherwise
*/
protected boolean setResult(T result) {
State oldState;
oldState = getState();
if (oldState.getStatus() != Status.WAITING) {
return false;
} else {
State newState = new CompleteState<>(result);
while (! compareAndSetState(oldState, newState)) {
oldState = getState();
if (oldState.getStatus() != Status.WAITING) {
return false;
}
}
}
oldState.notifyDone(this, result);
return true;
}
/**
* Acknowledge the cancellation of this operation.
*
* @return {@code false} if the operation was already completed, {@code true} otherwise
*/
protected boolean setCancelled() {
State oldState;
oldState = getState();
if (oldState.getStatus() != Status.WAITING) {
return false;
} else {
@SuppressWarnings("unchecked")
State newState = (State) ST_CANCELLED;
while (! compareAndSetState(oldState, newState)) {
oldState = getState();
if (oldState.getStatus() != Status.WAITING) {
return false;
}
}
}
oldState.notifyCancelled(this);
return true;
}
/**
* Cancel an operation. The actual cancel may be synchronous or asynchronous. Implementers will use this method
* to initiate the cancel; use the {@link #setCancelled()} method to indicate that the cancel was successful. The
* default implementation calls any registered cancel handlers.
*
* @return this {@code IoFuture} instance
*/
public IoFuture cancel() {
State state;
do {
state = getState();
if (state.getStatus() != Status.WAITING || state.cancelRequested()) return this;
} while (! compareAndSetState(state, new CancelRequestedState(state)));
state.cancel();
return this;
}
/**
* Add a cancellation handler. The argument will be cancelled whenever this {@code IoFuture} is cancelled. If
* the {@code IoFuture} is already cancelled when this method is called, the handler will be called directly.
*
* @param cancellable the cancel handler
*/
protected void addCancelHandler(final Cancellable cancellable) {
State oldState, newState;
do {
oldState = getState();
if (oldState.getStatus() != Status.WAITING || oldState.cancelRequested()) {
try {
cancellable.cancel();
} catch (Throwable ignored) {
}
return;
}
newState = oldState.withCancelHandler(cancellable);
if (oldState == newState) return;
} while (! compareAndSetState(oldState, newState));
}
/**
* Run a notifier. Implementors will run the notifier, preferably in another thread. The default implementation
* runs the notifier using the {@code Executor} retrieved via {@link #getNotifierExecutor()}.
*
* @param runnable the runnable task
*/
protected void runNotifier(final Runnable runnable) {
getNotifierExecutor().execute(runnable);
}
/**
* Get the executor used to run asynchronous notifiers. By default, this implementation simply returns the direct
* executor.
*
* @return the executor to use
*/
protected Executor getNotifierExecutor() {
return IoUtils.directExecutor();
}
static class NotifierRunnable implements Runnable {
private final Notifier notifier;
private final IoFuture future;
private final A attachment;
NotifierRunnable(final Notifier notifier, final IoFuture future, final A attachment) {
this.notifier = notifier;
this.future = future;
this.attachment = attachment;
}
public void run() {
try {
notifier.notify(future, attachment);
} catch (Throwable t) {
futureMsg.notifierFailed(t, notifier, attachment);
}
}
}
}