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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).
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/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 *   https://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.netty.channel;

import io.netty.util.concurrent.RejectedExecutionHandler;
import io.netty.util.concurrent.RejectedExecutionHandlers;
import io.netty.util.concurrent.SingleThreadEventExecutor;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.SystemPropertyUtil;
import io.netty.util.internal.UnstableApi;

import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Queue;
import java.util.concurrent.Executor;
import java.util.concurrent.ThreadFactory;

/**
 * Abstract base class for {@link EventLoop}s that execute all its submitted tasks in a single thread.
 *
 */
public abstract class SingleThreadEventLoop extends SingleThreadEventExecutor implements EventLoop {

    protected static final int DEFAULT_MAX_PENDING_TASKS = Math.max(16,
            SystemPropertyUtil.getInt("io.netty.eventLoop.maxPendingTasks", Integer.MAX_VALUE));

    private final Queue tailTasks;

    protected SingleThreadEventLoop(EventLoopGroup parent, ThreadFactory threadFactory, boolean addTaskWakesUp) {
        this(parent, threadFactory, addTaskWakesUp, DEFAULT_MAX_PENDING_TASKS, RejectedExecutionHandlers.reject());
    }

    protected SingleThreadEventLoop(EventLoopGroup parent, Executor executor, boolean addTaskWakesUp) {
        this(parent, executor, addTaskWakesUp, DEFAULT_MAX_PENDING_TASKS, RejectedExecutionHandlers.reject());
    }

    protected SingleThreadEventLoop(EventLoopGroup parent, ThreadFactory threadFactory,
                                    boolean addTaskWakesUp, int maxPendingTasks,
                                    RejectedExecutionHandler rejectedExecutionHandler) {
        super(parent, threadFactory, addTaskWakesUp, maxPendingTasks, rejectedExecutionHandler);
        tailTasks = newTaskQueue(maxPendingTasks);
    }

    protected SingleThreadEventLoop(EventLoopGroup parent, Executor executor,
                                    boolean addTaskWakesUp, int maxPendingTasks,
                                    RejectedExecutionHandler rejectedExecutionHandler) {
        super(parent, executor, addTaskWakesUp, maxPendingTasks, rejectedExecutionHandler);
        tailTasks = newTaskQueue(maxPendingTasks);
    }

    protected SingleThreadEventLoop(EventLoopGroup parent, Executor executor,
                                    boolean addTaskWakesUp, Queue taskQueue, Queue tailTaskQueue,
                                    RejectedExecutionHandler rejectedExecutionHandler) {
        super(parent, executor, addTaskWakesUp, taskQueue, rejectedExecutionHandler);
        tailTasks = ObjectUtil.checkNotNull(tailTaskQueue, "tailTaskQueue");
    }

    @Override
    public EventLoopGroup parent() {
        return (EventLoopGroup) super.parent();
    }

    @Override
    public EventLoop next() {
        return (EventLoop) super.next();
    }

    @Override
    public ChannelFuture register(Channel channel) {
        return register(new DefaultChannelPromise(channel, this));
    }

    @Override
    public ChannelFuture register(final ChannelPromise promise) {
        ObjectUtil.checkNotNull(promise, "promise");
        promise.channel().unsafe().register(this, promise);
        return promise;
    }

    @Deprecated
    @Override
    public ChannelFuture register(final Channel channel, final ChannelPromise promise) {
        ObjectUtil.checkNotNull(promise, "promise");
        ObjectUtil.checkNotNull(channel, "channel");
        channel.unsafe().register(this, promise);
        return promise;
    }

    /**
     * Adds a task to be run once at the end of next (or current) {@code eventloop} iteration.
     *
     * @param task to be added.
     */
    public final void executeAfterEventLoopIteration(Runnable task) {
        ObjectUtil.checkNotNull(task, "task");
        if (isShutdown()) {
            reject();
        }

        if (!tailTasks.offer(task)) {
            reject(task);
        }

        if (wakesUpForTask(task)) {
            wakeup(inEventLoop());
        }
    }

    /**
     * Removes a task that was added previously via {@link #executeAfterEventLoopIteration(Runnable)}.
     *
     * @param task to be removed.
     *
     * @return {@code true} if the task was removed as a result of this call.
     */
    final boolean removeAfterEventLoopIterationTask(Runnable task) {
        return tailTasks.remove(ObjectUtil.checkNotNull(task, "task"));
    }

    @Override
    protected void afterRunningAllTasks() {
        runAllTasksFrom(tailTasks);
    }

    @Override
    protected boolean hasTasks() {
        return super.hasTasks() || !tailTasks.isEmpty();
    }

    @Override
    public int pendingTasks() {
        return super.pendingTasks() + tailTasks.size();
    }

    /**
     * Returns the number of {@link Channel}s registered with this {@link EventLoop} or {@code -1}
     * if operation is not supported. The returned value is not guaranteed to be exact accurate and
     * should be viewed as a best effort.
     */
    @UnstableApi
    public int registeredChannels() {
        return -1;
    }

    /**
     * @return read-only iterator of active {@link Channel}s registered with this {@link EventLoop}.
     *         The returned value is not guaranteed to be exact accurate and
     *         should be viewed as a best effort. This method is expected to be called from within
     *         event loop.
     * @throws UnsupportedOperationException if operation is not supported by implementation.
     */
    @UnstableApi
    public Iterator registeredChannelsIterator() {
        throw new UnsupportedOperationException("registeredChannelsIterator");
    }

    protected static final class ChannelsReadOnlyIterator implements Iterator {
        private final Iterator channelIterator;

        public ChannelsReadOnlyIterator(Iterable channelIterable) {
            this.channelIterator =
                    ObjectUtil.checkNotNull(channelIterable, "channelIterable").iterator();
        }

        @Override
        public boolean hasNext() {
            return channelIterator.hasNext();
        }

        @Override
        public Channel next() {
            return channelIterator.next();
        }

        @Override
        public void remove() {
            throw new UnsupportedOperationException("remove");
        }

        @SuppressWarnings("unchecked")
        public static  Iterator empty() {
            return (Iterator) EMPTY;
        }

        private static final Iterator