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 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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
 *
 *   http://www.apache.org/licenses/LICENSE-2.0

### What is a Process { #what-is-a-process }

The word **process** is normally used in a more specific way, only referring to the thing that is running in the operating system (like in the last point above):

* A particular program while it is **running** on the operating system.

 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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
 *
 *   http://www.apache.org/licenses/LICENSE-2.0

    @GuardedBy("this")
    final Queue<Object> labelQueue = new ArrayDeque<>();

    @GuardedBy("this")
    boolean isThreadScheduled;

    PerListenerQueue(L listener, Executor executor) {
      this.listener = checkNotNull(listener);
      this.executor = checkNotNull(executor);
    }

    /** Enqueues an event to be run. */
    synchronized void add(ListenerCallQueue.Event<L> event, Object label) {

        super(WITNESS_ASYNC_NOTIFY);
        this.contextHandle = contextHandle != null ? contextHandle.clone() : new byte[20];
        this.notifications = new ArrayList<>();
    }

    /**
     * Sets the context handle for the async notify request.
     *
     * @param contextHandle the context handle from registration
     */
    public void setContextHandle(byte[] contextHandle) {

    checkArgument(k <= Integer.MAX_VALUE / 2, "k (%s) must be <= Integer.MAX_VALUE / 2", k);
    this.buffer = (T[]) new Object[Math.multiplyExact(k, 2)];
    this.bufferSize = 0;
    this.threshold = null;
  }

  /**
   * Adds {@code elem} as a candidate for the top {@code k} elements. This operation takes amortized
   * O(1) time.
   */
  public void offer(@ParametricNullness T elem) {
    if (k == 0) {

/*
 * © 2017 AgNO3 Gmbh & Co. KG
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of

/*
 * © 2017 AgNO3 Gmbh & Co. KG
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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
 *
 *   http://www.apache.org/licenses/LICENSE-2.0