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/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
*/
package com.xenoamess.commons.primitive.collections.queues;
import com.xenoamess.commons.primitive.Primitive;
import com.xenoamess.commons.primitive.collections.LongCollection;
import com.xenoamess.commons.primitive.collections.lists.linked_lists.LongLinkedList;
import java.util.NoSuchElementException;
import java.util.Queue;
/**
* A collection designed for holding elements prior to processing.
* Besides basic {@link LongCollection} operations, queues provide
* additional insertion, extraction, and inspection operations.
* Each of these methods exists in two forms: one throws an exception
* if the operation fails, the other returns a special value (either
* {@code null} or {@code false}, depending on the operation). The
* latter form of the insert operation is designed specifically for
* use with capacity-restricted {@code Queue} implementations; in most
* implementations, insert operations cannot fail.
*
*
* Summary of Queue methods
*
*
* Throws exception
* Returns special value
*
*
*
*
* Insert
* {@link #add(Long) add(e)}
* {@link #offer(Long) offer(e)}
*
*
* Remove
* {@link #remove() remove()}
* {@link #poll() poll()}
*
*
* Examine
* {@link #element() element()}
* {@link #peek() peek()}
*
*
*
*
* Queues typically, but do not necessarily, order elements in a
* FIFO (first-in-first-out) manner. Among the exceptions are
* priority queues, which order elements according to a supplied
* comparator, or the elements' natural ordering, and LIFO queues (or
* stacks) which order the elements LIFO (last-in-first-out).
* Whatever the ordering used, the head of the queue is that
* element which would be removed by a call to {@link #remove()} or
* {@link #poll()}. In a FIFO queue, all new elements are inserted at
* the tail of the queue. Other kinds of queues may use
* different placement rules. Every {@code Queue} implementation
* must specify its ordering properties.
*
*
The {@link #offer offer} method inserts an element if possible,
* otherwise returning {@code false}. This differs from the {@link
* java.util.Collection#add Collection.add} method, which can fail to
* add an element only by throwing an unchecked exception. The
* {@code offer} method is designed for use when failure is a normal,
* rather than exceptional occurrence, for example, in fixed-capacity
* (or "bounded") queues.
*
*
The {@link #remove()} and {@link #poll()} methods remove and
* return the head of the queue.
* Exactly which element is removed from the queue is a
* function of the queue's ordering policy, which differs from
* implementation to implementation. The {@code remove()} and
* {@code poll()} methods differ only in their behavior when the
* queue is empty: the {@code remove()} method throws an exception,
* while the {@code poll()} method returns {@code null}.
*
*
The {@link #element()} and {@link #peek()} methods return, but do
* not remove, the head of the queue.
*
*
The {@code Queue} interface does not define the blocking queue
* methods, which are common in concurrent programming. These methods,
* which wait for elements to appear or for space to become available, are
* defined in the {@link java.util.concurrent.BlockingQueue} interface, which
* extends this interface.
*
*
{@code Queue} implementations generally do not allow insertion
* of {@code null} elements, although some implementations, such as
* {@link LongLinkedList}, do not prohibit insertion of {@code null}.
* Even in the implementations that permit it, {@code null} should
* not be inserted into a {@code Queue}, as {@code null} is also
* used as a special return value by the {@code poll} method to
* indicate that the queue contains no elements.
*
*
{@code Queue} implementations generally do not define
* element-based versions of methods {@code equals} and
* {@code hashCode} but instead inherit the identity based versions
* from class {@code Object}, because element-based equality is not
* always well-defined for queues with the same elements but different
* ordering properties.
*
*
This interface is a member of the
*
* Java Collections Framework.
*
* @author Doug Lea
* @since 1.5
*/
public interface LongQueue extends Queue, LongCollection, Primitive {
/**
* Inserts the specified element into this queue if it is possible to do so
* immediately without violating capacity restrictions, returning
* {@code true} upon success and throwing an {@code IllegalStateException}
* if no space is currently available.
*
* @param e the element to add
* @return {@code true} (as specified by {@link LongCollection#add})
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this queue
* @throws NullPointerException if the specified element is null and
* this queue does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this queue
*/
@Override
default boolean add(Long e) {
return LongCollection.super.add(e);
}
/**
* Inserts the specified element into this queue if it is possible to do
* so immediately without violating capacity restrictions.
* When using a capacity-restricted queue, this method is generally
* preferable to {@link #add}, which can fail to insert an element only
* by throwing an exception.
*
* @param e the element to add
* @return {@code true} if the element was added to this queue, else
* {@code false}
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this queue
* @throws NullPointerException if the specified element is null and
* this queue does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this queue
*/
@Override
default boolean offer(Long e) {
return this.offerPrimitive(e);
}
/**
* Primitive replacement of offer(Long e)
*
* @param e the element to add
* @return {@code true} if the element was added to this queue, else
* {@code false}
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this queue
* @throws NullPointerException if the specified element is null and
* this queue does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this queue
* @see #offer(Long e)
*/
default boolean offer(long e) {
return this.offerPrimitive(e);
}
/**
* Primitive replacement of offer(Long e)
*
* @param e the element to add
* @return {@code true} if the element was added to this queue, else
* {@code false}
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this queue
* @throws NullPointerException if the specified element is null and
* this queue does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this queue
* @see #offer(Long e)
*/
boolean offerPrimitive(long e);
/**
* Retrieves and removes the head of this queue. This method differs
* from {@link #poll() poll()} only in that it throws an exception if
* this queue is empty.
*
* @return the head of this queue
* @throws NoSuchElementException if this queue is empty
*/
@Override
default Long remove() {
return this.removePrimitive();
}
/**
* Primitive replacement of remove()
*
* @return the head of this queue
* @throws NoSuchElementException if this queue is empty
* @see #remove()
*/
long removePrimitive();
/**
* Retrieves and removes the head of this queue,
* or returns {@code null} if this queue is empty.
*
* @return the head of this queue, or {@code null} if this queue is empty
*/
@Override
default Long poll() {
return this.pollPrimitive();
}
/**
* Primitive replacement of poll()
*
* @return the head of this queue, or {@code null} if this queue is empty
* @see #poll()
*/
long pollPrimitive();
/**
* Retrieves, but does not remove, the head of this queue. This method
* differs from {@link #peek peek} only in that it throws an exception
* if this queue is empty.
*
* @return the head of this queue
* @throws NoSuchElementException if this queue is empty
*/
@Override
default Long element() {
return this.elementPrimitive();
}
/**
* Primitive replacement of element()
*
* @return the head of this queue
* @throws NoSuchElementException if this queue is empty
* @see #element()
*/
long elementPrimitive();
/**
* Retrieves, but does not remove, the head of this queue,
* or returns {@code null} if this queue is empty.
*
* @return the head of this queue, or {@code null} if this queue is empty
*/
@Override
default Long peek() {
return this.peekPrimitive();
}
/**
* Primitive replacement of peek()
*
* @return the head of this queue, or {@code null} if this queue is empty
* @see #peek()
*/
long peekPrimitive();
}