AbstractQueue

This class provides skeletal implementations of some {@link Queue} operations. The implementations in this class are appropriate when the base implementation does <em>not</em> allow {@code null} elements. Methods {@link #add add}, {@link #remove remove}, and {@link #element element} are based on {@link #offer offer}, {@link #poll poll}, and {@link #peek peek}, respectively, but throw exceptions instead of indicating failure via {@code false} or {@code null} returns.

<p>A {@code Queue} implementation that extends this class must minimally define a method {@link Queue#offer} which does not permit insertion of {@code null} elements, along with methods {@link Queue#peek}, {@link Queue#poll}, {@link Collection#size}, and {@link Collection#iterator}. Typically, additional methods will be overridden as well. If these requirements cannot be met, consider instead subclassing {@link AbstractCollection}.

<p>This class is a member of the <a href="{@docRoot}/java.base/java/util/package-summary.html#CollectionsFramework"> Java Collections Framework</a>.

@author Doug Lea @param (E) the type of elements held in this queue

abstract

class AbstractQueue : AbstractCollection!(E), Queue!(E)(

) {

bool addAll(Collection!E c);

bool opEquals(IObject o);

bool opEquals(Object o);

size_t toHash();

string toString();

}

Constructors

this this(): Constructor for use by subclasses.

Members

Functions

add bool add(E e): 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.
addAll bool addAll(Collection!E c): Adds all of the elements in the specified collection to this queue. Attempts to addAll of a queue to itself result in {@code IllegalArgumentException}. Further, the behavior of this operation is undefined if the specified collection is modified while the operation is in progress.
clear void clear(): Removes all of the elements from this queue. The queue will be empty after this call returns.
element E element(): 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.
opEquals bool opEquals(IObject o): Undocumented in source. Be warned that the author may not have intended to support it.
opEquals bool opEquals(Object o): Undocumented in source. Be warned that the author may not have intended to support it.
remove E remove(): 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.
toHash size_t toHash(): Undocumented in source. Be warned that the author may not have intended to support it.
toString string toString(): Undocumented in source. Be warned that the author may not have intended to support it.

AbstractQueue

Constructors

Members

Functions

Meta

Source