diff -r 3392f250c784 -r ecbd252fd3a7 emul/compact/src/main/java/java/util/LinkedList.java --- a/emul/compact/src/main/java/java/util/LinkedList.java Fri Mar 22 16:59:47 2013 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,1100 +0,0 @@ -/* - * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. - * 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 - * questions. - */ - -package java.util; - -/** - * Doubly-linked list implementation of the {@code List} and {@code Deque} - * interfaces. Implements all optional list operations, and permits all - * elements (including {@code null}). - * - *

All of the operations perform as could be expected for a doubly-linked - * list. Operations that index into the list will traverse the list from - * the beginning or the end, whichever is closer to the specified index. - * - *

Note that this implementation is not synchronized. - * If multiple threads access a linked list concurrently, and at least - * one of the threads modifies the list structurally, it must be - * synchronized externally. (A structural modification is any operation - * that adds or deletes one or more elements; merely setting the value of - * an element is not a structural modification.) This is typically - * accomplished by synchronizing on some object that naturally - * encapsulates the list. - * - * If no such object exists, the list should be "wrapped" using the - * {@link Collections#synchronizedList Collections.synchronizedList} - * method. This is best done at creation time, to prevent accidental - * unsynchronized access to the list:

- *   List list = Collections.synchronizedList(new LinkedList(...));
- * - *

The iterators returned by this class's {@code iterator} and - * {@code listIterator} methods are fail-fast: if the list is - * structurally modified at any time after the iterator is created, in - * any way except through the Iterator's own {@code remove} or - * {@code add} methods, the iterator will throw a {@link - * ConcurrentModificationException}. Thus, in the face of concurrent - * modification, the iterator fails quickly and cleanly, rather than - * risking arbitrary, non-deterministic behavior at an undetermined - * time in the future. - * - *

Note that the fail-fast behavior of an iterator cannot be guaranteed - * as it is, generally speaking, impossible to make any hard guarantees in the - * presence of unsynchronized concurrent modification. Fail-fast iterators - * throw {@code ConcurrentModificationException} on a best-effort basis. - * Therefore, it would be wrong to write a program that depended on this - * exception for its correctness: the fail-fast behavior of iterators - * should be used only to detect bugs. - * - *

This class is a member of the - * - * Java Collections Framework. - * - * @author Josh Bloch - * @see List - * @see ArrayList - * @since 1.2 - * @param the type of elements held in this collection - */ - -public class LinkedList - extends AbstractSequentialList - implements List, Deque, Cloneable, java.io.Serializable -{ - transient int size = 0; - - /** - * Pointer to first node. - * Invariant: (first == null && last == null) || - * (first.prev == null && first.item != null) - */ - transient Node first; - - /** - * Pointer to last node. - * Invariant: (first == null && last == null) || - * (last.next == null && last.item != null) - */ - transient Node last; - - /** - * Constructs an empty list. - */ - public LinkedList() { - } - - /** - * Constructs a list containing the elements of the specified - * collection, in the order they are returned by the collection's - * iterator. - * - * @param c the collection whose elements are to be placed into this list - * @throws NullPointerException if the specified collection is null - */ - public LinkedList(Collection c) { - this(); - addAll(c); - } - - /** - * Links e as first element. - */ - private void linkFirst(E e) { - final Node f = first; - final Node newNode = new Node<>(null, e, f); - first = newNode; - if (f == null) - last = newNode; - else - f.prev = newNode; - size++; - modCount++; - } - - /** - * Links e as last element. - */ - void linkLast(E e) { - final Node l = last; - final Node newNode = new Node<>(l, e, null); - last = newNode; - if (l == null) - first = newNode; - else - l.next = newNode; - size++; - modCount++; - } - - /** - * Inserts element e before non-null Node succ. - */ - void linkBefore(E e, Node succ) { - // assert succ != null; - final Node pred = succ.prev; - final Node newNode = new Node<>(pred, e, succ); - succ.prev = newNode; - if (pred == null) - first = newNode; - else - pred.next = newNode; - size++; - modCount++; - } - - /** - * Unlinks non-null first node f. - */ - private E unlinkFirst(Node f) { - // assert f == first && f != null; - final E element = f.item; - final Node next = f.next; - f.item = null; - f.next = null; // help GC - first = next; - if (next == null) - last = null; - else - next.prev = null; - size--; - modCount++; - return element; - } - - /** - * Unlinks non-null last node l. - */ - private E unlinkLast(Node l) { - // assert l == last && l != null; - final E element = l.item; - final Node prev = l.prev; - l.item = null; - l.prev = null; // help GC - last = prev; - if (prev == null) - first = null; - else - prev.next = null; - size--; - modCount++; - return element; - } - - /** - * Unlinks non-null node x. - */ - E unlink(Node x) { - // assert x != null; - final E element = x.item; - final Node next = x.next; - final Node prev = x.prev; - - if (prev == null) { - first = next; - } else { - prev.next = next; - x.prev = null; - } - - if (next == null) { - last = prev; - } else { - next.prev = prev; - x.next = null; - } - - x.item = null; - size--; - modCount++; - return element; - } - - /** - * Returns the first element in this list. - * - * @return the first element in this list - * @throws NoSuchElementException if this list is empty - */ - public E getFirst() { - final Node f = first; - if (f == null) - throw new NoSuchElementException(); - return f.item; - } - - /** - * Returns the last element in this list. - * - * @return the last element in this list - * @throws NoSuchElementException if this list is empty - */ - public E getLast() { - final Node l = last; - if (l == null) - throw new NoSuchElementException(); - return l.item; - } - - /** - * Removes and returns the first element from this list. - * - * @return the first element from this list - * @throws NoSuchElementException if this list is empty - */ - public E removeFirst() { - final Node f = first; - if (f == null) - throw new NoSuchElementException(); - return unlinkFirst(f); - } - - /** - * Removes and returns the last element from this list. - * - * @return the last element from this list - * @throws NoSuchElementException if this list is empty - */ - public E removeLast() { - final Node l = last; - if (l == null) - throw new NoSuchElementException(); - return unlinkLast(l); - } - - /** - * Inserts the specified element at the beginning of this list. - * - * @param e the element to add - */ - public void addFirst(E e) { - linkFirst(e); - } - - /** - * Appends the specified element to the end of this list. - * - *

This method is equivalent to {@link #add}. - * - * @param e the element to add - */ - public void addLast(E e) { - linkLast(e); - } - - /** - * Returns {@code true} if this list contains the specified element. - * More formally, returns {@code true} if and only if this list contains - * at least one element {@code e} such that - * (o==null ? e==null : o.equals(e)). - * - * @param o element whose presence in this list is to be tested - * @return {@code true} if this list contains the specified element - */ - public boolean contains(Object o) { - return indexOf(o) != -1; - } - - /** - * Returns the number of elements in this list. - * - * @return the number of elements in this list - */ - public int size() { - return size; - } - - /** - * Appends the specified element to the end of this list. - * - *

This method is equivalent to {@link #addLast}. - * - * @param e element to be appended to this list - * @return {@code true} (as specified by {@link Collection#add}) - */ - public boolean add(E e) { - linkLast(e); - return true; - } - - /** - * Removes the first occurrence of the specified element from this list, - * if it is present. If this list does not contain the element, it is - * unchanged. More formally, removes the element with the lowest index - * {@code i} such that - * (o==null ? get(i)==null : o.equals(get(i))) - * (if such an element exists). Returns {@code true} if this list - * contained the specified element (or equivalently, if this list - * changed as a result of the call). - * - * @param o element to be removed from this list, if present - * @return {@code true} if this list contained the specified element - */ - public boolean remove(Object o) { - if (o == null) { - for (Node x = first; x != null; x = x.next) { - if (x.item == null) { - unlink(x); - return true; - } - } - } else { - for (Node x = first; x != null; x = x.next) { - if (o.equals(x.item)) { - unlink(x); - return true; - } - } - } - return false; - } - - /** - * Appends all of the elements in the specified collection to the end of - * this list, in the order that they are returned by the specified - * collection's iterator. The behavior of this operation is undefined if - * the specified collection is modified while the operation is in - * progress. (Note that this will occur if the specified collection is - * this list, and it's nonempty.) - * - * @param c collection containing elements to be added to this list - * @return {@code true} if this list changed as a result of the call - * @throws NullPointerException if the specified collection is null - */ - public boolean addAll(Collection c) { - return addAll(size, c); - } - - /** - * Inserts all of the elements in the specified collection into this - * list, starting at the specified position. Shifts the element - * currently at that position (if any) and any subsequent elements to - * the right (increases their indices). The new elements will appear - * in the list in the order that they are returned by the - * specified collection's iterator. - * - * @param index index at which to insert the first element - * from the specified collection - * @param c collection containing elements to be added to this list - * @return {@code true} if this list changed as a result of the call - * @throws IndexOutOfBoundsException {@inheritDoc} - * @throws NullPointerException if the specified collection is null - */ - public boolean addAll(int index, Collection c) { - checkPositionIndex(index); - - Object[] a = c.toArray(); - int numNew = a.length; - if (numNew == 0) - return false; - - Node pred, succ; - if (index == size) { - succ = null; - pred = last; - } else { - succ = node(index); - pred = succ.prev; - } - - for (Object o : a) { - @SuppressWarnings("unchecked") E e = (E) o; - Node newNode = new Node<>(pred, e, null); - if (pred == null) - first = newNode; - else - pred.next = newNode; - pred = newNode; - } - - if (succ == null) { - last = pred; - } else { - pred.next = succ; - succ.prev = pred; - } - - size += numNew; - modCount++; - return true; - } - - /** - * Removes all of the elements from this list. - * The list will be empty after this call returns. - */ - public void clear() { - // Clearing all of the links between nodes is "unnecessary", but: - // - helps a generational GC if the discarded nodes inhabit - // more than one generation - // - is sure to free memory even if there is a reachable Iterator - for (Node x = first; x != null; ) { - Node next = x.next; - x.item = null; - x.next = null; - x.prev = null; - x = next; - } - first = last = null; - size = 0; - modCount++; - } - - - // Positional Access Operations - - /** - * Returns the element at the specified position in this list. - * - * @param index index of the element to return - * @return the element at the specified position in this list - * @throws IndexOutOfBoundsException {@inheritDoc} - */ - public E get(int index) { - checkElementIndex(index); - return node(index).item; - } - - /** - * Replaces the element at the specified position in this list with the - * specified element. - * - * @param index index of the element to replace - * @param element element to be stored at the specified position - * @return the element previously at the specified position - * @throws IndexOutOfBoundsException {@inheritDoc} - */ - public E set(int index, E element) { - checkElementIndex(index); - Node x = node(index); - E oldVal = x.item; - x.item = element; - return oldVal; - } - - /** - * Inserts the specified element at the specified position in this list. - * Shifts the element currently at that position (if any) and any - * subsequent elements to the right (adds one to their indices). - * - * @param index index at which the specified element is to be inserted - * @param element element to be inserted - * @throws IndexOutOfBoundsException {@inheritDoc} - */ - public void add(int index, E element) { - checkPositionIndex(index); - - if (index == size) - linkLast(element); - else - linkBefore(element, node(index)); - } - - /** - * Removes the element at the specified position in this list. Shifts any - * subsequent elements to the left (subtracts one from their indices). - * Returns the element that was removed from the list. - * - * @param index the index of the element to be removed - * @return the element previously at the specified position - * @throws IndexOutOfBoundsException {@inheritDoc} - */ - public E remove(int index) { - checkElementIndex(index); - return unlink(node(index)); - } - - /** - * Tells if the argument is the index of an existing element. - */ - private boolean isElementIndex(int index) { - return index >= 0 && index < size; - } - - /** - * Tells if the argument is the index of a valid position for an - * iterator or an add operation. - */ - private boolean isPositionIndex(int index) { - return index >= 0 && index <= size; - } - - /** - * Constructs an IndexOutOfBoundsException detail message. - * Of the many possible refactorings of the error handling code, - * this "outlining" performs best with both server and client VMs. - */ - private String outOfBoundsMsg(int index) { - return "Index: "+index+", Size: "+size; - } - - private void checkElementIndex(int index) { - if (!isElementIndex(index)) - throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); - } - - private void checkPositionIndex(int index) { - if (!isPositionIndex(index)) - throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); - } - - /** - * Returns the (non-null) Node at the specified element index. - */ - Node node(int index) { - // assert isElementIndex(index); - - if (index < (size >> 1)) { - Node x = first; - for (int i = 0; i < index; i++) - x = x.next; - return x; - } else { - Node x = last; - for (int i = size - 1; i > index; i--) - x = x.prev; - return x; - } - } - - // Search Operations - - /** - * Returns the index of the first occurrence of the specified element - * in this list, or -1 if this list does not contain the element. - * More formally, returns the lowest index {@code i} such that - * (o==null ? get(i)==null : o.equals(get(i))), - * or -1 if there is no such index. - * - * @param o element to search for - * @return the index of the first occurrence of the specified element in - * this list, or -1 if this list does not contain the element - */ - public int indexOf(Object o) { - int index = 0; - if (o == null) { - for (Node x = first; x != null; x = x.next) { - if (x.item == null) - return index; - index++; - } - } else { - for (Node x = first; x != null; x = x.next) { - if (o.equals(x.item)) - return index; - index++; - } - } - return -1; - } - - /** - * Returns the index of the last occurrence of the specified element - * in this list, or -1 if this list does not contain the element. - * More formally, returns the highest index {@code i} such that - * (o==null ? get(i)==null : o.equals(get(i))), - * or -1 if there is no such index. - * - * @param o element to search for - * @return the index of the last occurrence of the specified element in - * this list, or -1 if this list does not contain the element - */ - public int lastIndexOf(Object o) { - int index = size; - if (o == null) { - for (Node x = last; x != null; x = x.prev) { - index--; - if (x.item == null) - return index; - } - } else { - for (Node x = last; x != null; x = x.prev) { - index--; - if (o.equals(x.item)) - return index; - } - } - return -1; - } - - // Queue operations. - - /** - * Retrieves, but does not remove, the head (first element) of this list. - * - * @return the head of this list, or {@code null} if this list is empty - * @since 1.5 - */ - public E peek() { - final Node f = first; - return (f == null) ? null : f.item; - } - - /** - * Retrieves, but does not remove, the head (first element) of this list. - * - * @return the head of this list - * @throws NoSuchElementException if this list is empty - * @since 1.5 - */ - public E element() { - return getFirst(); - } - - /** - * Retrieves and removes the head (first element) of this list. - * - * @return the head of this list, or {@code null} if this list is empty - * @since 1.5 - */ - public E poll() { - final Node f = first; - return (f == null) ? null : unlinkFirst(f); - } - - /** - * Retrieves and removes the head (first element) of this list. - * - * @return the head of this list - * @throws NoSuchElementException if this list is empty - * @since 1.5 - */ - public E remove() { - return removeFirst(); - } - - /** - * Adds the specified element as the tail (last element) of this list. - * - * @param e the element to add - * @return {@code true} (as specified by {@link Queue#offer}) - * @since 1.5 - */ - public boolean offer(E e) { - return add(e); - } - - // Deque operations - /** - * Inserts the specified element at the front of this list. - * - * @param e the element to insert - * @return {@code true} (as specified by {@link Deque#offerFirst}) - * @since 1.6 - */ - public boolean offerFirst(E e) { - addFirst(e); - return true; - } - - /** - * Inserts the specified element at the end of this list. - * - * @param e the element to insert - * @return {@code true} (as specified by {@link Deque#offerLast}) - * @since 1.6 - */ - public boolean offerLast(E e) { - addLast(e); - return true; - } - - /** - * Retrieves, but does not remove, the first element of this list, - * or returns {@code null} if this list is empty. - * - * @return the first element of this list, or {@code null} - * if this list is empty - * @since 1.6 - */ - public E peekFirst() { - final Node f = first; - return (f == null) ? null : f.item; - } - - /** - * Retrieves, but does not remove, the last element of this list, - * or returns {@code null} if this list is empty. - * - * @return the last element of this list, or {@code null} - * if this list is empty - * @since 1.6 - */ - public E peekLast() { - final Node l = last; - return (l == null) ? null : l.item; - } - - /** - * Retrieves and removes the first element of this list, - * or returns {@code null} if this list is empty. - * - * @return the first element of this list, or {@code null} if - * this list is empty - * @since 1.6 - */ - public E pollFirst() { - final Node f = first; - return (f == null) ? null : unlinkFirst(f); - } - - /** - * Retrieves and removes the last element of this list, - * or returns {@code null} if this list is empty. - * - * @return the last element of this list, or {@code null} if - * this list is empty - * @since 1.6 - */ - public E pollLast() { - final Node l = last; - return (l == null) ? null : unlinkLast(l); - } - - /** - * Pushes an element onto the stack represented by this list. In other - * words, inserts the element at the front of this list. - * - *

This method is equivalent to {@link #addFirst}. - * - * @param e the element to push - * @since 1.6 - */ - public void push(E e) { - addFirst(e); - } - - /** - * Pops an element from the stack represented by this list. In other - * words, removes and returns the first element of this list. - * - *

This method is equivalent to {@link #removeFirst()}. - * - * @return the element at the front of this list (which is the top - * of the stack represented by this list) - * @throws NoSuchElementException if this list is empty - * @since 1.6 - */ - public E pop() { - return removeFirst(); - } - - /** - * Removes the first occurrence of the specified element in this - * list (when traversing the list from head to tail). If the list - * does not contain the element, it is unchanged. - * - * @param o element to be removed from this list, if present - * @return {@code true} if the list contained the specified element - * @since 1.6 - */ - public boolean removeFirstOccurrence(Object o) { - return remove(o); - } - - /** - * Removes the last occurrence of the specified element in this - * list (when traversing the list from head to tail). If the list - * does not contain the element, it is unchanged. - * - * @param o element to be removed from this list, if present - * @return {@code true} if the list contained the specified element - * @since 1.6 - */ - public boolean removeLastOccurrence(Object o) { - if (o == null) { - for (Node x = last; x != null; x = x.prev) { - if (x.item == null) { - unlink(x); - return true; - } - } - } else { - for (Node x = last; x != null; x = x.prev) { - if (o.equals(x.item)) { - unlink(x); - return true; - } - } - } - return false; - } - - /** - * Returns a list-iterator of the elements in this list (in proper - * sequence), starting at the specified position in the list. - * Obeys the general contract of {@code List.listIterator(int)}.

- * - * The list-iterator is fail-fast: if the list is structurally - * modified at any time after the Iterator is created, in any way except - * through the list-iterator's own {@code remove} or {@code add} - * methods, the list-iterator will throw a - * {@code ConcurrentModificationException}. Thus, in the face of - * concurrent modification, the iterator fails quickly and cleanly, rather - * than risking arbitrary, non-deterministic behavior at an undetermined - * time in the future. - * - * @param index index of the first element to be returned from the - * list-iterator (by a call to {@code next}) - * @return a ListIterator of the elements in this list (in proper - * sequence), starting at the specified position in the list - * @throws IndexOutOfBoundsException {@inheritDoc} - * @see List#listIterator(int) - */ - public ListIterator listIterator(int index) { - checkPositionIndex(index); - return new ListItr(index); - } - - private class ListItr implements ListIterator { - private Node lastReturned = null; - private Node next; - private int nextIndex; - private int expectedModCount = modCount; - - ListItr(int index) { - // assert isPositionIndex(index); - next = (index == size) ? null : node(index); - nextIndex = index; - } - - public boolean hasNext() { - return nextIndex < size; - } - - public E next() { - checkForComodification(); - if (!hasNext()) - throw new NoSuchElementException(); - - lastReturned = next; - next = next.next; - nextIndex++; - return lastReturned.item; - } - - public boolean hasPrevious() { - return nextIndex > 0; - } - - public E previous() { - checkForComodification(); - if (!hasPrevious()) - throw new NoSuchElementException(); - - lastReturned = next = (next == null) ? last : next.prev; - nextIndex--; - return lastReturned.item; - } - - public int nextIndex() { - return nextIndex; - } - - public int previousIndex() { - return nextIndex - 1; - } - - public void remove() { - checkForComodification(); - if (lastReturned == null) - throw new IllegalStateException(); - - Node lastNext = lastReturned.next; - unlink(lastReturned); - if (next == lastReturned) - next = lastNext; - else - nextIndex--; - lastReturned = null; - expectedModCount++; - } - - public void set(E e) { - if (lastReturned == null) - throw new IllegalStateException(); - checkForComodification(); - lastReturned.item = e; - } - - public void add(E e) { - checkForComodification(); - lastReturned = null; - if (next == null) - linkLast(e); - else - linkBefore(e, next); - nextIndex++; - expectedModCount++; - } - - final void checkForComodification() { - if (modCount != expectedModCount) - throw new ConcurrentModificationException(); - } - } - - private static class Node { - E item; - Node next; - Node prev; - - Node(Node prev, E element, Node next) { - this.item = element; - this.next = next; - this.prev = prev; - } - } - - /** - * @since 1.6 - */ - public Iterator descendingIterator() { - return new DescendingIterator(); - } - - /** - * Adapter to provide descending iterators via ListItr.previous - */ - private class DescendingIterator implements Iterator { - private final ListItr itr = new ListItr(size()); - public boolean hasNext() { - return itr.hasPrevious(); - } - public E next() { - return itr.previous(); - } - public void remove() { - itr.remove(); - } - } - - @SuppressWarnings("unchecked") - private LinkedList superClone() { - try { - return (LinkedList) super.clone(); - } catch (CloneNotSupportedException e) { - throw new InternalError(); - } - } - - /** - * Returns a shallow copy of this {@code LinkedList}. (The elements - * themselves are not cloned.) - * - * @return a shallow copy of this {@code LinkedList} instance - */ - public Object clone() { - LinkedList clone = superClone(); - - // Put clone into "virgin" state - clone.first = clone.last = null; - clone.size = 0; - clone.modCount = 0; - - // Initialize clone with our elements - for (Node x = first; x != null; x = x.next) - clone.add(x.item); - - return clone; - } - - /** - * Returns an array containing all of the elements in this list - * in proper sequence (from first to last element). - * - *

The returned array will be "safe" in that no references to it are - * maintained by this list. (In other words, this method must allocate - * a new array). The caller is thus free to modify the returned array. - * - *

This method acts as bridge between array-based and collection-based - * APIs. - * - * @return an array containing all of the elements in this list - * in proper sequence - */ - public Object[] toArray() { - Object[] result = new Object[size]; - int i = 0; - for (Node x = first; x != null; x = x.next) - result[i++] = x.item; - return result; - } - - /** - * Returns an array containing all of the elements in this list in - * proper sequence (from first to last element); the runtime type of - * the returned array is that of the specified array. If the list fits - * in the specified array, it is returned therein. Otherwise, a new - * array is allocated with the runtime type of the specified array and - * the size of this list. - * - *

If the list fits in the specified array with room to spare (i.e., - * the array has more elements than the list), the element in the array - * immediately following the end of the list is set to {@code null}. - * (This is useful in determining the length of the list only if - * the caller knows that the list does not contain any null elements.) - * - *

Like the {@link #toArray()} method, this method acts as bridge between - * array-based and collection-based APIs. Further, this method allows - * precise control over the runtime type of the output array, and may, - * under certain circumstances, be used to save allocation costs. - * - *

Suppose {@code x} is a list known to contain only strings. - * The following code can be used to dump the list into a newly - * allocated array of {@code String}: - * - * 

-     *     String[] y = x.toArray(new String[0]);
- * - * Note that {@code toArray(new Object[0])} is identical in function to - * {@code toArray()}. - * - * @param a the array into which the elements of the list are to - * be stored, if it is big enough; otherwise, a new array of the - * same runtime type is allocated for this purpose. - * @return an array containing the elements of the list - * @throws ArrayStoreException if the runtime type of the specified array - * is not a supertype of the runtime type of every element in - * this list - * @throws NullPointerException if the specified array is null - */ - @SuppressWarnings("unchecked") - public T[] toArray(T[] a) { - if (a.length < size) - a = (T[])java.lang.reflect.Array.newInstance( - a.getClass().getComponentType(), size); - int i = 0; - Object[] result = a; - for (Node x = first; x != null; x = x.next) - result[i++] = x.item; - - if (a.length > size) - a[size] = null; - - return a; - } - - private static final long serialVersionUID = 876323262645176354L; - -}