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*/ |
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package java.util; |
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import java.io.Serializable; |
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import java.util.function.Consumer; |
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import java.util.stream.Stream; |
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/** |
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* Resizable-array implementation of the {@link Deque} interface. Array |
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* |
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* @author Josh Bloch and Doug Lea |
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* @since 1.6 |
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* @param <E> the type of elements held in this collection |
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* @param <E> the type of elements held in this deque |
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*/ |
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public class ArrayDeque<E> extends AbstractCollection<E> |
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implements Deque<E>, Cloneable, Serializable |
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@SuppressWarnings("unchecked") |
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E result = (E) elements[h]; |
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// Element is null if deque empty |
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if (result == null) |
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return null; |
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elements[h] = null; // Must null out slot |
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head = (h + 1) & (elements.length - 1); |
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if (result != null) { |
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elements[h] = null; // Must null out slot |
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head = (h + 1) & (elements.length - 1); |
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} |
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return result; |
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} |
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int t = (tail - 1) & (elements.length - 1); |
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@SuppressWarnings("unchecked") |
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E result = (E) elements[t]; |
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if (result == null) |
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return null; |
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elements[t] = null; |
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tail = t; |
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if (result != null) { |
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elements[t] = null; |
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tail = t; |
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} |
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return result; |
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} |
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* @return {@code true} if the deque contained the specified element |
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*/ |
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public boolean removeFirstOccurrence(Object o) { |
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if (o == null) |
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return false; |
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int mask = elements.length - 1; |
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int i = head; |
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Object x; |
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while ( (x = elements[i]) != null) { |
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if (o.equals(x)) { |
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delete(i); |
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return true; |
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if (o != null) { |
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int mask = elements.length - 1; |
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int i = head; |
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for (Object x; (x = elements[i]) != null; i = (i + 1) & mask) { |
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if (o.equals(x)) { |
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delete(i); |
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return true; |
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} |
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} |
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i = (i + 1) & mask; |
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} |
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return false; |
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} |
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* @return {@code true} if the deque contained the specified element |
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*/ |
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public boolean removeLastOccurrence(Object o) { |
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if (o == null) |
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return false; |
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int mask = elements.length - 1; |
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int i = (tail - 1) & mask; |
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Object x; |
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while ( (x = elements[i]) != null) { |
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if (o.equals(x)) { |
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delete(i); |
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return true; |
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if (o != null) { |
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int mask = elements.length - 1; |
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int i = (tail - 1) & mask; |
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for (Object x; (x = elements[i]) != null; i = (i - 1) & mask) { |
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if (o.equals(x)) { |
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delete(i); |
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return true; |
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} |
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} |
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i = (i - 1) & mask; |
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} |
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return false; |
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} |
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* @return {@code true} if this deque contains the specified element |
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*/ |
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public boolean contains(Object o) { |
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if (o == null) |
658 |
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return false; |
659 |
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int mask = elements.length - 1; |
660 |
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int i = head; |
661 |
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Object x; |
662 |
< |
while ( (x = elements[i]) != null) { |
663 |
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if (o.equals(x)) |
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return true; |
669 |
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i = (i + 1) & mask; |
657 |
> |
if (o != null) { |
658 |
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int mask = elements.length - 1; |
659 |
> |
int i = head; |
660 |
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for (Object x; (x = elements[i]) != null; i = (i + 1) & mask) { |
661 |
> |
if (o.equals(x)) |
662 |
> |
return true; |
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} |
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} |
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return false; |
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} |
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* The following code can be used to dump the deque into a newly |
747 |
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* allocated array of {@code String}: |
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* |
749 |
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* <pre> {@code String[] y = x.toArray(new String[0]);}</pre> |
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* <pre> {@code String[] y = x.toArray(new String[0]);}</pre> |
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* |
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* Note that {@code toArray(new Object[0])} is identical in function to |
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* {@code toArray()}. |
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* Saves this deque to a stream (that is, serializes it). |
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* |
807 |
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* @param s the stream |
808 |
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* @throws java.io.IOException if an I/O error occurs |
809 |
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* @serialData The current size ({@code int}) of the deque, |
810 |
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* followed by all of its elements (each an object reference) in |
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* first-to-last order. |
826 |
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/** |
827 |
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* Reconstitutes this deque from a stream (that is, deserializes it). |
828 |
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* @param s the stream |
829 |
+ |
* @throws ClassNotFoundException if the class of a serialized object |
830 |
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* could not be found |
831 |
+ |
* @throws java.io.IOException if an I/O error occurs |
832 |
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*/ |
833 |
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private void readObject(java.io.ObjectInputStream s) |
834 |
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throws java.io.IOException, ClassNotFoundException { |
901 |
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throw new NullPointerException(); |
902 |
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Object[] a = deq.elements; |
903 |
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int m = a.length - 1, f = getFence(), i = index; |
904 |
< |
if (i != fence) { |
904 |
> |
if (i != f) { |
905 |
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@SuppressWarnings("unchecked") E e = (E)a[i]; |
906 |
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index = (i + 1) & m; |
907 |
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if (e == null) |