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dl |
1.1 |
/* |
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jsr166 |
1.24 |
* Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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dl |
1.1 |
* |
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jsr166 |
1.24 |
* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Sun designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Sun in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
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* CA 95054 USA or visit www.sun.com if you need additional information or |
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* have any questions. |
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dl |
1.1 |
*/ |
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package java.util; |
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/** |
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* Resizable-array implementation of the <tt>List</tt> interface. Implements |
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* all optional list operations, and permits all elements, including |
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* <tt>null</tt>. In addition to implementing the <tt>List</tt> interface, |
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* this class provides methods to manipulate the size of the array that is |
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* used internally to store the list. (This class is roughly equivalent to |
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* <tt>Vector</tt>, except that it is unsynchronized.)<p> |
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* |
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* The <tt>size</tt>, <tt>isEmpty</tt>, <tt>get</tt>, <tt>set</tt>, |
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* <tt>iterator</tt>, and <tt>listIterator</tt> operations run in constant |
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* time. The <tt>add</tt> operation runs in <i>amortized constant time</i>, |
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* that is, adding n elements requires O(n) time. All of the other operations |
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* run in linear time (roughly speaking). The constant factor is low compared |
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* to that for the <tt>LinkedList</tt> implementation.<p> |
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* |
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* Each <tt>ArrayList</tt> instance has a <i>capacity</i>. The capacity is |
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* the size of the array used to store the elements in the list. It is always |
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* at least as large as the list size. As elements are added to an ArrayList, |
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* its capacity grows automatically. The details of the growth policy are not |
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* specified beyond the fact that adding an element has constant amortized |
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* time cost.<p> |
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* |
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* An application can increase the capacity of an <tt>ArrayList</tt> instance |
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* before adding a large number of elements using the <tt>ensureCapacity</tt> |
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* operation. This may reduce the amount of incremental reallocation. |
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* |
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* <p><strong>Note that this implementation is not synchronized.</strong> |
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* If multiple threads access an <tt>ArrayList</tt> instance concurrently, |
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* and at least one of the threads modifies the list structurally, it |
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* <i>must</i> be synchronized externally. (A structural modification is |
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* any operation that adds or deletes one or more elements, or explicitly |
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* resizes the backing array; merely setting the value of an element is not |
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* a structural modification.) This is typically accomplished by |
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* synchronizing on some object that naturally encapsulates the list. |
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* |
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* If no such object exists, the list should be "wrapped" using the |
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* {@link Collections#synchronizedList Collections.synchronizedList} |
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* method. This is best done at creation time, to prevent accidental |
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* unsynchronized access to the list:<pre> |
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* List list = Collections.synchronizedList(new ArrayList(...));</pre> |
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* |
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* <p>The iterators returned by this class's <tt>iterator</tt> and |
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* <tt>listIterator</tt> methods are <i>fail-fast</i>: if the list is |
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* structurally modified at any time after the iterator is created, in any way |
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* except through the iterator's own <tt>remove</tt> or <tt>add</tt> methods, |
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* the iterator will throw a {@link ConcurrentModificationException}. Thus, in |
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* the face of concurrent modification, the iterator fails quickly and cleanly, |
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* rather than risking arbitrary, non-deterministic behavior at an undetermined |
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* time in the future.<p> |
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* |
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* Note that the fail-fast behavior of an iterator cannot be guaranteed |
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* as it is, generally speaking, impossible to make any hard guarantees in the |
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* presence of unsynchronized concurrent modification. Fail-fast iterators |
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* throw <tt>ConcurrentModificationException</tt> on a best-effort basis. |
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* Therefore, it would be wrong to write a program that depended on this |
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* exception for its correctness: <i>the fail-fast behavior of iterators |
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* should be used only to detect bugs.</i><p> |
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* |
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* This class is a member of the |
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jsr166 |
1.21 |
* <a href="{@docRoot}/../technotes/guides/collections/index.html"> |
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dl |
1.1 |
* Java Collections Framework</a>. |
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* |
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* @author Josh Bloch |
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* @author Neal Gafter |
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jsr166 |
1.20 |
* @version %I%, %G% |
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1.1 |
* @see Collection |
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* @see List |
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* @see LinkedList |
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* @see Vector |
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* @since 1.2 |
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*/ |
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public class ArrayList<E> extends AbstractList<E> |
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implements List<E>, RandomAccess, Cloneable, java.io.Serializable |
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{ |
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private static final long serialVersionUID = 8683452581122892189L; |
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/** |
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* The array buffer into which the elements of the ArrayList are stored. |
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* The capacity of the ArrayList is the length of this array buffer. |
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*/ |
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private transient Object[] elementData; |
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/** |
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* The size of the ArrayList (the number of elements it contains). |
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* |
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* @serial |
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*/ |
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private int size; |
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/** |
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* Constructs an empty list with the specified initial capacity. |
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* |
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jsr166 |
1.5 |
* @param initialCapacity the initial capacity of the list |
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* @throws IllegalArgumentException if the specified initial capacity |
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* is negative |
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dl |
1.1 |
*/ |
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public ArrayList(int initialCapacity) { |
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super(); |
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if (initialCapacity < 0) |
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throw new IllegalArgumentException("Illegal Capacity: "+ |
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initialCapacity); |
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this.elementData = new Object[initialCapacity]; |
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} |
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/** |
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* Constructs an empty list with an initial capacity of ten. |
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*/ |
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public ArrayList() { |
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this(10); |
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} |
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/** |
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* Constructs a list containing the elements of the specified |
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* collection, in the order they are returned by the collection's |
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jsr166 |
1.17 |
* iterator. |
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dl |
1.1 |
* |
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* @param c the collection whose elements are to be placed into this list |
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* @throws NullPointerException if the specified collection is null |
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*/ |
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public ArrayList(Collection<? extends E> c) { |
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dl |
1.2 |
elementData = c.toArray(); |
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size = elementData.length; |
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// c.toArray might (incorrectly) not return Object[] (see 6260652) |
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if (elementData.getClass() != Object[].class) |
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elementData = Arrays.copyOf(elementData, size, Object[].class); |
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} |
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jsr166 |
1.4 |
|
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dl |
1.1 |
/** |
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* Trims the capacity of this <tt>ArrayList</tt> instance to be the |
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* list's current size. An application can use this operation to minimize |
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* the storage of an <tt>ArrayList</tt> instance. |
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*/ |
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public void trimToSize() { |
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modCount++; |
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int oldCapacity = elementData.length; |
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if (size < oldCapacity) { |
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elementData = Arrays.copyOf(elementData, size); |
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} |
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} |
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/** |
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* Increases the capacity of this <tt>ArrayList</tt> instance, if |
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* necessary, to ensure that it can hold at least the number of elements |
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* specified by the minimum capacity argument. |
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* |
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jsr166 |
1.5 |
* @param minCapacity the desired minimum capacity |
175 |
dl |
1.1 |
*/ |
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public void ensureCapacity(int minCapacity) { |
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modCount++; |
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if (minCapacity > elementData.length) |
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growArray(minCapacity); |
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} |
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/** |
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jsr166 |
1.5 |
* Increases the capacity of the array. |
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* |
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* @param minCapacity the desired minimum capacity |
186 |
dl |
1.1 |
*/ |
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private void growArray(int minCapacity) { |
188 |
jsr166 |
1.18 |
if (minCapacity < 0) // overflow |
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throw new OutOfMemoryError(); |
190 |
dl |
1.1 |
int oldCapacity = elementData.length; |
191 |
dl |
1.19 |
// Double size if small; else grow by 50% |
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int newCapacity = ((oldCapacity < 64) ? |
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((oldCapacity + 1) * 2) : |
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((oldCapacity / 2) * 3)); |
195 |
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if (newCapacity < 0) // overflow |
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newCapacity = Integer.MAX_VALUE; |
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if (newCapacity < minCapacity) |
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newCapacity = minCapacity; |
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elementData = Arrays.copyOf(elementData, newCapacity); |
200 |
dl |
1.1 |
} |
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/** |
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* Returns the number of elements in this list. |
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* |
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* @return the number of elements in this list |
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*/ |
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public int size() { |
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return size; |
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} |
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/** |
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* Returns <tt>true</tt> if this list contains no elements. |
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* |
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* @return <tt>true</tt> if this list contains no elements |
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*/ |
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public boolean isEmpty() { |
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return size == 0; |
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} |
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/** |
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* Returns <tt>true</tt> if this list contains the specified element. |
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* More formally, returns <tt>true</tt> if and only if this list contains |
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* at least one element <tt>e</tt> such that |
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* <tt>(o==null ? e==null : o.equals(e))</tt>. |
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* |
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* @param o element whose presence in this list is to be tested |
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* @return <tt>true</tt> if this list contains the specified element |
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*/ |
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public boolean contains(Object o) { |
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return indexOf(o) >= 0; |
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} |
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/** |
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* Returns the index of the first occurrence of the specified element |
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* in this list, or -1 if this list does not contain the element. |
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* More formally, returns the lowest index <tt>i</tt> such that |
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* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
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* or -1 if there is no such index. |
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*/ |
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public int indexOf(Object o) { |
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if (o == null) { |
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for (int i = 0; i < size; i++) |
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if (elementData[i]==null) |
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return i; |
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} else { |
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for (int i = 0; i < size; i++) |
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if (o.equals(elementData[i])) |
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return i; |
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} |
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return -1; |
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} |
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/** |
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* Returns the index of the last occurrence of the specified element |
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* in this list, or -1 if this list does not contain the element. |
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* More formally, returns the highest index <tt>i</tt> such that |
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* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
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* or -1 if there is no such index. |
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*/ |
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public int lastIndexOf(Object o) { |
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if (o == null) { |
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for (int i = size-1; i >= 0; i--) |
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if (elementData[i]==null) |
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return i; |
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} else { |
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for (int i = size-1; i >= 0; i--) |
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if (o.equals(elementData[i])) |
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return i; |
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} |
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return -1; |
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} |
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273 |
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/** |
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* Returns a shallow copy of this <tt>ArrayList</tt> instance. (The |
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* elements themselves are not copied.) |
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* |
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* @return a clone of this <tt>ArrayList</tt> instance |
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*/ |
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public Object clone() { |
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try { |
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ArrayList<E> v = (ArrayList<E>) super.clone(); |
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v.elementData = Arrays.copyOf(elementData, size); |
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v.modCount = 0; |
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return v; |
285 |
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} catch (CloneNotSupportedException e) { |
286 |
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// this shouldn't happen, since we are Cloneable |
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throw new InternalError(); |
288 |
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} |
289 |
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} |
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291 |
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/** |
292 |
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* Returns an array containing all of the elements in this list |
293 |
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* in proper sequence (from first to last element). |
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* |
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* <p>The returned array will be "safe" in that no references to it are |
296 |
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* maintained by this list. (In other words, this method must allocate |
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* a new array). The caller is thus free to modify the returned array. |
298 |
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* |
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* <p>This method acts as bridge between array-based and collection-based |
300 |
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* APIs. |
301 |
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* |
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* @return an array containing all of the elements in this list in |
303 |
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* proper sequence |
304 |
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*/ |
305 |
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public Object[] toArray() { |
306 |
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return Arrays.copyOf(elementData, size); |
307 |
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} |
308 |
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|
309 |
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/** |
310 |
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* Returns an array containing all of the elements in this list in proper |
311 |
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* sequence (from first to last element); the runtime type of the returned |
312 |
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* array is that of the specified array. If the list fits in the |
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* specified array, it is returned therein. Otherwise, a new array is |
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* allocated with the runtime type of the specified array and the size of |
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* this list. |
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* |
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* <p>If the list fits in the specified array with room to spare |
318 |
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* (i.e., the array has more elements than the list), the element in |
319 |
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* the array immediately following the end of the collection is set to |
320 |
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* <tt>null</tt>. (This is useful in determining the length of the |
321 |
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* list <i>only</i> if the caller knows that the list does not contain |
322 |
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* any null elements.) |
323 |
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* |
324 |
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* @param a the array into which the elements of the list are to |
325 |
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* be stored, if it is big enough; otherwise, a new array of the |
326 |
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* same runtime type is allocated for this purpose. |
327 |
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* @return an array containing the elements of the list |
328 |
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* @throws ArrayStoreException if the runtime type of the specified array |
329 |
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* is not a supertype of the runtime type of every element in |
330 |
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* this list |
331 |
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* @throws NullPointerException if the specified array is null |
332 |
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*/ |
333 |
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public <T> T[] toArray(T[] a) { |
334 |
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if (a.length < size) |
335 |
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// Make a new array of a's runtime type, but my contents: |
336 |
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return (T[]) Arrays.copyOf(elementData, size, a.getClass()); |
337 |
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System.arraycopy(elementData, 0, a, 0, size); |
338 |
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if (a.length > size) |
339 |
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a[size] = null; |
340 |
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return a; |
341 |
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} |
342 |
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|
343 |
|
|
// Positional Access Operations |
344 |
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|
345 |
jsr166 |
1.4 |
/** |
346 |
dl |
1.19 |
* Throws an appropriate exception for indexing errors. |
347 |
dl |
1.1 |
*/ |
348 |
dl |
1.19 |
private static void indexOutOfBounds(int i, int s) { |
349 |
|
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throw new IndexOutOfBoundsException("Index: " + i + ", Size: " + s); |
350 |
dl |
1.1 |
} |
351 |
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|
352 |
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/** |
353 |
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* Returns the element at the specified position in this list. |
354 |
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* |
355 |
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* @param index index of the element to return |
356 |
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* @return the element at the specified position in this list |
357 |
|
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* @throws IndexOutOfBoundsException {@inheritDoc} |
358 |
|
|
*/ |
359 |
|
|
public E get(int index) { |
360 |
|
|
if (index >= size) |
361 |
dl |
1.19 |
indexOutOfBounds(index, size); |
362 |
|
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return (E) elementData[index]; |
363 |
dl |
1.1 |
} |
364 |
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|
365 |
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/** |
366 |
|
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* Replaces the element at the specified position in this list with |
367 |
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* the specified element. |
368 |
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* |
369 |
|
|
* @param index index of the element to replace |
370 |
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* @param element element to be stored at the specified position |
371 |
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* @return the element previously at the specified position |
372 |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
373 |
|
|
*/ |
374 |
|
|
public E set(int index, E element) { |
375 |
|
|
if (index >= size) |
376 |
dl |
1.19 |
indexOutOfBounds(index, size); |
377 |
dl |
1.1 |
E oldValue = (E) elementData[index]; |
378 |
|
|
elementData[index] = element; |
379 |
|
|
return oldValue; |
380 |
|
|
} |
381 |
|
|
|
382 |
|
|
/** |
383 |
|
|
* Appends the specified element to the end of this list. |
384 |
|
|
* |
385 |
|
|
* @param e element to be appended to this list |
386 |
|
|
* @return <tt>true</tt> (as specified by {@link Collection#add}) |
387 |
|
|
*/ |
388 |
|
|
public boolean add(E e) { |
389 |
jsr166 |
1.8 |
modCount++; |
390 |
dl |
1.7 |
int s = size; |
391 |
dl |
1.1 |
if (s >= elementData.length) |
392 |
|
|
growArray(s + 1); |
393 |
|
|
elementData[s] = e; |
394 |
dl |
1.19 |
size = s + 1; |
395 |
|
|
return true; |
396 |
dl |
1.1 |
} |
397 |
|
|
|
398 |
|
|
/** |
399 |
|
|
* Inserts the specified element at the specified position in this |
400 |
|
|
* list. Shifts the element currently at that position (if any) and |
401 |
|
|
* any subsequent elements to the right (adds one to their indices). |
402 |
|
|
* |
403 |
|
|
* @param index index at which the specified element is to be inserted |
404 |
|
|
* @param element element to be inserted |
405 |
|
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
406 |
|
|
*/ |
407 |
|
|
public void add(int index, E element) { |
408 |
|
|
int s = size; |
409 |
|
|
if (index > s || index < 0) |
410 |
dl |
1.19 |
indexOutOfBounds(index, s); |
411 |
jsr166 |
1.8 |
modCount++; |
412 |
dl |
1.1 |
if (s >= elementData.length) |
413 |
|
|
growArray(s + 1); |
414 |
jsr166 |
1.10 |
System.arraycopy(elementData, index, |
415 |
dl |
1.19 |
elementData, index + 1, s - index); |
416 |
dl |
1.1 |
elementData[index] = element; |
417 |
dl |
1.7 |
size = s + 1; |
418 |
dl |
1.1 |
} |
419 |
|
|
|
420 |
|
|
/** |
421 |
|
|
* Removes the element at the specified position in this list. |
422 |
|
|
* Shifts any subsequent elements to the left (subtracts one from their |
423 |
|
|
* indices). |
424 |
|
|
* |
425 |
|
|
* @param index the index of the element to be removed |
426 |
|
|
* @return the element that was removed from the list |
427 |
|
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
428 |
|
|
*/ |
429 |
|
|
public E remove(int index) { |
430 |
|
|
int s = size - 1; |
431 |
jsr166 |
1.8 |
if (index > s) |
432 |
dl |
1.19 |
indexOutOfBounds(index, size); |
433 |
dl |
1.1 |
modCount++; |
434 |
dl |
1.19 |
E oldValue = (E) elementData[index]; |
435 |
dl |
1.1 |
int numMoved = s - index; |
436 |
|
|
if (numMoved > 0) |
437 |
jsr166 |
1.10 |
System.arraycopy(elementData, index + 1, |
438 |
dl |
1.19 |
elementData, index, numMoved); |
439 |
jsr166 |
1.8 |
elementData[s] = null; |
440 |
dl |
1.19 |
size = s; |
441 |
dl |
1.7 |
return oldValue; |
442 |
dl |
1.1 |
} |
443 |
|
|
|
444 |
|
|
/** |
445 |
|
|
* Removes the first occurrence of the specified element from this list, |
446 |
|
|
* if it is present. If the list does not contain the element, it is |
447 |
|
|
* unchanged. More formally, removes the element with the lowest index |
448 |
|
|
* <tt>i</tt> such that |
449 |
|
|
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt> |
450 |
|
|
* (if such an element exists). Returns <tt>true</tt> if this list |
451 |
|
|
* contained the specified element (or equivalently, if this list |
452 |
|
|
* changed as a result of the call). |
453 |
|
|
* |
454 |
|
|
* @param o element to be removed from this list, if present |
455 |
|
|
* @return <tt>true</tt> if this list contained the specified element |
456 |
|
|
*/ |
457 |
|
|
public boolean remove(Object o) { |
458 |
|
|
if (o == null) { |
459 |
|
|
for (int index = 0; index < size; index++) |
460 |
|
|
if (elementData[index] == null) { |
461 |
|
|
fastRemove(index); |
462 |
|
|
return true; |
463 |
|
|
} |
464 |
|
|
} else { |
465 |
|
|
for (int index = 0; index < size; index++) |
466 |
|
|
if (o.equals(elementData[index])) { |
467 |
|
|
fastRemove(index); |
468 |
|
|
return true; |
469 |
|
|
} |
470 |
|
|
} |
471 |
|
|
return false; |
472 |
|
|
} |
473 |
|
|
|
474 |
|
|
/* |
475 |
|
|
* Private remove method that skips bounds checking and does not |
476 |
|
|
* return the value removed. |
477 |
|
|
*/ |
478 |
|
|
private void fastRemove(int index) { |
479 |
|
|
modCount++; |
480 |
|
|
int numMoved = size - index - 1; |
481 |
|
|
if (numMoved > 0) |
482 |
|
|
System.arraycopy(elementData, index+1, elementData, index, |
483 |
|
|
numMoved); |
484 |
|
|
elementData[--size] = null; // Let gc do its work |
485 |
|
|
} |
486 |
|
|
|
487 |
|
|
/** |
488 |
|
|
* Removes all of the elements from this list. The list will |
489 |
|
|
* be empty after this call returns. |
490 |
|
|
*/ |
491 |
|
|
public void clear() { |
492 |
|
|
modCount++; |
493 |
|
|
|
494 |
|
|
// Let gc do its work |
495 |
|
|
for (int i = 0; i < size; i++) |
496 |
|
|
elementData[i] = null; |
497 |
|
|
|
498 |
|
|
size = 0; |
499 |
|
|
} |
500 |
|
|
|
501 |
|
|
/** |
502 |
|
|
* Appends all of the elements in the specified collection to the end of |
503 |
|
|
* this list, in the order that they are returned by the |
504 |
|
|
* specified collection's Iterator. The behavior of this operation is |
505 |
|
|
* undefined if the specified collection is modified while the operation |
506 |
|
|
* is in progress. (This implies that the behavior of this call is |
507 |
|
|
* undefined if the specified collection is this list, and this |
508 |
|
|
* list is nonempty.) |
509 |
|
|
* |
510 |
|
|
* @param c collection containing elements to be added to this list |
511 |
|
|
* @return <tt>true</tt> if this list changed as a result of the call |
512 |
|
|
* @throws NullPointerException if the specified collection is null |
513 |
|
|
*/ |
514 |
|
|
public boolean addAll(Collection<? extends E> c) { |
515 |
|
|
Object[] a = c.toArray(); |
516 |
|
|
int numNew = a.length; |
517 |
|
|
ensureCapacity(size + numNew); // Increments modCount |
518 |
|
|
System.arraycopy(a, 0, elementData, size, numNew); |
519 |
|
|
size += numNew; |
520 |
|
|
return numNew != 0; |
521 |
|
|
} |
522 |
|
|
|
523 |
|
|
/** |
524 |
|
|
* Inserts all of the elements in the specified collection into this |
525 |
|
|
* list, starting at the specified position. Shifts the element |
526 |
|
|
* currently at that position (if any) and any subsequent elements to |
527 |
|
|
* the right (increases their indices). The new elements will appear |
528 |
|
|
* in the list in the order that they are returned by the |
529 |
|
|
* specified collection's iterator. |
530 |
|
|
* |
531 |
|
|
* @param index index at which to insert the first element from the |
532 |
|
|
* specified collection |
533 |
|
|
* @param c collection containing elements to be added to this list |
534 |
|
|
* @return <tt>true</tt> if this list changed as a result of the call |
535 |
|
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
536 |
|
|
* @throws NullPointerException if the specified collection is null |
537 |
|
|
*/ |
538 |
|
|
public boolean addAll(int index, Collection<? extends E> c) { |
539 |
|
|
if (index > size || index < 0) |
540 |
dl |
1.19 |
indexOutOfBounds(index, size); |
541 |
dl |
1.1 |
|
542 |
|
|
Object[] a = c.toArray(); |
543 |
|
|
int numNew = a.length; |
544 |
|
|
ensureCapacity(size + numNew); // Increments modCount |
545 |
|
|
|
546 |
|
|
int numMoved = size - index; |
547 |
|
|
if (numMoved > 0) |
548 |
|
|
System.arraycopy(elementData, index, elementData, index + numNew, |
549 |
|
|
numMoved); |
550 |
|
|
|
551 |
|
|
System.arraycopy(a, 0, elementData, index, numNew); |
552 |
|
|
size += numNew; |
553 |
|
|
return numNew != 0; |
554 |
|
|
} |
555 |
|
|
|
556 |
|
|
/** |
557 |
|
|
* Removes from this list all of the elements whose index is between |
558 |
|
|
* <tt>fromIndex</tt>, inclusive, and <tt>toIndex</tt>, exclusive. |
559 |
|
|
* Shifts any succeeding elements to the left (reduces their index). |
560 |
|
|
* This call shortens the list by <tt>(toIndex - fromIndex)</tt> elements. |
561 |
|
|
* (If <tt>toIndex==fromIndex</tt>, this operation has no effect.) |
562 |
|
|
* |
563 |
|
|
* @param fromIndex index of first element to be removed |
564 |
|
|
* @param toIndex index after last element to be removed |
565 |
|
|
* @throws IndexOutOfBoundsException if fromIndex or toIndex out of |
566 |
|
|
* range (fromIndex < 0 || fromIndex >= size() || toIndex |
567 |
|
|
* > size() || toIndex < fromIndex) |
568 |
|
|
*/ |
569 |
|
|
protected void removeRange(int fromIndex, int toIndex) { |
570 |
|
|
modCount++; |
571 |
|
|
int numMoved = size - toIndex; |
572 |
|
|
System.arraycopy(elementData, toIndex, elementData, fromIndex, |
573 |
|
|
numMoved); |
574 |
|
|
|
575 |
|
|
// Let gc do its work |
576 |
|
|
int newSize = size - (toIndex-fromIndex); |
577 |
|
|
while (size != newSize) |
578 |
|
|
elementData[--size] = null; |
579 |
|
|
} |
580 |
|
|
|
581 |
|
|
/** |
582 |
|
|
* Save the state of the <tt>ArrayList</tt> instance to a stream (that |
583 |
|
|
* is, serialize it). |
584 |
|
|
* |
585 |
|
|
* @serialData The length of the array backing the <tt>ArrayList</tt> |
586 |
|
|
* instance is emitted (int), followed by all of its elements |
587 |
|
|
* (each an <tt>Object</tt>) in the proper order. |
588 |
|
|
*/ |
589 |
|
|
private void writeObject(java.io.ObjectOutputStream s) |
590 |
|
|
throws java.io.IOException{ |
591 |
|
|
// Write out element count, and any hidden stuff |
592 |
|
|
int expectedModCount = modCount; |
593 |
|
|
s.defaultWriteObject(); |
594 |
|
|
|
595 |
|
|
// Write out array length |
596 |
|
|
s.writeInt(elementData.length); |
597 |
|
|
|
598 |
|
|
// Write out all elements in the proper order. |
599 |
|
|
for (int i=0; i<size; i++) |
600 |
|
|
s.writeObject(elementData[i]); |
601 |
|
|
|
602 |
jsr166 |
1.12 |
if (expectedModCount != modCount) { |
603 |
dl |
1.1 |
throw new ConcurrentModificationException(); |
604 |
|
|
} |
605 |
|
|
|
606 |
|
|
} |
607 |
|
|
|
608 |
|
|
/** |
609 |
|
|
* Reconstitute the <tt>ArrayList</tt> instance from a stream (that is, |
610 |
|
|
* deserialize it). |
611 |
|
|
*/ |
612 |
|
|
private void readObject(java.io.ObjectInputStream s) |
613 |
|
|
throws java.io.IOException, ClassNotFoundException { |
614 |
|
|
// Read in size, and any hidden stuff |
615 |
|
|
s.defaultReadObject(); |
616 |
|
|
|
617 |
|
|
// Read in array length and allocate array |
618 |
|
|
int arrayLength = s.readInt(); |
619 |
|
|
Object[] a = elementData = new Object[arrayLength]; |
620 |
|
|
|
621 |
|
|
// Read in all elements in the proper order. |
622 |
|
|
for (int i=0; i<size; i++) |
623 |
|
|
a[i] = s.readObject(); |
624 |
|
|
} |
625 |
|
|
} |