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/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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package java.util;
/**
* Marker interface used by List implementations to indicate that
* they support fast (generally constant time) random access. The primary
* purpose of this interface is to allow generic algorithms to alter their
* behavior to provide good performance when applied to either random or
* sequential access lists.
*
* The best algorithms for manipulating random access lists (such as
* ArrayList) can produce quadratic behavior when applied to
* sequential access lists (such as LinkedList). Generic list
* algorithms are encouraged to check whether the given list is an
* instanceof this interface before applying an algorithm that would
* provide poor performance if it were applied to a sequential access list,
* and to alter their behavior if necessary to guarantee acceptable
* performance.
*
*
It is recognized that the distinction between random and sequential
* access is often fuzzy. For example, some List implementations
* provide asymptotically linear access times if they get huge, but constant
* access times in practice. Such a List implementation
* should generally implement this interface. As a rule of thumb, a
* List implementation should implement this interface if,
* for typical instances of the class, this loop:
*
* for (int i=0, n=list.size(); i < n; i++)
* list.get(i);
*
* runs faster than this loop:
*
* for (Iterator i=list.iterator(); i.hasNext(); )
* i.next();
*
*
* This interface is a member of the
*
* Java Collections Framework.
*
* @since 1.4
*/
public interface RandomAccess {
}