jgit/org.eclipse.jgit/src/org/eclipse/jgit/diff/Sequence.java

/*
 * Copyright (C) 2010, Google Inc.
 * Copyright (C) 2008-2009, Johannes E. Schindelin <johannes.schindelin@gmx.de>
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
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 * without modification, are permitted provided that the following
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package org.eclipse.jgit.diff;

/**
 * Arbitrary sequence of elements.
 * <p>
 * A sequence of elements is defined to contain elements in the index range
 * <code>[0, {@link #size()})</code>, like a standard Java List implementation.
 * Unlike a List, the members of the sequence are not directly obtainable.
 * <p>
 * Implementations of Sequence are primarily intended for use in content
 * difference detection algorithms, to produce an {@link EditList} of
 * {@link Edit} instances describing how two Sequence instances differ.
 * <p>
 * To be compared against another Sequence of the same type, a supporting
 * {@link SequenceComparator} must also be supplied.
 */
public abstract class Sequence {
	/** @return total number of items in the sequence. */
	public abstract int size();
}