| /* |
| * Copyright (C) 2010, Google Inc. |
| * 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 |
| * |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or |
| * without modification, are permitted provided that the following |
| * conditions are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * - Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following |
| * disclaimer in the documentation and/or other materials provided |
| * with the distribution. |
| * |
| * - Neither the name of the Eclipse Foundation, Inc. nor the |
| * names of its contributors may be used to endorse or promote |
| * products derived from this software without specific prior |
| * written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
| * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
| * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| package org.eclipse.jgit.diff; |
| |
| /** |
| * Wraps a {@link Sequence} to have a narrower range of elements. |
| * <p> |
| * This sequence acts as a proxy for the real sequence, translating element |
| * indexes on the fly by adding {@code begin} to them. Sequences of this type |
| * must be used with a {@link SubsequenceComparator}. |
| * |
| * @param <S> |
| * the base sequence type. |
| */ |
| public final class Subsequence<S extends Sequence> extends Sequence { |
| /** |
| * Construct a subsequence around the A region/base sequence. |
| * |
| * @param <S> |
| * the base sequence type. |
| * @param a |
| * the A sequence. |
| * @param region |
| * the region of {@code a} to create a subsequence around. |
| * @return subsequence of {@code base} as described by A in {@code region}. |
| */ |
| public static <S extends Sequence> Subsequence<S> a(S a, Edit region) { |
| return new Subsequence<S>(a, region.beginA, region.endA); |
| } |
| |
| /** |
| * Construct a subsequence around the B region/base sequence. |
| * |
| * @param <S> |
| * the base sequence type. |
| * @param b |
| * the B sequence. |
| * @param region |
| * the region of {@code b} to create a subsequence around. |
| * @return subsequence of {@code base} as described by B in {@code region}. |
| */ |
| public static <S extends Sequence> Subsequence<S> b(S b, Edit region) { |
| return new Subsequence<S>(b, region.beginB, region.endB); |
| } |
| |
| /** |
| * Adjust the Edit to reflect positions in the base sequence. |
| * |
| * @param <S> |
| * the base sequence type. |
| * @param e |
| * edit to adjust in-place. Prior to invocation the indexes are |
| * in terms of the two subsequences; after invocation the indexes |
| * are in terms of the base sequences. |
| * @param a |
| * the A sequence. |
| * @param b |
| * the B sequence. |
| */ |
| public static <S extends Sequence> void toBase(Edit e, Subsequence<S> a, |
| Subsequence<S> b) { |
| e.beginA += a.begin; |
| e.endA += a.begin; |
| |
| e.beginB += b.begin; |
| e.endB += b.begin; |
| } |
| |
| /** |
| * Adjust the Edits to reflect positions in the base sequence. |
| * |
| * @param <S> |
| * the base sequence type. |
| * @param edits |
| * edits to adjust in-place. Prior to invocation the indexes are |
| * in terms of the two subsequences; after invocation the indexes |
| * are in terms of the base sequences. |
| * @param a |
| * the A sequence. |
| * @param b |
| * the B sequence. |
| * @return always {@code edits} (as the list was updated in-place). |
| */ |
| public static <S extends Sequence> EditList toBase(EditList edits, |
| Subsequence<S> a, Subsequence<S> b) { |
| for (Edit e : edits) |
| toBase(e, a, b); |
| return edits; |
| } |
| |
| final S base; |
| |
| final int begin; |
| |
| private final int size; |
| |
| /** |
| * Construct a subset of another sequence. |
| * |
| * The size of the subsequence will be {@code end - begin}. |
| * |
| * @param base |
| * the real sequence. |
| * @param begin |
| * First element index of {@code base} that will be part of this |
| * new subsequence. The element at {@code begin} will be this |
| * sequence's element 0. |
| * @param end |
| * One past the last element index of {@code base} that will be |
| * part of this new subsequence. |
| */ |
| public Subsequence(S base, int begin, int end) { |
| this.base = base; |
| this.begin = begin; |
| this.size = end - begin; |
| } |
| |
| @Override |
| public int size() { |
| return size; |
| } |
| } |