| /* |
| * 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 |
| * |
| * 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; |
| |
| /** |
| * A modified region detected between two versions of roughly the same content. |
| * <p> |
| * An edit covers the modified region only. It does not cover a common region. |
| * <p> |
| * Regions should be specified using 0 based notation, so add 1 to the start and |
| * end marks for line numbers in a file. |
| * <p> |
| * An edit where {@code beginA == endA && beginB < endB} is an insert edit, that |
| * is sequence B inserted the elements in region <code>[beginB, endB)</code> at |
| * <code>beginA</code>. |
| * <p> |
| * An edit where {@code beginA < endA && beginB == endB} is a delete edit, that |
| * is sequence B has removed the elements between <code>[beginA, endA)</code>. |
| * <p> |
| * An edit where {@code beginA < endA && beginB < endB} is a replace edit, that |
| * is sequence B has replaced the range of elements between |
| * <code>[beginA, endA)</code> with those found in <code>[beginB, endB)</code>. |
| */ |
| public class Edit { |
| /** Type of edit */ |
| public static enum Type { |
| /** Sequence B has inserted the region. */ |
| INSERT, |
| |
| /** Sequence B has removed the region. */ |
| DELETE, |
| |
| /** Sequence B has replaced the region with different content. */ |
| REPLACE, |
| |
| /** Sequence A and B have zero length, describing nothing. */ |
| EMPTY; |
| } |
| |
| int beginA; |
| |
| int endA; |
| |
| int beginB; |
| |
| int endB; |
| |
| /** |
| * Create a new empty edit. |
| * |
| * @param as |
| * beginA: start and end of region in sequence A; 0 based. |
| * @param bs |
| * beginB: start and end of region in sequence B; 0 based. |
| */ |
| public Edit(final int as, final int bs) { |
| this(as, as, bs, bs); |
| } |
| |
| /** |
| * Create a new edit. |
| * |
| * @param as |
| * beginA: start of region in sequence A; 0 based. |
| * @param ae |
| * endA: end of region in sequence A; must be >= as. |
| * @param bs |
| * beginB: start of region in sequence B; 0 based. |
| * @param be |
| * endB: end of region in sequence B; must be > = bs. |
| */ |
| public Edit(final int as, final int ae, final int bs, final int be) { |
| beginA = as; |
| endA = ae; |
| |
| beginB = bs; |
| endB = be; |
| } |
| |
| /** @return the type of this region */ |
| public final Type getType() { |
| if (beginA < endA) { |
| if (beginB < endB) |
| return Type.REPLACE; |
| else /* if (beginB == endB) */ |
| return Type.DELETE; |
| |
| } else /* if (beginA == endA) */{ |
| if (beginB < endB) |
| return Type.INSERT; |
| else /* if (beginB == endB) */ |
| return Type.EMPTY; |
| } |
| } |
| |
| /** @return true if the edit is empty (lengths of both a and b is zero). */ |
| public final boolean isEmpty() { |
| return beginA == endA && beginB == endB; |
| } |
| |
| /** @return start point in sequence A. */ |
| public final int getBeginA() { |
| return beginA; |
| } |
| |
| /** @return end point in sequence A. */ |
| public final int getEndA() { |
| return endA; |
| } |
| |
| /** @return start point in sequence B. */ |
| public final int getBeginB() { |
| return beginB; |
| } |
| |
| /** @return end point in sequence B. */ |
| public final int getEndB() { |
| return endB; |
| } |
| |
| /** @return length of the region in A. */ |
| public final int getLengthA() { |
| return endA - beginA; |
| } |
| |
| /** @return length of the region in B. */ |
| public final int getLengthB() { |
| return endB - beginB; |
| } |
| |
| /** |
| * Move the edit region by the specified amount. |
| * |
| * @param amount |
| * the region is shifted by this amount, and can be positive or |
| * negative. |
| * @since 4.8 |
| */ |
| public final void shift(int amount) { |
| beginA += amount; |
| endA += amount; |
| beginB += amount; |
| endB += amount; |
| } |
| |
| /** |
| * Construct a new edit representing the region before cut. |
| * |
| * @param cut |
| * the cut point. The beginning A and B points are used as the |
| * end points of the returned edit. |
| * @return an edit representing the slice of {@code this} edit that occurs |
| * before {@code cut} starts. |
| */ |
| public final Edit before(Edit cut) { |
| return new Edit(beginA, cut.beginA, beginB, cut.beginB); |
| } |
| |
| /** |
| * Construct a new edit representing the region after cut. |
| * |
| * @param cut |
| * the cut point. The ending A and B points are used as the |
| * starting points of the returned edit. |
| * @return an edit representing the slice of {@code this} edit that occurs |
| * after {@code cut} ends. |
| */ |
| public final Edit after(Edit cut) { |
| return new Edit(cut.endA, endA, cut.endB, endB); |
| } |
| |
| /** Increase {@link #getEndA()} by 1. */ |
| public void extendA() { |
| endA++; |
| } |
| |
| /** Increase {@link #getEndB()} by 1. */ |
| public void extendB() { |
| endB++; |
| } |
| |
| /** Swap A and B, so the edit goes the other direction. */ |
| public void swap() { |
| final int sBegin = beginA; |
| final int sEnd = endA; |
| |
| beginA = beginB; |
| endA = endB; |
| |
| beginB = sBegin; |
| endB = sEnd; |
| } |
| |
| @Override |
| public int hashCode() { |
| return beginA ^ endA; |
| } |
| |
| @Override |
| public boolean equals(final Object o) { |
| if (o instanceof Edit) { |
| final Edit e = (Edit) o; |
| return this.beginA == e.beginA && this.endA == e.endA |
| && this.beginB == e.beginB && this.endB == e.endB; |
| } |
| return false; |
| } |
| |
| @SuppressWarnings("nls") |
| @Override |
| public String toString() { |
| final Type t = getType(); |
| return t + "(" + beginA + "-" + endA + "," + beginB + "-" + endB + ")"; |
| } |
| } |
