org.eclipse.jgit.blame.Region Maven / Gradle / Ivy
/*
* Copyright (C) 2011, 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
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* 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
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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package org.eclipse.jgit.blame;
/**
* Region of the result that still needs to be computed.
*
* Regions are held in a singly-linked-list by {@link Candidate} using the
* {@link Candidate#regionList} field. The list is kept in sorted order by
* {@link #resultStart}.
*/
class Region {
/** Next entry in the region linked list. */
Region next;
/** First position of this region in the result file blame is computing. */
int resultStart;
/** First position in the {@link Candidate} that owns this Region. */
int sourceStart;
/** Length of the region, always >= 1. */
int length;
Region(int rs, int ss, int len) {
resultStart = rs;
sourceStart = ss;
length = len;
}
/**
* Copy the entire result region, but at a new source position.
*
* @param newSource
* the new source position.
* @return the same result region, but offset for a new source.
*/
Region copy(int newSource) {
return new Region(resultStart, newSource, length);
}
/**
* Split the region, assigning a new source position to the first half.
*
* @param newSource
* the new source position.
* @param newLen
* length of the new region.
* @return the first half of the region, at the new source.
*/
Region splitFirst(int newSource, int newLen) {
return new Region(resultStart, newSource, newLen);
}
/**
* Edit this region to remove the first {@code d} elements.
*
* @param d
* number of elements to remove from the start of this region.
*/
void slideAndShrink(int d) {
resultStart += d;
sourceStart += d;
length -= d;
}
Region deepCopy() {
Region head = new Region(resultStart, sourceStart, length);
Region tail = head;
for (Region n = next; n != null; n = n.next) {
Region q = new Region(n.resultStart, n.sourceStart, n.length);
tail.next = q;
tail = q;
}
return head;
}
@Override
public String toString() {
StringBuilder buf = new StringBuilder();
Region r = this;
do {
if (r != this)
buf.append(',');
buf.append(r.resultStart);
buf.append('-');
buf.append(r.resultStart + r.length);
r = r.next;
} while (r != null);
return buf.toString();
}
}