Browse Source

PackBitmapIndex: Add AddToBitmapWithCacheFilter class

Add a new revwalk filter, AddToBitmapWithCachedFilter. This filter updates
a client-provided {@code BitmapBuilder} as a side effect of a revwalk.
Similar to {@code AddToBitmapFilter}, it short circuits the walk when it
encounters a commit which is included in the provided bitmap's BitmapIndex.
It also short circuits the walk if it encounters the client-provided
cached commit.

Change-Id: I62cb503016f4d3995d648d92b82baab7f93549a9
Signed-off-by: Yunjie Li <yunjieli@google.com>
master
Yunjie Li 5 years ago
parent
commit
067d946090
  1. 91
      org.eclipse.jgit/src/org/eclipse/jgit/internal/revwalk/AddToBitmapWithCacheFilter.java

91
org.eclipse.jgit/src/org/eclipse/jgit/internal/revwalk/AddToBitmapWithCacheFilter.java

@ -0,0 +1,91 @@
/*
* Copyright (c) 2020, Google LLC and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.internal.revwalk;
import org.eclipse.jgit.lib.BitmapIndex.Bitmap;
import org.eclipse.jgit.lib.BitmapIndex.BitmapBuilder;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.revwalk.filter.RevFilter;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevFlag;
/**
* A RevFilter that adds the visited commits to {@code bitmap} as a side effect.
* <p>
* When the walk hits a commit that is the same as {@code cachedCommit} or is
* part of {@code bitmap}'s BitmapIndex, that entire bitmap is ORed into
* {@code bitmap} and the commit and its parents are marked as SEEN so that the
* walk does not have to visit its ancestors. This ensures the walk is very
* short if there is good bitmap coverage.
*/
public class AddToBitmapWithCacheFilter extends RevFilter {
private final AnyObjectId cachedCommit;
private final Bitmap cachedBitmap;
private final BitmapBuilder bitmap;
/**
* Create a filter with a cached BitmapCommit that adds visited commits to
* the given bitmap.
*
* @param cachedCommit
* the cached commit
* @param cachedBitmap
* the bitmap corresponds to {@code cachedCommit}}
* @param bitmap
* bitmap to write visited commits to
*/
public AddToBitmapWithCacheFilter(AnyObjectId cachedCommit,
Bitmap cachedBitmap,
BitmapBuilder bitmap) {
this.cachedCommit = cachedCommit;
this.cachedBitmap = cachedBitmap;
this.bitmap = bitmap;
}
/** {@inheritDoc} */
@Override
public final boolean include(RevWalk rw, RevCommit c) {
Bitmap visitedBitmap;
if (bitmap.contains(c)) {
// already included
} else if ((visitedBitmap = bitmap.getBitmapIndex()
.getBitmap(c)) != null) {
bitmap.or(visitedBitmap);
} else if (cachedCommit.equals(c)) {
bitmap.or(cachedBitmap);
} else {
bitmap.addObject(c, Constants.OBJ_COMMIT);
return true;
}
for (RevCommit p : c.getParents()) {
p.add(RevFlag.SEEN);
}
return false;
}
/** {@inheritDoc} */
@Override
public final RevFilter clone() {
throw new UnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public final boolean requiresCommitBody() {
return false;
}
}
Loading…
Cancel
Save