jgit/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsObjectRepresentation.java

/*
 * 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
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 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
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 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
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package org.eclipse.jgit.storage.dfs;

import static org.eclipse.jgit.storage.dfs.DfsObjDatabase.PackSource.GC;
import static org.eclipse.jgit.storage.dfs.DfsObjDatabase.PackSource.UNREACHABLE_GARBAGE;

import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.storage.dfs.DfsObjDatabase.PackSource;
import org.eclipse.jgit.storage.pack.ObjectToPack;
import org.eclipse.jgit.storage.pack.StoredObjectRepresentation;

class DfsObjectRepresentation extends StoredObjectRepresentation {
	final ObjectToPack object;

	DfsPackFile pack;

	/**
	 * Position of {@link #pack} in the reader's pack list. Lower numbers are
	 * newer/more recent packs and less likely to contain the best format for a
	 * base object. Higher numbered packs are bigger, more stable, and favored
	 * by PackWriter when selecting representations... but only if they come
	 * last in the representation ordering.
	 */
	int packIndex;

	long offset;

	int format;

	long length;

	ObjectId baseId;

	DfsObjectRepresentation(ObjectToPack object) {
		this.object = object;
	}

	@Override
	public int getFormat() {
		return format;
	}

	@Override
	public int getWeight() {
		return (int) Math.min(length, Integer.MAX_VALUE);
	}

	@Override
	public ObjectId getDeltaBase() {
		return baseId;
	}

	@Override
	public boolean wasDeltaAttempted() {
		if (pack != null) {
			PackSource source = pack.getPackDescription().getPackSource();
			return source == GC || source == UNREACHABLE_GARBAGE;
		}
		return false;
	}
}