org.eclipse.jgit.storage.dht/src/org/eclipse/jgit/storage/dht/RepresentationSelector.java

/*
 * Copyright (C) 2011, Google Inc.
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package org.eclipse.jgit.storage.dht;

import java.util.List;

import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.storage.pack.PackWriter;

final class RepresentationSelector extends BatchObjectLookup<DhtObjectToPack> {
	private final PackWriter packer;

	private final DhtObjectRepresentation rep;

	RepresentationSelector(PackWriter packer, DhtReader reader,
			ProgressMonitor monitor) {
		super(reader, monitor);
		setRetryMissingObjects(true);

		this.packer = packer;
		this.rep = new DhtObjectRepresentation();
	}

	protected void onResult(DhtObjectToPack obj, List<ObjectInfo> info) {
		// Go through the objects backwards. This is necessary because
		// info is sorted oldest->newest but PackWriter wants the reverse
		// order to try and prevent delta chain cycles.
		//
		for (int i = info.size() - 1; 0 <= i; i--) {
			rep.set(info.get(i));
			packer.select(obj, rep);
		}
	}
}