| /* |
| * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> |
| * 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.revwalk; |
| |
| import java.io.IOException; |
| |
| import org.eclipse.jgit.errors.IncorrectObjectTypeException; |
| import org.eclipse.jgit.errors.MissingObjectException; |
| |
| /** |
| * Produces commits for RevWalk to return to applications. |
| * <p> |
| * Implementations of this basic class provide the real work behind RevWalk. |
| * Conceptually a Generator is an iterator or a queue, it returns commits until |
| * there are no more relevant. Generators may be piped/stacked together to |
| * create a more complex set of operations. |
| * |
| * @see PendingGenerator |
| * @see StartGenerator |
| */ |
| abstract class Generator { |
| /** Commits are sorted by commit date and time, descending. */ |
| static final int SORT_COMMIT_TIME_DESC = 1 << 0; |
| |
| /** Output may have {@link RevWalk#REWRITE} marked on it. */ |
| static final int HAS_REWRITE = 1 << 1; |
| |
| /** Output needs {@link RewriteGenerator}. */ |
| static final int NEEDS_REWRITE = 1 << 2; |
| |
| /** Topological ordering is enforced (all children before parents). */ |
| static final int SORT_TOPO = 1 << 3; |
| |
| /** Output may have {@link RevWalk#UNINTERESTING} marked on it. */ |
| static final int HAS_UNINTERESTING = 1 << 4; |
| |
| protected final boolean firstParent; |
| |
| protected Generator(boolean firstParent) { |
| this.firstParent = firstParent; |
| } |
| |
| /** |
| * Connect the supplied queue to this generator's own free list (if any). |
| * |
| * @param q |
| * another FIFO queue that wants to share our queue's free list. |
| */ |
| void shareFreeList(BlockRevQueue q) { |
| // Do nothing by default. |
| } |
| |
| /** |
| * Obtain flags describing the output behavior of this generator. |
| * |
| * @return one or more of the constants declared in this class, describing |
| * how this generator produces its results. |
| */ |
| abstract int outputType(); |
| |
| /** |
| * Return the next commit to the application, or the next generator. |
| * |
| * @return next available commit; null if no more are to be returned. |
| * @throws MissingObjectException |
| * @throws IncorrectObjectTypeException |
| * @throws IOException |
| */ |
| abstract RevCommit next() throws MissingObjectException, |
| IncorrectObjectTypeException, IOException; |
| } |