123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172 |
- /*
- * Copyright (C) 2008-2009, Google Inc.
- * Copyright (C) 2009, Matthias Sohn <matthias.sohn@sap.com>
- * Copyright (C) 2012, Research In Motion Limited
- * 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.merge;
-
- import java.text.MessageFormat;
- import java.util.HashMap;
-
- import org.eclipse.jgit.internal.JGitText;
- import org.eclipse.jgit.lib.Repository;
-
- /**
- * A method of combining two or more trees together to form an output tree.
- * <p>
- * Different strategies may employ different techniques for deciding which paths
- * (and ObjectIds) to carry from the input trees into the final output tree.
- */
- public abstract class MergeStrategy {
- /** Simple strategy that sets the output tree to the first input tree. */
- public static final MergeStrategy OURS = new StrategyOneSided("ours", 0); //$NON-NLS-1$
-
- /** Simple strategy that sets the output tree to the second input tree. */
- public static final MergeStrategy THEIRS = new StrategyOneSided("theirs", 1); //$NON-NLS-1$
-
- /** Simple strategy to merge paths, without simultaneous edits. */
- public static final ThreeWayMergeStrategy SIMPLE_TWO_WAY_IN_CORE = new StrategySimpleTwoWayInCore();
-
- /**
- * Simple strategy to merge paths. It tries to merge also contents. Multiple
- * merge bases are not supported
- */
- public static final ThreeWayMergeStrategy RESOLVE = new StrategyResolve();
-
- /**
- * Recursive strategy to merge paths. It tries to merge also contents.
- * Multiple merge bases are supported
- */
- public static final ThreeWayMergeStrategy RECURSIVE = new StrategyRecursive();
-
- private static final HashMap<String, MergeStrategy> STRATEGIES = new HashMap<String, MergeStrategy>();
-
- static {
- register(OURS);
- register(THEIRS);
- register(SIMPLE_TWO_WAY_IN_CORE);
- register(RESOLVE);
- register(RECURSIVE);
- }
-
- /**
- * Register a merge strategy so it can later be obtained by name.
- *
- * @param imp
- * the strategy to register.
- * @throws IllegalArgumentException
- * a strategy by the same name has already been registered.
- */
- public static void register(final MergeStrategy imp) {
- register(imp.getName(), imp);
- }
-
- /**
- * Register a merge strategy so it can later be obtained by name.
- *
- * @param name
- * name the strategy can be looked up under.
- * @param imp
- * the strategy to register.
- * @throws IllegalArgumentException
- * a strategy by the same name has already been registered.
- */
- public static synchronized void register(final String name,
- final MergeStrategy imp) {
- if (STRATEGIES.containsKey(name))
- throw new IllegalArgumentException(MessageFormat.format(
- JGitText.get().mergeStrategyAlreadyExistsAsDefault, name));
- STRATEGIES.put(name, imp);
- }
-
- /**
- * Locate a strategy by name.
- *
- * @param name
- * name of the strategy to locate.
- * @return the strategy instance; null if no strategy matches the name.
- */
- public static synchronized MergeStrategy get(final String name) {
- return STRATEGIES.get(name);
- }
-
- /**
- * Get all registered strategies.
- *
- * @return the registered strategy instances. No inherit order is returned;
- * the caller may modify (and/or sort) the returned array if
- * necessary to obtain a reasonable ordering.
- */
- public static synchronized MergeStrategy[] get() {
- final MergeStrategy[] r = new MergeStrategy[STRATEGIES.size()];
- STRATEGIES.values().toArray(r);
- return r;
- }
-
- /** @return default name of this strategy implementation. */
- public abstract String getName();
-
- /**
- * Create a new merge instance.
- *
- * @param db
- * repository database the merger will read from, and eventually
- * write results back to.
- * @return the new merge instance which implements this strategy.
- */
- public abstract Merger newMerger(Repository db);
-
- /**
- * Create a new merge instance.
- *
- * @param db
- * repository database the merger will read from, and eventually
- * write results back to.
- * @param inCore
- * the merge will happen in memory, working folder will not be
- * modified, in case of a non-trivial merge that requires manual
- * resolution, the merger will fail.
- * @return the new merge instance which implements this strategy.
- */
- public abstract Merger newMerger(Repository db, boolean inCore);
- }
|