/* * Copyright (C) 2010, Christian Halstrick * Copyright (C) 2010, Stefan Lay * 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.api; import java.io.IOException; import java.text.MessageFormat; import java.util.Arrays; import java.util.LinkedList; import java.util.List; import java.util.Map; import org.eclipse.jgit.JGitText; import org.eclipse.jgit.api.MergeResult.MergeStatus; import org.eclipse.jgit.api.errors.CheckoutConflictException; import org.eclipse.jgit.api.errors.ConcurrentRefUpdateException; import org.eclipse.jgit.api.errors.InvalidMergeHeadsException; import org.eclipse.jgit.api.errors.JGitInternalException; import org.eclipse.jgit.api.errors.NoHeadException; import org.eclipse.jgit.api.errors.NoMessageException; import org.eclipse.jgit.api.errors.WrongRepositoryStateException; import org.eclipse.jgit.dircache.DirCacheCheckout; import org.eclipse.jgit.lib.AnyObjectId; import org.eclipse.jgit.lib.Constants; import org.eclipse.jgit.lib.ObjectId; import org.eclipse.jgit.lib.ObjectIdRef; import org.eclipse.jgit.lib.Ref; import org.eclipse.jgit.lib.Ref.Storage; import org.eclipse.jgit.lib.RefUpdate; import org.eclipse.jgit.lib.RefUpdate.Result; import org.eclipse.jgit.lib.Repository; import org.eclipse.jgit.merge.MergeMessageFormatter; import org.eclipse.jgit.merge.MergeStrategy; import org.eclipse.jgit.merge.ResolveMerger; import org.eclipse.jgit.merge.ResolveMerger.MergeFailureReason; import org.eclipse.jgit.merge.ThreeWayMerger; import org.eclipse.jgit.revwalk.RevCommit; import org.eclipse.jgit.revwalk.RevWalk; import org.eclipse.jgit.treewalk.FileTreeIterator; /** * A class used to execute a {@code Merge} command. It has setters for all * supported options and arguments of this command and a {@link #call()} method * to finally execute the command. Each instance of this class should only be * used for one invocation of the command (means: one call to {@link #call()}) * * @see Git documentation about Merge */ public class MergeCommand extends GitCommand { private MergeStrategy mergeStrategy = MergeStrategy.RESOLVE; private List commits = new LinkedList(); /** * @param repo */ protected MergeCommand(Repository repo) { super(repo); } /** * Executes the {@code Merge} command with all the options and parameters * collected by the setter methods (e.g. {@link #include(Ref)}) of this * class. Each instance of this class should only be used for one invocation * of the command. Don't call this method twice on an instance. * * @return the result of the merge */ public MergeResult call() throws NoHeadException, ConcurrentRefUpdateException, CheckoutConflictException, InvalidMergeHeadsException, WrongRepositoryStateException, NoMessageException { checkCallable(); if (commits.size() != 1) throw new InvalidMergeHeadsException( commits.isEmpty() ? JGitText.get().noMergeHeadSpecified : MessageFormat.format( JGitText.get().mergeStrategyDoesNotSupportHeads, mergeStrategy.getName(), Integer.valueOf(commits.size()))); RevWalk revWalk = null; try { Ref head = repo.getRef(Constants.HEAD); if (head == null) throw new NoHeadException( JGitText.get().commitOnRepoWithoutHEADCurrentlyNotSupported); StringBuilder refLogMessage = new StringBuilder("merge "); // Check for FAST_FORWARD, ALREADY_UP_TO_DATE revWalk = new RevWalk(repo); // we know for now there is only one commit Ref ref = commits.get(0); refLogMessage.append(ref.getName()); // handle annotated tags ObjectId objectId = ref.getPeeledObjectId(); if (objectId == null) objectId = ref.getObjectId(); RevCommit srcCommit = revWalk.lookupCommit(objectId); ObjectId headId = head.getObjectId(); if (headId == null) { revWalk.parseHeaders(srcCommit); DirCacheCheckout dco = new DirCacheCheckout(repo, repo.lockDirCache(), srcCommit.getTree()); dco.setFailOnConflict(true); dco.checkout(); RefUpdate refUpdate = repo .updateRef(head.getTarget().getName()); refUpdate.setNewObjectId(objectId); refUpdate.setExpectedOldObjectId(null); refUpdate.setRefLogMessage("initial pull", false); if (refUpdate.update() != Result.NEW) throw new NoHeadException( JGitText.get().commitOnRepoWithoutHEADCurrentlyNotSupported); setCallable(false); return new MergeResult(srcCommit, srcCommit, new ObjectId[] { null, srcCommit }, MergeStatus.FAST_FORWARD, mergeStrategy, null, null); } RevCommit headCommit = revWalk.lookupCommit(headId); if (revWalk.isMergedInto(srcCommit, headCommit)) { setCallable(false); return new MergeResult(headCommit, srcCommit, new ObjectId[] { headCommit, srcCommit }, MergeStatus.ALREADY_UP_TO_DATE, mergeStrategy, null, null); } else if (revWalk.isMergedInto(headCommit, srcCommit)) { // FAST_FORWARD detected: skip doing a real merge but only // update HEAD refLogMessage.append(": " + MergeStatus.FAST_FORWARD); DirCacheCheckout dco = new DirCacheCheckout(repo, headCommit.getTree(), repo.lockDirCache(), srcCommit.getTree()); dco.setFailOnConflict(true); dco.checkout(); updateHead(refLogMessage, srcCommit, headId); setCallable(false); return new MergeResult(srcCommit, srcCommit, new ObjectId[] { headCommit, srcCommit }, MergeStatus.FAST_FORWARD, mergeStrategy, null, null); } else { repo.writeMergeCommitMsg(new MergeMessageFormatter().format( commits, head)); repo.writeMergeHeads(Arrays.asList(ref.getObjectId())); ThreeWayMerger merger = (ThreeWayMerger) mergeStrategy .newMerger(repo); boolean noProblems; Map> lowLevelResults = null; Map failingPaths = null; if (merger instanceof ResolveMerger) { ResolveMerger resolveMerger = (ResolveMerger) merger; resolveMerger.setCommitNames(new String[] { "BASE", "HEAD", ref.getName() }); resolveMerger.setWorkingTreeIterator(new FileTreeIterator(repo)); noProblems = merger.merge(headCommit, srcCommit); lowLevelResults = resolveMerger .getMergeResults(); failingPaths = resolveMerger.getFailingPaths(); } else noProblems = merger.merge(headCommit, srcCommit); if (noProblems) { DirCacheCheckout dco = new DirCacheCheckout(repo, headCommit.getTree(), repo.lockDirCache(), merger.getResultTreeId()); dco.setFailOnConflict(true); dco.checkout(); RevCommit newHead = new Git(getRepository()).commit().call(); return new MergeResult(newHead.getId(), null, new ObjectId[] { headCommit.getId(), srcCommit.getId() }, MergeStatus.MERGED, mergeStrategy, null, null); } else { if (failingPaths != null) { repo.writeMergeCommitMsg(null); repo.writeMergeHeads(null); return new MergeResult(null, merger.getBaseCommit(0, 1), new ObjectId[] { headCommit.getId(), srcCommit.getId() }, MergeStatus.FAILED, mergeStrategy, lowLevelResults, null); } else return new MergeResult(null, merger.getBaseCommit(0, 1), new ObjectId[] { headCommit.getId(), srcCommit.getId() }, MergeStatus.CONFLICTING, mergeStrategy, lowLevelResults, null); } } } catch (IOException e) { throw new JGitInternalException( MessageFormat.format( JGitText.get().exceptionCaughtDuringExecutionOfMergeCommand, e), e); } finally { if (revWalk != null) revWalk.release(); } } private void updateHead(StringBuilder refLogMessage, ObjectId newHeadId, ObjectId oldHeadID) throws IOException, ConcurrentRefUpdateException { RefUpdate refUpdate = repo.updateRef(Constants.HEAD); refUpdate.setNewObjectId(newHeadId); refUpdate.setRefLogMessage(refLogMessage.toString(), false); refUpdate.setExpectedOldObjectId(oldHeadID); Result rc = refUpdate.update(); switch (rc) { case NEW: case FAST_FORWARD: return; case REJECTED: case LOCK_FAILURE: throw new ConcurrentRefUpdateException( JGitText.get().couldNotLockHEAD, refUpdate.getRef(), rc); default: throw new JGitInternalException(MessageFormat.format( JGitText.get().updatingRefFailed, Constants.HEAD, newHeadId.toString(), rc)); } } /** * * @param mergeStrategy * the {@link MergeStrategy} to be used * @return {@code this} */ public MergeCommand setStrategy(MergeStrategy mergeStrategy) { checkCallable(); this.mergeStrategy = mergeStrategy; return this; } /** * @param commit * a reference to a commit which is merged with the current head * @return {@code this} */ public MergeCommand include(Ref commit) { checkCallable(); commits.add(commit); return this; } /** * @param commit * the Id of a commit which is merged with the current head * @return {@code this} */ public MergeCommand include(AnyObjectId commit) { return include(commit.getName(), commit); } /** * @param name * a name given to the commit * @param commit * the Id of a commit which is merged with the current head * @return {@code this} */ public MergeCommand include(String name, AnyObjectId commit) { return include(new ObjectIdRef.Unpeeled(Storage.LOOSE, name, commit.copy())); } }