http://www.eclipse.org/jgit//org.eclipse.jgit: Repository access and algorithms (Eclipse JGit Project)
  • Eclipse Distribution License (New BSD License)
  • Andrey Loskutov
  • Christian Halstrick
  • Dave Borowitz
  • David Pursehouse
  • Gunnar Wagenknecht
  • Jonathan Nieder
  • Jonathan Tan
  • Matthias Sohn
  • Sasa Zivkov
  • Terry Parker
  • Thomas Wolf 
/*
 * Copyright (C) 2010, Christian Halstrick <christian.halstrick@sap.com>
 * Copyright (C) 2010-2014, Stefan Lay <stefan.lay@sap.com>
 * Copyright (C) 2016, Laurent Delaigue <laurent.delaigue@obeo.fr>
 * 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.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import org.eclipse.jgit.annotations.Nullable;
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.GitAPIException;
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.events.WorkingTreeModifiedEvent;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.lib.Config.ConfigEnum;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.NullProgressMonitor;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectIdRef;
import org.eclipse.jgit.lib.ProgressMonitor;
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.MergeConfig;
import org.eclipse.jgit.merge.MergeMessageFormatter;
import org.eclipse.jgit.merge.MergeStrategy;
import org.eclipse.jgit.merge.Merger;
import org.eclipse.jgit.merge.ResolveMerger;
import org.eclipse.jgit.merge.ResolveMerger.MergeFailureReason;
import org.eclipse.jgit.merge.SquashMessageFormatter;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.revwalk.RevWalkUtils;
import org.eclipse.jgit.treewalk.FileTreeIterator;
import org.eclipse.jgit.util.StringUtils;


A class used to execute a Merge command. It has setters for all supported options and arguments of this command and a 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 call()) 
See Also:
/**
 * 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 <a href="http://www.kernel.org/pub/software/scm/git/docs/git-merge.html"
 *      >Git documentation about Merge</a>
 */
public class MergeCommand extends GitCommand<MergeResult> {

	private MergeStrategy mergeStrategy = MergeStrategy.RECURSIVE;

	private List<Ref> commits = new LinkedList<>();

	private Boolean squash;

	private FastForwardMode fastForwardMode;

	private String message;

	private boolean insertChangeId;

	private ProgressMonitor monitor = NullProgressMonitor.INSTANCE;

	
The modes available for fast forward merges corresponding to the
--ff, --no-ff and --ff-only
options under branch.<name>.mergeoptions.

/**
	 * The modes available for fast forward merges corresponding to the
	 * <code>--ff</code>, <code>--no-ff</code> and <code>--ff-only</code>
	 * options under <code>branch.&lt;name&gt;.mergeoptions</code>.
	 */
	public enum FastForwardMode implements ConfigEnum {
		
Corresponds to the default --ff option (for a fast forward update the
branch pointer only).

/**
		 * Corresponds to the default --ff option (for a fast forward update the
		 * branch pointer only).
		 */
		FF,
		
Corresponds to the --no-ff option (create a merge commit even for a
fast forward).

/**
		 * Corresponds to the --no-ff option (create a merge commit even for a
		 * fast forward).
		 */
		NO_FF,
		
Corresponds to the --ff-only option (abort unless the merge is a fast
forward).

/**
		 * Corresponds to the --ff-only option (abort unless the merge is a fast
		 * forward).
		 */
		FF_ONLY;

		@Override
		public String toConfigValue() {
			return "--" + name().toLowerCase(Locale.ROOT).replace('_', '-'); //$NON-NLS-1$
		}

		@Override
		public boolean matchConfigValue(String in) {
			if (StringUtils.isEmptyOrNull(in))
				return false;
			if (!in.startsWith("--")) //$NON-NLS-1$
				return false;
			return name().equalsIgnoreCase(in.substring(2).replace('-', '_'));
		}

		
The modes available for fast forward merges corresponding to the
options under merge.ff.

/**
		 * The modes available for fast forward merges corresponding to the
		 * options under <code>merge.ff</code>.
		 */
		public enum Merge {
			/**
			 * {@link FastForwardMode#FF}.
			 */
			TRUE,
			/**
			 * {@link FastForwardMode#NO_FF}.
			 */
			FALSE,
			/**
			 * {@link FastForwardMode#FF_ONLY}.
			 */
			ONLY;

			
Map from FastForwardMode to
FastForwardMode.Merge.

Params:
  • ffMode – 
           the FastForwardMode value to be mapped
Returns:the mapped FastForwardMode.Merge value
/**
			 * Map from <code>FastForwardMode</code> to
			 * <code>FastForwardMode.Merge</code>.
			 *
			 * @param ffMode
			 *            the <code>FastForwardMode</code> value to be mapped
			 * @return the mapped <code>FastForwardMode.Merge</code> value
			 */
			public static Merge valueOf(FastForwardMode ffMode) {
				switch (ffMode) {
				case NO_FF:
					return FALSE;
				case FF_ONLY:
					return ONLY;
				default:
					return TRUE;
				}
			}
		}

		
Map from FastForwardMode.Merge to
FastForwardMode.

Params:
  • ffMode – 
           the FastForwardMode.Merge value to be mapped
Returns:the mapped FastForwardMode value
/**
		 * Map from <code>FastForwardMode.Merge</code> to
		 * <code>FastForwardMode</code>.
		 *
		 * @param ffMode
		 *            the <code>FastForwardMode.Merge</code> value to be mapped
		 * @return the mapped <code>FastForwardMode</code> value
		 */
		public static FastForwardMode valueOf(FastForwardMode.Merge ffMode) {
			switch (ffMode) {
			case FALSE:
				return NO_FF;
			case ONLY:
				return FF_ONLY;
			default:
				return FF;
			}
		}
	}

	private Boolean commit;

	
Constructor for MergeCommand.

Params:
/**
	 * Constructor for MergeCommand.
	 *
	 * @param repo
	 *            the {@link org.eclipse.jgit.lib.Repository}
	 */
	protected MergeCommand(Repository repo) {
		super(repo);
	}

	
{@inheritDoc}

 Execute the Merge command with all the options and parameters collected by the setter methods (e.g. 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. 
/**
	 * {@inheritDoc}
	 * <p>
	 * Execute 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.
	 */
	@Override
	@SuppressWarnings("boxing")
	public MergeResult call() throws GitAPIException, NoHeadException,
			ConcurrentRefUpdateException, CheckoutConflictException,
			InvalidMergeHeadsException, WrongRepositoryStateException, NoMessageException {
		checkCallable();
		fallBackToConfiguration();
		checkParameters();

		DirCacheCheckout dco = null;
		try (RevWalk revWalk = new RevWalk(repo)) {
			Ref head = repo.exactRef(Constants.HEAD);
			if (head == null)
				throw new NoHeadException(
						JGitText.get().commitOnRepoWithoutHEADCurrentlyNotSupported);
			StringBuilder refLogMessage = new StringBuilder("merge "); //$NON-NLS-1$

			// Check for FAST_FORWARD, ALREADY_UP_TO_DATE

			// we know for now there is only one commit
			Ref ref = commits.get(0);

			refLogMessage.append(ref.getName());

			// handle annotated tags
			ref = repo.getRefDatabase().peel(ref);
			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);
				dco = new DirCacheCheckout(repo,
						repo.lockDirCache(), srcCommit.getTree());
				dco.setFailOnConflict(true);
				dco.setProgressMonitor(monitor);
				dco.checkout();
				RefUpdate refUpdate = repo
						.updateRef(head.getTarget().getName());
				refUpdate.setNewObjectId(objectId);
				refUpdate.setExpectedOldObjectId(null);
				refUpdate.setRefLogMessage("initial pull", false); //$NON-NLS-1$
				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)
					&& fastForwardMode != FastForwardMode.NO_FF) {
				// FAST_FORWARD detected: skip doing a real merge but only
				// update HEAD
				refLogMessage.append(": " + MergeStatus.FAST_FORWARD); //$NON-NLS-1$
				dco = new DirCacheCheckout(repo,
						headCommit.getTree(), repo.lockDirCache(),
						srcCommit.getTree());
				dco.setProgressMonitor(monitor);
				dco.setFailOnConflict(true);
				dco.checkout();
				String msg = null;
				ObjectId newHead, base = null;
				MergeStatus mergeStatus = null;
				if (!squash) {
					updateHead(refLogMessage, srcCommit, headId);
					newHead = base = srcCommit;
					mergeStatus = MergeStatus.FAST_FORWARD;
				} else {
					msg = JGitText.get().squashCommitNotUpdatingHEAD;
					newHead = base = headId;
					mergeStatus = MergeStatus.FAST_FORWARD_SQUASHED;
					List<RevCommit> squashedCommits = RevWalkUtils.find(
							revWalk, srcCommit, headCommit);
					String squashMessage = new SquashMessageFormatter().format(
							squashedCommits, head);
					repo.writeSquashCommitMsg(squashMessage);
				}
				setCallable(false);
				return new MergeResult(newHead, base, new ObjectId[] {
						headCommit, srcCommit }, mergeStatus, mergeStrategy,
						null, msg);
			} else {
				if (fastForwardMode == FastForwardMode.FF_ONLY) {
					return new MergeResult(headCommit, srcCommit,
							new ObjectId[] { headCommit, srcCommit },
							MergeStatus.ABORTED, mergeStrategy, null, null);
				}
				String mergeMessage = ""; //$NON-NLS-1$
				if (!squash) {
					if (message != null)
						mergeMessage = message;
					else
						mergeMessage = new MergeMessageFormatter().format(
							commits, head);
					repo.writeMergeCommitMsg(mergeMessage);
					repo.writeMergeHeads(Arrays.asList(ref.getObjectId()));
				} else {
					List<RevCommit> squashedCommits = RevWalkUtils.find(
							revWalk, srcCommit, headCommit);
					String squashMessage = new SquashMessageFormatter().format(
							squashedCommits, head);
					repo.writeSquashCommitMsg(squashMessage);
				}
				Merger merger = mergeStrategy.newMerger(repo);
				merger.setProgressMonitor(monitor);
				boolean noProblems;
				Map<String, org.eclipse.jgit.merge.MergeResult<?>> lowLevelResults = null;
				Map<String, MergeFailureReason> failingPaths = null;
				List<String> unmergedPaths = null;
				if (merger instanceof ResolveMerger) {
					ResolveMerger resolveMerger = (ResolveMerger) merger;
					resolveMerger.setCommitNames(new String[] {
							"BASE", "HEAD", ref.getName() }); //$NON-NLS-1$ //$NON-NLS-2$
					resolveMerger.setWorkingTreeIterator(new FileTreeIterator(repo));
					noProblems = merger.merge(headCommit, srcCommit);
					lowLevelResults = resolveMerger
							.getMergeResults();
					failingPaths = resolveMerger.getFailingPaths();
					unmergedPaths = resolveMerger.getUnmergedPaths();
					if (!resolveMerger.getModifiedFiles().isEmpty()) {
						repo.fireEvent(new WorkingTreeModifiedEvent(
								resolveMerger.getModifiedFiles(), null));
					}
				} else
					noProblems = merger.merge(headCommit, srcCommit);
				refLogMessage.append(": Merge made by "); //$NON-NLS-1$
				if (!revWalk.isMergedInto(headCommit, srcCommit))
					refLogMessage.append(mergeStrategy.getName());
				else
					refLogMessage.append("recursive"); //$NON-NLS-1$
				refLogMessage.append('.');
				if (noProblems) {
					dco = new DirCacheCheckout(repo,
							headCommit.getTree(), repo.lockDirCache(),
							merger.getResultTreeId());
					dco.setFailOnConflict(true);
					dco.setProgressMonitor(monitor);
					dco.checkout();

					String msg = null;
					ObjectId newHeadId = null;
					MergeStatus mergeStatus = null;
					if (!commit && squash) {
						mergeStatus = MergeStatus.MERGED_SQUASHED_NOT_COMMITTED;
					}
					if (!commit && !squash) {
						mergeStatus = MergeStatus.MERGED_NOT_COMMITTED;
					}
					if (commit && !squash) {
						try (Git git = new Git(getRepository())) {
							newHeadId = git.commit()
									.setReflogComment(refLogMessage.toString())
									.setInsertChangeId(insertChangeId)
									.call().getId();
						}
						mergeStatus = MergeStatus.MERGED;
						getRepository().autoGC(monitor);
					}
					if (commit && squash) {
						msg = JGitText.get().squashCommitNotUpdatingHEAD;
						newHeadId = headCommit.getId();
						mergeStatus = MergeStatus.MERGED_SQUASHED;
					}
					return new MergeResult(newHeadId, null,
							new ObjectId[] { headCommit.getId(),
									srcCommit.getId() }, mergeStatus,
							mergeStrategy, null, msg);
				} else {
					if (failingPaths != null) {
						repo.writeMergeCommitMsg(null);
						repo.writeMergeHeads(null);
						return new MergeResult(null, merger.getBaseCommitId(),
								new ObjectId[] {
										headCommit.getId(), srcCommit.getId() },
								MergeStatus.FAILED, mergeStrategy,
								lowLevelResults, failingPaths, null);
					} else {
						String mergeMessageWithConflicts = new MergeMessageFormatter()
								.formatWithConflicts(mergeMessage,
										unmergedPaths);
						repo.writeMergeCommitMsg(mergeMessageWithConflicts);
						return new MergeResult(null, merger.getBaseCommitId(),
								new ObjectId[] { headCommit.getId(),
										srcCommit.getId() },
								MergeStatus.CONFLICTING, mergeStrategy,
								lowLevelResults, null);
					}
				}
			}
		} catch (org.eclipse.jgit.errors.CheckoutConflictException e) {
			List<String> conflicts = (dco == null) ? Collections
					.<String> emptyList() : dco.getConflicts();
			throw new CheckoutConflictException(conflicts, e);
		} catch (IOException e) {
			throw new JGitInternalException(
					MessageFormat.format(
							JGitText.get().exceptionCaughtDuringExecutionOfMergeCommand,
							e), e);
		}
	}

	private void checkParameters() throws InvalidMergeHeadsException {
		if (squash.booleanValue() && fastForwardMode == FastForwardMode.NO_FF) {
			throw new JGitInternalException(
					JGitText.get().cannotCombineSquashWithNoff);
		}

		if (commits.size() != 1)
			throw new InvalidMergeHeadsException(
					commits.isEmpty() ? JGitText.get().noMergeHeadSpecified
							: MessageFormat.format(
									JGitText.get().mergeStrategyDoesNotSupportHeads,
									mergeStrategy.getName(),
									Integer.valueOf(commits.size())));
	}

	
Use values from the configuration if they have not been explicitly
defined via the setters

/**
	 * Use values from the configuration if they have not been explicitly
	 * defined via the setters
	 */
	private void fallBackToConfiguration() {
		MergeConfig config = MergeConfig.getConfigForCurrentBranch(repo);
		if (squash == null)
			squash = Boolean.valueOf(config.isSquash());
		if (commit == null)
			commit = Boolean.valueOf(config.isCommit());
		if (fastForwardMode == null)
			fastForwardMode = config.getFastForwardMode();
	}

	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));
		}
	}

	
Set merge strategy

Params:
Returns:this
/**
	 * Set merge strategy
	 *
	 * @param mergeStrategy
	 *            the {@link org.eclipse.jgit.merge.MergeStrategy} to be used
	 * @return {@code this}
	 */
	public MergeCommand setStrategy(MergeStrategy mergeStrategy) {
		checkCallable();
		this.mergeStrategy = mergeStrategy;
		return this;
	}

	
Reference to a commit to be merged with the current head

Params:
  • aCommit – 
           a reference to a commit which is merged with the current head
Returns:this
/**
	 * Reference to a commit to be merged with the current head
	 *
	 * @param aCommit
	 *            a reference to a commit which is merged with the current head
	 * @return {@code this}
	 */
	public MergeCommand include(Ref aCommit) {
		checkCallable();
		commits.add(aCommit);
		return this;
	}

	
Id of a commit which is to be merged with the current head

Params:
  • aCommit – 
           the Id of a commit which is merged with the current head
Returns:this
/**
	 * Id of a commit which is to be merged with the current head
	 *
	 * @param aCommit
	 *            the Id of a commit which is merged with the current head
	 * @return {@code this}
	 */
	public MergeCommand include(AnyObjectId aCommit) {
		return include(aCommit.getName(), aCommit);
	}

	
Include a commit

Params:
  • name –  a name of a Ref pointing to the commit
  • aCommit – 
           the Id of a commit which is merged with the current head
Returns:this
/**
	 * Include a commit
	 *
	 * @param name
	 *            a name of a {@code Ref} pointing to the commit
	 * @param aCommit
	 *            the Id of a commit which is merged with the current head
	 * @return {@code this}
	 */
	public MergeCommand include(String name, AnyObjectId aCommit) {
		return include(new ObjectIdRef.Unpeeled(Storage.LOOSE, name,
				aCommit.copy()));
	}

	
If true, will prepare the next commit in working tree and
index as if a real merge happened, but do not make the commit or move the
HEAD. Otherwise, perform the merge and commit the result.


In case the merge was successful but this flag was set to
true a MergeResult with status MergeStatus.MERGED_SQUASHED or MergeStatus.FAST_FORWARD_SQUASHED is returned. 
Params:
  • squash – 
           whether to squash commits or not
Returns:this
Since:2.0
/**
	 * If <code>true</code>, will prepare the next commit in working tree and
	 * index as if a real merge happened, but do not make the commit or move the
	 * HEAD. Otherwise, perform the merge and commit the result.
	 * <p>
	 * In case the merge was successful but this flag was set to
	 * <code>true</code> a {@link org.eclipse.jgit.api.MergeResult} with status
	 * {@link org.eclipse.jgit.api.MergeResult.MergeStatus#MERGED_SQUASHED} or
	 * {@link org.eclipse.jgit.api.MergeResult.MergeStatus#FAST_FORWARD_SQUASHED}
	 * is returned.
	 *
	 * @param squash
	 *            whether to squash commits or not
	 * @return {@code this}
	 * @since 2.0
	 */
	public MergeCommand setSquash(boolean squash) {
		checkCallable();
		this.squash = Boolean.valueOf(squash);
		return this;
	}

	
Sets the fast forward mode.

Params:
  • fastForwardMode –  corresponds to the --ff/--no-ff/--ff-only options. If null use the value of the merge.ff option configured in git config. If this option is not configured --ff is the built-in default.
Returns:this
Since:2.2
/**
	 * Sets the fast forward mode.
	 *
	 * @param fastForwardMode
	 *            corresponds to the --ff/--no-ff/--ff-only options. If
	 *            {@code null} use the value of the {@code merge.ff} option
	 *            configured in git config. If this option is not configured
	 *            --ff is the built-in default.
	 * @return {@code this}
	 * @since 2.2
	 */
	public MergeCommand setFastForward(
			@Nullable FastForwardMode fastForwardMode) {
		checkCallable();
		this.fastForwardMode = fastForwardMode;
		return this;
	}

	
Controls whether the merge command should automatically commit after a
successful merge

Params:
  • commit – 
           true if this command should commit (this is the
           default behavior). false if this command should
           not commit. In case the merge was successful but this flag was
           set to false a MergeResult with type MergeResult with status MergeStatus.MERGED_NOT_COMMITTED is returned
Returns:this
Since:3.0
/**
	 * Controls whether the merge command should automatically commit after a
	 * successful merge
	 *
	 * @param commit
	 *            <code>true</code> if this command should commit (this is the
	 *            default behavior). <code>false</code> if this command should
	 *            not commit. In case the merge was successful but this flag was
	 *            set to <code>false</code> a
	 *            {@link org.eclipse.jgit.api.MergeResult} with type
	 *            {@link org.eclipse.jgit.api.MergeResult} with status
	 *            {@link org.eclipse.jgit.api.MergeResult.MergeStatus#MERGED_NOT_COMMITTED}
	 *            is returned
	 * @return {@code this}
	 * @since 3.0
	 */
	public MergeCommand setCommit(boolean commit) {
		this.commit = Boolean.valueOf(commit);
		return this;
	}

	
Set the commit message to be used for the merge commit (in case one is
created)

Params:
  • message – 
           the message to be used for the merge commit
Returns:this
Since:3.5
/**
	 * Set the commit message to be used for the merge commit (in case one is
	 * created)
	 *
	 * @param message
	 *            the message to be used for the merge commit
	 * @return {@code this}
	 * @since 3.5
	 */
	public MergeCommand setMessage(String message) {
		this.message = message;
		return this;
	}

	
If set to true a change id will be inserted into the commit message
An existing change id is not replaced. An initial change id (I000...)
will be replaced by the change id.

Params:
  • insertChangeId – 
           whether to insert a change id
Returns:this
Since:5.0
/**
	 * If set to true a change id will be inserted into the commit message
	 *
	 * An existing change id is not replaced. An initial change id (I000...)
	 * will be replaced by the change id.
	 *
	 * @param insertChangeId
	 *            whether to insert a change id
	 * @return {@code this}
	 * @since 5.0
	 */
	public MergeCommand setInsertChangeId(boolean insertChangeId) {
		checkCallable();
		this.insertChangeId = insertChangeId;
		return this;
	}

	
The progress monitor associated with the diff operation. By default, this
is set to NullProgressMonitor

Params:
  • monitor – 
           A progress monitor
See Also:
  • NullProgressMonitor
Returns:this instance
Since:4.2
/**
	 * The progress monitor associated with the diff operation. By default, this
	 * is set to <code>NullProgressMonitor</code>
	 *
	 * @see NullProgressMonitor
	 * @param monitor
	 *            A progress monitor
	 * @return this instance
	 * @since 4.2
	 */
	public MergeCommand setProgressMonitor(ProgressMonitor monitor) {
		if (monitor == null) {
			monitor = NullProgressMonitor.INSTANCE;
		}
		this.monitor = monitor;
		return this;
	}
}