/*
* Copyright (c) 2011 Kevin Sawicki <kevinsawicki@gmail.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
package org.gitective.core;
import static org.eclipse.jgit.lib.Constants.HEAD;
import static org.eclipse.jgit.lib.Constants.MASTER;
import static org.eclipse.jgit.lib.Constants.R_HEADS;
import static org.eclipse.jgit.lib.Constants.R_REMOTES;
import static org.eclipse.jgit.lib.Constants.R_TAGS;
import static org.eclipse.jgit.revwalk.filter.RevFilter.MERGE_BASE;
import java.io.IOException;
import java.text.MessageFormat;
import java.util.Collection;
import java.util.HashSet;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.RefDatabase;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
/**
* Utilities for dealing with Git commits.
* <p>
* This class provides helpers for finding the commits that branches and tags
* reference.
*/
public abstract class CommitUtils {
/**
* Get the commit that the revision references.
*
* @param repository
* @param revision
* @return commit
*/
public static RevCommit getCommit(final Repository repository,
final String revision) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (revision == null)
throw new IllegalArgumentException(Assert.formatNotNull("Revision"));
if (revision.length() == 0)
throw new IllegalArgumentException(
Assert.formatNotEmpty("Revision"));
return parse(repository, resolve(repository, revision));
}
/**
* Get the commit with the given id
*
* @param repository
* @param commitId
* @return commit
*/
public static RevCommit getCommit(final Repository repository,
final ObjectId commitId) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (commitId == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Commit id"));
return parse(repository, commitId);
}
/**
* Get the HEAD commit in the given repository.
*
* @param repository
* @return commit never null
*/
public static RevCommit getHead(final Repository repository) {
return getCommit(repository, HEAD);
}
/**
* Get the commit at the tip of the master branch in the given repository.
*
* @param repository
* @return commit never null
*/
public static RevCommit getMaster(final Repository repository) {
return getCommit(repository, MASTER);
}
/**
* Get the common base commit of the given commits.
*
* @param repository
* @param commits
* @return base commit or null if none
*/
public static RevCommit getBase(final Repository repository,
final ObjectId... commits) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (commits == null)
throw new IllegalArgumentException(Assert.formatNotNull("Commits"));
if (commits.length == 0)
throw new IllegalArgumentException(Assert.formatNotEmpty("Commits"));
return walkToBase(repository, commits);
}
/**
* Get the common base commit between the given revisions.
*
* @param repository
* @param revisions
* @return base commit or null if none
*/
public static RevCommit getBase(final Repository repository,
final String... revisions) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (revisions == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Revisions"));
if (revisions.length == 0)
throw new IllegalArgumentException(
Assert.formatNotEmpty("Revisions"));
final int length = revisions.length;
final ObjectId[] commits = new ObjectId[length];
for (int i = 0; i < length; i++) {
commits[i] = strictResolve(repository, revisions[i]);
}
return walkToBase(repository, commits);
}
/**
* Get the commit that the given name references.
*
* @param repository
* @param refName
* @return commit, may be null
*/
public static RevCommit getRef(final Repository repository,
final String refName) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (refName == null)
throw new IllegalArgumentException(Assert.formatNotNull("Ref name"));
if (refName.length() == 0)
throw new IllegalArgumentException(
Assert.formatNotEmpty("Ref name"));
Ref ref;
try {
ref = repository.getRef(refName);
} catch (IOException e) {
throw new GitException(e, repository);
}
return ref != null ? lookupRef(repository, ref) : null;
}
/**
* Get the commit for the given reference.
*
* @param repository
* @param ref
* @return commit, may be null
*/
public static RevCommit getRef(final Repository repository, final Ref ref) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (ref == null)
throw new IllegalArgumentException(Assert.formatNotNull("Ref"));
return lookupRef(repository, ref);
}
/**
* Get all the commits that tags in the given repository reference.
*
* @param repository
* @return non-null but possibly empty collection of commits
*/
public static Collection<RevCommit> getTags(final Repository repository) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
final Collection<RevCommit> commits = new HashSet<RevCommit>();
final RevWalk walk = new RevWalk(repository);
final RefDatabase refDb = repository.getRefDatabase();
try {
getRefCommits(walk, refDb, R_TAGS, commits);
} catch (IOException e) {
throw new GitException(e, repository);
} finally {
walk.release();
}
return commits;
}
/**
* Get all the commits that branches in the given repository reference.
*
* @param repository
* @return non-null but possibly empty collection of commits
*/
public static Collection<RevCommit> getBranches(final Repository repository) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
final Collection<RevCommit> commits = new HashSet<RevCommit>();
final RevWalk walk = new RevWalk(repository);
final RefDatabase refDb = repository.getRefDatabase();
try {
getRefCommits(walk, refDb, R_HEADS, commits);
getRefCommits(walk, refDb, R_REMOTES, commits);
} catch (IOException e) {
throw new GitException(e, repository);
} finally {
walk.release();
}
return commits;
}
private static void getRefCommits(final RevWalk walk,
final RefDatabase refDb, final String prefix,
final Collection<RevCommit> commits) throws IOException {
for (Ref ref : refDb.getRefs(prefix).values()) {
final RevCommit commit = getRef(walk, ref);
if (commit != null)
commits.add(commit);
}
}
private static RevCommit lookupRef(final Repository repository,
final Ref ref) {
final RevWalk walk = new RevWalk(repository);
try {
return getRef(walk, ref);
} catch (IOException e) {
throw new GitException(e, repository);
} finally {
walk.release();
}
}
private static RevCommit getRef(final RevWalk walk, final Ref ref)
throws IOException {
ObjectId id = ref.getPeeledObjectId();
if (id == null)
id = ref.getObjectId();
return id != null ? walk.parseCommit(id) : null;
}
/**
* Resolve the revision string to a commit object id
*
* @param repository
* @param revision
* @return commit id
*/
protected static ObjectId resolve(final Repository repository,
final String revision) {
try {
return repository.resolve(revision);
} catch (IOException e) {
throw new GitException(e, repository);
}
}
/**
* Resolve the revision string to a commit object id.
* <p>
* A {@link GitException} will be thrown when the revision can not be
* resolved to an {@link ObjectId}
*
* @param repository
* @param revision
* @return commit id
*/
protected static ObjectId strictResolve(final Repository repository,
final String revision) {
final ObjectId resolved = resolve(repository, revision);
if (resolved == null)
throw new GitException(MessageFormat.format(
"Revision ''{0}'' could not be resolved", revision),
repository);
return resolved;
}
private static RevCommit walkToBase(final Repository repository,
final ObjectId... commits) {
final RevWalk walk = new RevWalk(repository);
walk.setRevFilter(MERGE_BASE);
try {
for (int i = 0; i < commits.length; i++)
walk.markStart(walk.parseCommit(commits[i]));
final RevCommit base = walk.next();
if (base != null)
walk.parseBody(base);
return base;
} catch (IOException e) {
throw new GitException(e, repository);
} finally {
walk.release();
}
}
/**
* Parse a commit from the repository
*
* @param repository
* @param commit
* @return commit
*/
protected static RevCommit parse(final Repository repository,
final ObjectId commit) {
final RevWalk walk = new RevWalk(repository);
walk.setRetainBody(true);
try {
return walk.parseCommit(commit);
} catch (IOException e) {
throw new GitException(e, repository);
} finally {
walk.release();
}
}
/**
* Parse a commit from the object reader
*
* @param repository
* @param reader
* @param commit
* @return commit
*/
protected static RevCommit parse(final Repository repository,
final ObjectReader reader, final ObjectId commit) {
final RevWalk walk = new RevWalk(reader);
walk.setRetainBody(true);
try {
return walk.parseCommit(commit);
} catch (IOException e) {
throw new GitException(e, repository);
}
}
/**
* Find the commit that last changed the given path starting at the commit
* that HEAD currently points to
*
* @param repository
* @param path
* @return commit
*/
public static RevCommit getLastCommit(final Repository repository,
final String path) {
return getLastCommit(repository, HEAD, path);
}
/**
* Find the commit that last changed the given path starting with the commit
* at the given revision
*
* @param repository
* @param revision
* @param path
* @return commit
*/
public static RevCommit getLastCommit(final Repository repository,
final String revision, final String path) {
if (repository == null)
throw new IllegalArgumentException(
Assert.formatNotNull("Repository"));
if (revision == null)
throw new IllegalArgumentException(Assert.formatNotNull("Revision"));
if (revision.length() == 0)
throw new IllegalArgumentException(
Assert.formatNotEmpty("Revision"));
if (path == null)
throw new IllegalArgumentException(Assert.formatNotNull("Path"));
if (path.length() == 0)
throw new IllegalArgumentException(Assert.formatNotEmpty("Path"));
final RevWalk walk = new RevWalk(repository);
walk.setRetainBody(true);
try {
walk.markStart(walk
.parseCommit(strictResolve(repository, revision)));
walk.setTreeFilter(PathFilterUtils.and(path));
return walk.next();
} catch (IOException e) {
throw new GitException(e, repository);
} finally {
walk.release();
}
}
}