Java tutorial
// Copyright (C) 2009 The Android Open Source Project // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. package com.google.gerrit.server; import static com.google.gerrit.server.query.change.ChangeData.asChanges; import com.google.common.base.Function; import com.google.common.base.Optional; import com.google.common.collect.ImmutableList; import com.google.common.collect.Ordering; import com.google.gerrit.common.TimeUtil; import com.google.gerrit.extensions.restapi.ResourceNotFoundException; import com.google.gerrit.reviewdb.client.Change; import com.google.gerrit.reviewdb.client.ChangeMessage; import com.google.gerrit.reviewdb.client.PatchSet; import com.google.gerrit.reviewdb.client.PatchSetAncestor; import com.google.gerrit.reviewdb.client.Project; import com.google.gerrit.reviewdb.client.RevId; import com.google.gerrit.reviewdb.server.ReviewDb; import com.google.gerrit.server.change.ChangeInserter; import com.google.gerrit.server.change.ChangeMessages; import com.google.gerrit.server.change.ChangeTriplet; import com.google.gerrit.server.events.CommitReceivedEvent; import com.google.gerrit.server.extensions.events.GitReferenceUpdated; import com.google.gerrit.server.git.GitRepositoryManager; import com.google.gerrit.server.git.validators.CommitValidationException; import com.google.gerrit.server.git.validators.CommitValidators; import com.google.gerrit.server.index.ChangeIndexer; import com.google.gerrit.server.mail.RevertedSender; import com.google.gerrit.server.project.ChangeControl; import com.google.gerrit.server.project.InvalidChangeOperationException; import com.google.gerrit.server.project.NoSuchChangeException; import com.google.gerrit.server.project.RefControl; import com.google.gerrit.server.query.change.InternalChangeQuery; import com.google.gerrit.server.ssh.SshInfo; import com.google.gerrit.server.util.IdGenerator; import com.google.gerrit.server.util.MagicBranch; import com.google.gwtorm.server.OrmConcurrencyException; import com.google.gwtorm.server.OrmException; import com.google.inject.Inject; import com.google.inject.Provider; import com.google.inject.Singleton; import org.eclipse.jgit.errors.IncorrectObjectTypeException; import org.eclipse.jgit.errors.MissingObjectException; import org.eclipse.jgit.errors.RepositoryNotFoundException; import org.eclipse.jgit.lib.BatchRefUpdate; import org.eclipse.jgit.lib.CommitBuilder; import org.eclipse.jgit.lib.NullProgressMonitor; import org.eclipse.jgit.lib.ObjectId; import org.eclipse.jgit.lib.ObjectInserter; import org.eclipse.jgit.lib.PersonIdent; import org.eclipse.jgit.lib.Ref; import org.eclipse.jgit.lib.RefDatabase; import org.eclipse.jgit.lib.RefUpdate; import org.eclipse.jgit.lib.Repository; import org.eclipse.jgit.revwalk.RevCommit; import org.eclipse.jgit.revwalk.RevWalk; import org.eclipse.jgit.transport.ReceiveCommand; import org.eclipse.jgit.util.ChangeIdUtil; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.IOException; import java.text.MessageFormat; import java.util.ArrayList; import java.util.Collections; import java.util.List; import java.util.Map; @Singleton public class ChangeUtil { private static final Object uuidLock = new Object(); private static final int SEED = 0x2418e6f9; private static int uuidPrefix; private static int uuidSeq; private static final int SUBJECT_MAX_LENGTH = 80; private static final String SUBJECT_CROP_APPENDIX = "..."; private static final int SUBJECT_CROP_RANGE = 10; private static final Logger log = LoggerFactory.getLogger(ChangeUtil.class); public static final Function<PatchSet, Integer> TO_PS_ID = new Function<PatchSet, Integer>() { @Override public Integer apply(PatchSet in) { return in.getId().get(); } }; public static final Ordering<PatchSet> PS_ID_ORDER = Ordering.natural().onResultOf(TO_PS_ID); /** * Generate a new unique identifier for change message entities. * * @param db the database connection, used to increment the change message * allocation sequence. * @return the new unique identifier. * @throws OrmException the database couldn't be incremented. */ public static String messageUUID(ReviewDb db) throws OrmException { int p; int s; synchronized (uuidLock) { if (uuidSeq == 0) { uuidPrefix = db.nextChangeMessageId(); uuidSeq = Integer.MAX_VALUE; } p = uuidPrefix; s = uuidSeq--; } String u = IdGenerator.format(IdGenerator.mix(SEED, p)); String l = IdGenerator.format(IdGenerator.mix(p, s)); return u + '_' + l; } public static void touch(Change change, ReviewDb db) throws OrmException { try { updated(change); db.changes().update(Collections.singleton(change)); } catch (OrmConcurrencyException e) { // Ignore a concurrent update, we just wanted to tag it as newer. } } public static void bumpRowVersionNotLastUpdatedOn(Change.Id id, ReviewDb db) throws OrmException { // Empty update of Change to bump rowVersion, changing its ETag. Change c = db.changes().get(id); if (c != null) { db.changes().update(Collections.singleton(c)); } } public static void updated(Change c) { c.setLastUpdatedOn(TimeUtil.nowTs()); } public static void insertAncestors(ReviewDb db, PatchSet.Id id, RevCommit src) throws OrmException { int cnt = src.getParentCount(); List<PatchSetAncestor> toInsert = new ArrayList<>(cnt); for (int p = 0; p < cnt; p++) { PatchSetAncestor a = new PatchSetAncestor(new PatchSetAncestor.Id(id, p + 1)); a.setAncestorRevision(new RevId(src.getParent(p).getId().getName())); toInsert.add(a); } db.patchSetAncestors().insert(toInsert); } public static PatchSet.Id nextPatchSetId(Map<String, Ref> allRefs, PatchSet.Id id) { PatchSet.Id next = nextPatchSetId(id); while (allRefs.containsKey(next.toRefName())) { next = nextPatchSetId(next); } return next; } public static PatchSet.Id nextPatchSetId(Repository git, PatchSet.Id id) throws IOException { return nextPatchSetId(git.getRefDatabase().getRefs(RefDatabase.ALL), id); } public static String cropSubject(String subject) { if (subject.length() > SUBJECT_MAX_LENGTH) { int maxLength = SUBJECT_MAX_LENGTH - SUBJECT_CROP_APPENDIX.length(); for (int cropPosition = maxLength; cropPosition > maxLength - SUBJECT_CROP_RANGE; cropPosition--) { if (Character.isWhitespace(subject.charAt(cropPosition - 1))) { return subject.substring(0, cropPosition) + SUBJECT_CROP_APPENDIX; } } return subject.substring(0, maxLength) + SUBJECT_CROP_APPENDIX; } return subject; } private final Provider<CurrentUser> userProvider; private final CommitValidators.Factory commitValidatorsFactory; private final Provider<ReviewDb> db; private final Provider<InternalChangeQuery> queryProvider; private final RevertedSender.Factory revertedSenderFactory; private final ChangeInserter.Factory changeInserterFactory; private final GitRepositoryManager gitManager; private final GitReferenceUpdated gitRefUpdated; private final ChangeIndexer indexer; @Inject ChangeUtil(Provider<CurrentUser> userProvider, CommitValidators.Factory commitValidatorsFactory, Provider<ReviewDb> db, Provider<InternalChangeQuery> queryProvider, RevertedSender.Factory revertedSenderFactory, ChangeInserter.Factory changeInserterFactory, GitRepositoryManager gitManager, GitReferenceUpdated gitRefUpdated, ChangeIndexer indexer) { this.userProvider = userProvider; this.commitValidatorsFactory = commitValidatorsFactory; this.db = db; this.queryProvider = queryProvider; this.revertedSenderFactory = revertedSenderFactory; this.changeInserterFactory = changeInserterFactory; this.gitManager = gitManager; this.gitRefUpdated = gitRefUpdated; this.indexer = indexer; } public Change.Id revert(ChangeControl ctl, PatchSet.Id patchSetId, String message, PersonIdent myIdent, SshInfo sshInfo) throws NoSuchChangeException, OrmException, MissingObjectException, IncorrectObjectTypeException, IOException, InvalidChangeOperationException { Change.Id changeId = patchSetId.getParentKey(); PatchSet patch = db.get().patchSets().get(patchSetId); if (patch == null) { throw new NoSuchChangeException(changeId); } Change changeToRevert = db.get().changes().get(changeId); Project.NameKey project = ctl.getChange().getProject(); try (Repository git = gitManager.openRepository(project); RevWalk revWalk = new RevWalk(git)) { RevCommit commitToRevert = revWalk.parseCommit(ObjectId.fromString(patch.getRevision().get())); PersonIdent authorIdent = user().newCommitterIdent(myIdent.getWhen(), myIdent.getTimeZone()); RevCommit parentToCommitToRevert = commitToRevert.getParent(0); revWalk.parseHeaders(parentToCommitToRevert); CommitBuilder revertCommitBuilder = new CommitBuilder(); revertCommitBuilder.addParentId(commitToRevert); revertCommitBuilder.setTreeId(parentToCommitToRevert.getTree()); revertCommitBuilder.setAuthor(authorIdent); revertCommitBuilder.setCommitter(authorIdent); if (message == null) { message = MessageFormat.format(ChangeMessages.get().revertChangeDefaultMessage, changeToRevert.getSubject(), patch.getRevision().get()); } ObjectId computedChangeId = ChangeIdUtil.computeChangeId(parentToCommitToRevert.getTree(), commitToRevert, authorIdent, myIdent, message); revertCommitBuilder.setMessage(ChangeIdUtil.insertId(message, computedChangeId, true)); RevCommit revertCommit; try (ObjectInserter oi = git.newObjectInserter()) { ObjectId id = oi.insert(revertCommitBuilder); oi.flush(); revertCommit = revWalk.parseCommit(id); } RefControl refControl = ctl.getRefControl(); Change change = new Change(new Change.Key("I" + computedChangeId.name()), new Change.Id(db.get().nextChangeId()), user().getAccountId(), changeToRevert.getDest(), TimeUtil.nowTs()); change.setTopic(changeToRevert.getTopic()); ChangeInserter ins = changeInserterFactory.create(refControl.getProjectControl(), change, revertCommit); PatchSet ps = ins.getPatchSet(); String ref = refControl.getRefName(); String cmdRef = MagicBranch.NEW_PUBLISH_CHANGE + ref.substring(ref.lastIndexOf('/') + 1); CommitReceivedEvent commitReceivedEvent = new CommitReceivedEvent( new ReceiveCommand(ObjectId.zeroId(), revertCommit.getId(), cmdRef), refControl.getProjectControl().getProject(), refControl.getRefName(), revertCommit, user()); try { commitValidatorsFactory.create(refControl, sshInfo, git) .validateForGerritCommits(commitReceivedEvent); } catch (CommitValidationException e) { throw new InvalidChangeOperationException(e.getMessage()); } RefUpdate ru = git.updateRef(ps.getRefName()); ru.setExpectedOldObjectId(ObjectId.zeroId()); ru.setNewObjectId(revertCommit); ru.disableRefLog(); if (ru.update(revWalk) != RefUpdate.Result.NEW) { throw new IOException(String.format("Failed to create ref %s in %s: %s", ps.getRefName(), change.getDest().getParentKey().get(), ru.getResult())); } ChangeMessage cmsg = new ChangeMessage(new ChangeMessage.Key(changeId, messageUUID(db.get())), user().getAccountId(), TimeUtil.nowTs(), patchSetId); StringBuilder msgBuf = new StringBuilder(); msgBuf.append("Patch Set ").append(patchSetId.get()).append(": Reverted"); msgBuf.append("\n\n"); msgBuf.append("This patchset was reverted in change: ").append(change.getKey().get()); cmsg.setMessage(msgBuf.toString()); ins.setMessage(cmsg).insert(); try { RevertedSender cm = revertedSenderFactory.create(change.getId()); cm.setFrom(user().getAccountId()); cm.setChangeMessage(cmsg); cm.send(); } catch (Exception err) { log.error("Cannot send email for revert change " + change.getId(), err); } return change.getId(); } catch (RepositoryNotFoundException e) { throw new NoSuchChangeException(changeId, e); } } public String getMessage(Change change) throws NoSuchChangeException, OrmException, MissingObjectException, IncorrectObjectTypeException, IOException { Change.Id changeId = change.getId(); PatchSet ps = db.get().patchSets().get(change.currentPatchSetId()); if (ps == null) { throw new NoSuchChangeException(changeId); } try (Repository git = gitManager.openRepository(change.getProject()); RevWalk revWalk = new RevWalk(git)) { RevCommit commit = revWalk.parseCommit(ObjectId.fromString(ps.getRevision().get())); return commit.getFullMessage(); } catch (RepositoryNotFoundException e) { throw new NoSuchChangeException(changeId, e); } } public void deleteDraftChange(Change change) throws NoSuchChangeException, OrmException, IOException { Change.Id changeId = change.getId(); if (change.getStatus() != Change.Status.DRAFT) { throw new NoSuchChangeException(changeId); } ReviewDb db = this.db.get(); db.changes().beginTransaction(change.getId()); try { List<PatchSet> patchSets = db.patchSets().byChange(changeId).toList(); for (PatchSet ps : patchSets) { if (!ps.isDraft()) { throw new NoSuchChangeException(changeId); } db.accountPatchReviews().delete(db.accountPatchReviews().byPatchSet(ps.getId())); } // No need to delete from notedb; draft patch sets will be filtered out. db.patchComments().delete(db.patchComments().byChange(changeId)); db.patchSetApprovals().delete(db.patchSetApprovals().byChange(changeId)); db.patchSetAncestors().delete(db.patchSetAncestors().byChange(changeId)); db.patchSets().delete(patchSets); db.changeMessages().delete(db.changeMessages().byChange(changeId)); db.starredChanges().delete(db.starredChanges().byChange(changeId)); db.changes().delete(Collections.singleton(change)); // Delete all refs at once. try (Repository repo = gitManager.openRepository(change.getProject()); RevWalk rw = new RevWalk(repo)) { String prefix = new PatchSet.Id(changeId, 1).toRefName(); prefix = prefix.substring(0, prefix.length() - 1); BatchRefUpdate ru = repo.getRefDatabase().newBatchUpdate(); for (Ref ref : repo.getRefDatabase().getRefs(prefix).values()) { ru.addCommand(new ReceiveCommand(ref.getObjectId(), ObjectId.zeroId(), ref.getName())); } ru.execute(rw, NullProgressMonitor.INSTANCE); for (ReceiveCommand cmd : ru.getCommands()) { if (cmd.getResult() != ReceiveCommand.Result.OK) { throw new IOException("failed: " + cmd + ": " + cmd.getResult()); } } } db.commit(); indexer.delete(change.getId()); } finally { db.rollback(); } } public void deleteOnlyDraftPatchSet(PatchSet patch, Change change) throws NoSuchChangeException, OrmException, IOException { PatchSet.Id patchSetId = patch.getId(); if (!patch.isDraft()) { throw new NoSuchChangeException(patchSetId.getParentKey()); } try (Repository repo = gitManager.openRepository(change.getProject())) { RefUpdate update = repo.updateRef(patch.getRefName()); update.setForceUpdate(true); update.disableRefLog(); switch (update.delete()) { case NEW: case FAST_FORWARD: case FORCED: case NO_CHANGE: // Successful deletion. break; default: throw new IOException("Failed to delete ref " + patch.getRefName() + " in " + repo.getDirectory() + ": " + update.getResult()); } gitRefUpdated.fire(change.getProject(), update, ReceiveCommand.Type.DELETE); } deleteOnlyDraftPatchSetPreserveRef(this.db.get(), patch); } /** * Find changes matching the given identifier. * * @param id change identifier, either a numeric ID, a Change-Id, or * project~branch~id triplet. * @return all matching changes, even if they are not visible to the current * user. */ public List<Change> findChanges(String id) throws OrmException, ResourceNotFoundException { // Try legacy id if (id.matches("^[1-9][0-9]*$")) { Change c = db.get().changes().get(Change.Id.parse(id)); if (c != null) { return ImmutableList.of(c); } return Collections.emptyList(); } // Try isolated changeId if (!id.contains("~")) { return asChanges(queryProvider.get().byKeyPrefix(id)); } // Try change triplet Optional<ChangeTriplet> triplet = ChangeTriplet.parse(id); if (triplet.isPresent()) { return asChanges(queryProvider.get().byBranchKey(triplet.get().branch(), triplet.get().id())); } throw new ResourceNotFoundException(id); } private IdentifiedUser user() { return (IdentifiedUser) userProvider.get(); } private static void deleteOnlyDraftPatchSetPreserveRef(ReviewDb db, PatchSet patch) throws NoSuchChangeException, OrmException { PatchSet.Id patchSetId = patch.getId(); if (!patch.isDraft()) { throw new NoSuchChangeException(patchSetId.getParentKey()); } db.accountPatchReviews().delete(db.accountPatchReviews().byPatchSet(patchSetId)); db.changeMessages().delete(db.changeMessages().byPatchSet(patchSetId)); // No need to delete from notedb; draft patch sets will be filtered out. db.patchComments().delete(db.patchComments().byPatchSet(patchSetId)); db.patchSetApprovals().delete(db.patchSetApprovals().byPatchSet(patchSetId)); db.patchSetAncestors().delete(db.patchSetAncestors().byPatchSet(patchSetId)); db.patchSets().delete(Collections.singleton(patch)); } public static PatchSet.Id nextPatchSetId(PatchSet.Id id) { return new PatchSet.Id(id.getParentKey(), id.get() + 1); } }