Java tutorial
// Copyright (C) 2012 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.git; import com.google.common.collect.Lists; import com.google.gerrit.reviewdb.client.Change; import com.google.gerrit.reviewdb.client.PatchSet; import com.google.gerrit.reviewdb.client.PatchSetAncestor; import com.google.gerrit.reviewdb.client.PatchSetApproval; import com.google.gerrit.reviewdb.client.RevId; import com.google.gerrit.reviewdb.server.ReviewDb; import com.google.gerrit.server.ChangeUtil; import com.google.gerrit.server.extensions.events.GitReferenceUpdated; import com.google.gerrit.server.patch.PatchSetInfoFactory; import com.google.gwtorm.server.OrmException; import org.eclipse.jgit.lib.ObjectId; import org.eclipse.jgit.lib.PersonIdent; import org.eclipse.jgit.lib.RefUpdate; import org.eclipse.jgit.revwalk.RevCommit; import java.io.IOException; import java.sql.Timestamp; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; public class CherryPick extends SubmitStrategy { private final PatchSetInfoFactory patchSetInfoFactory; private final GitReferenceUpdated gitRefUpdated; private final Map<Change.Id, CodeReviewCommit> newCommits; CherryPick(final SubmitStrategy.Arguments args, final PatchSetInfoFactory patchSetInfoFactory, final GitReferenceUpdated gitRefUpdated) { super(args); this.patchSetInfoFactory = patchSetInfoFactory; this.gitRefUpdated = gitRefUpdated; this.newCommits = new HashMap<Change.Id, CodeReviewCommit>(); } @Override protected CodeReviewCommit _run(final CodeReviewCommit mergeTip, final List<CodeReviewCommit> toMerge) throws MergeException { CodeReviewCommit newMergeTip = mergeTip; while (!toMerge.isEmpty()) { final CodeReviewCommit n = toMerge.remove(0); try { if (newMergeTip == null) { // The branch is unborn. Take a fast-forward resolution to // create the branch. // newMergeTip = n; n.statusCode = CommitMergeStatus.CLEAN_MERGE; } else if (n.getParentCount() == 0) { // Refuse to merge a root commit into an existing branch, // we cannot obtain a delta for the cherry-pick to apply. // n.statusCode = CommitMergeStatus.CANNOT_CHERRY_PICK_ROOT; } else if (n.getParentCount() == 1) { // If there is only one parent, a cherry-pick can be done by // taking the delta relative to that one parent and redoing // that on the current merge tip. // newMergeTip = writeCherryPickCommit(mergeTip, n); if (newMergeTip != null) { newCommits.put(newMergeTip.patchsetId.getParentKey(), newMergeTip); } else { n.statusCode = CommitMergeStatus.PATH_CONFLICT; } } else { // There are multiple parents, so this is a merge commit. We // don't want to cherry-pick the merge as clients can't easily // rebase their history with that merge present and replaced // by an equivalent merge with a different first parent. So // instead behave as though MERGE_IF_NECESSARY was configured. // if (!args.mergeUtil.hasMissingDependencies(args.mergeSorter, n)) { if (args.rw.isMergedInto(newMergeTip, n)) { newMergeTip = n; } else { newMergeTip = args.mergeUtil.mergeOneCommit(args.myIdent, args.repo, args.rw, args.inserter, args.canMergeFlag, args.destBranch, newMergeTip, n); } final PatchSetApproval submitApproval = args.mergeUtil.markCleanMerges(args.rw, args.canMergeFlag, newMergeTip, args.alreadyAccepted); setRefLogIdent(submitApproval); } else { // One or more dependencies were not met. The status was // already marked on the commit so we have nothing further // to perform at this time. // } } } catch (IOException e) { throw new MergeException("Cannot merge " + n.name(), e); } catch (OrmException e) { throw new MergeException("Cannot merge " + n.name(), e); } } return newMergeTip; } private CodeReviewCommit writeCherryPickCommit(final CodeReviewCommit mergeTip, final CodeReviewCommit n) throws IOException, OrmException { args.rw.parseBody(n); final PatchSetApproval submitAudit = args.mergeUtil.getSubmitter(n.change.currentPatchSetId()); PersonIdent cherryPickCommitterIdent = null; if (submitAudit != null) { cherryPickCommitterIdent = args.identifiedUserFactory.create(submitAudit.getAccountId()) .newCommitterIdent(submitAudit.getGranted(), args.myIdent.getTimeZone()); } else { cherryPickCommitterIdent = args.myIdent; } final String cherryPickCmtMsg = args.mergeUtil.createCherryPickCommitMessage(n); final CodeReviewCommit newCommit = (CodeReviewCommit) args.mergeUtil.createCherryPickFromCommit(args.repo, args.inserter, mergeTip, n, cherryPickCommitterIdent, cherryPickCmtMsg, args.rw); if (newCommit == null) { return null; } PatchSet.Id id = ChangeUtil.nextPatchSetId(args.repo, n.change.currentPatchSetId()); final PatchSet ps = new PatchSet(id); ps.setCreatedOn(new Timestamp(System.currentTimeMillis())); ps.setUploader(submitAudit.getAccountId()); ps.setRevision(new RevId(newCommit.getId().getName())); insertAncestors(args.db, ps.getId(), newCommit); args.db.patchSets().insert(Collections.singleton(ps)); n.change.setCurrentPatchSet(patchSetInfoFactory.get(newCommit, ps.getId())); args.db.changes().update(Collections.singletonList(n.change)); final List<PatchSetApproval> approvals = Lists.newArrayList(); for (PatchSetApproval a : args.mergeUtil.getApprovalsForCommit(n)) { approvals.add(new PatchSetApproval(ps.getId(), a)); } args.db.patchSetApprovals().insert(approvals); final RefUpdate ru = args.repo.updateRef(ps.getRefName()); ru.setExpectedOldObjectId(ObjectId.zeroId()); ru.setNewObjectId(newCommit); ru.disableRefLog(); if (ru.update(args.rw) != RefUpdate.Result.NEW) { throw new IOException(String.format("Failed to create ref %s in %s: %s", ps.getRefName(), n.change.getDest().getParentKey().get(), ru.getResult())); } gitRefUpdated.fire(n.change.getProject(), ru); newCommit.copyFrom(n); newCommit.statusCode = CommitMergeStatus.CLEAN_PICK; newCommits.put(newCommit.patchsetId.getParentKey(), newCommit); setRefLogIdent(submitAudit); return newCommit; } private static void insertAncestors(ReviewDb db, PatchSet.Id id, RevCommit src) throws OrmException { final int cnt = src.getParentCount(); List<PatchSetAncestor> toInsert = new ArrayList<PatchSetAncestor>(cnt); for (int p = 0; p < cnt; p++) { PatchSetAncestor a; a = new PatchSetAncestor(new PatchSetAncestor.Id(id, p + 1)); a.setAncestorRevision(new RevId(src.getParent(p).getId().name())); toInsert.add(a); } db.patchSetAncestors().insert(toInsert); } @Override public Map<Change.Id, CodeReviewCommit> getNewCommits() { return newCommits; } @Override public boolean dryRun(final CodeReviewCommit mergeTip, final CodeReviewCommit toMerge) throws MergeException { return args.mergeUtil.canCherryPick(args.mergeSorter, args.repo, mergeTip, args.rw, toMerge); } }