| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.jackrabbit.oak.plugins.document; |
| |
| import java.lang.ref.ReferenceQueue; |
| import java.util.List; |
| import java.util.SortedSet; |
| import java.util.TreeSet; |
| import java.util.concurrent.CopyOnWriteArrayList; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import org.apache.jackrabbit.oak.plugins.document.Branch.BranchCommit; |
| import org.apache.jackrabbit.oak.plugins.document.Branch.BranchReference; |
| import org.apache.jackrabbit.oak.plugins.document.util.Utils; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| import static com.google.common.base.Preconditions.checkNotNull; |
| |
| /** |
| * <code>UnmergedBranches</code> contains all un-merged branches of a DocumentMK |
| * instance. |
| */ |
| class UnmergedBranches { |
| |
| private final Logger log = LoggerFactory.getLogger(getClass()); |
| |
| /** |
| * List of active branches. |
| */ |
| private final List<Branch> branches = new CopyOnWriteArrayList<Branch>(); |
| |
| /** |
| * Queue for {@link BranchReference} when the |
| * {@link DocumentNodeStoreBranch} associated with a {@link Branch} is only |
| * weakly reachable. |
| */ |
| private final ReferenceQueue<Object> queue = |
| new ReferenceQueue<Object>(); |
| |
| /** |
| * Set to <code>true</code> once initialized. |
| */ |
| private final AtomicBoolean initialized = new AtomicBoolean(false); |
| |
| /** |
| * Initialize with un-merged branches from <code>store</code> for this |
| * <code>clusterId</code>. |
| * |
| * @param store the document store. |
| * @param context the revision context. |
| */ |
| void init(DocumentStore store, RevisionContext context) { |
| if (!initialized.compareAndSet(false, true)) { |
| throw new IllegalStateException("already initialized"); |
| } |
| NodeDocument doc = store.find(Collection.NODES, Utils.getIdFromPath("/")); |
| if (doc == null) { |
| return; |
| } |
| int purgeCount = doc.purgeUncommittedRevisions(context); |
| if (purgeCount > 0) { |
| log.info("Purged [{}] uncommitted branch revision entries", purgeCount); |
| } |
| purgeCount = doc.purgeCollisionMarkers(context); |
| if (purgeCount > 0) { |
| log.info("Purged [{}] collision markers", purgeCount); |
| } |
| } |
| |
| /** |
| * Create a branch with an initial commit revision. |
| * |
| * @param base the base revision of the branch (must be a non-branch revision). |
| * @param initial the initial commit to the branch (must be a branch revision). |
| * @param guard an optional guard object controlling the life time of this |
| * branch. When {@code guard} becomes weakly reachable, the |
| * branch will at some point later be considered orphaned. |
| * Orphaned branches can be retrieved with |
| * {@link #pollOrphanedBranch()}. |
| * @return the branch. |
| * @throws IllegalArgumentException if {@code base} is a branch revision |
| * or {@code initial} is not a branch revision. |
| */ |
| @NotNull |
| Branch create(@NotNull RevisionVector base, |
| @NotNull Revision initial, |
| @Nullable Object guard) { |
| checkArgument(!checkNotNull(base).isBranch(), |
| "base is not a trunk revision: %s", base); |
| checkArgument(checkNotNull(initial).isBranch(), |
| "initial is not a branch revision: %s", initial); |
| SortedSet<Revision> commits = new TreeSet<Revision>(StableRevisionComparator.INSTANCE); |
| commits.add(initial); |
| Branch b = new Branch(commits, base, queue, guard); |
| branches.add(b); |
| return b; |
| } |
| |
| /** |
| * Returns the branch, which contains the given revision or <code>null</code> |
| * if there is no such branch. |
| * |
| * @param r a revision. |
| * @return the branch containing the given revision or <code>null</code>. |
| */ |
| @Nullable |
| Branch getBranch(@NotNull RevisionVector r) { |
| if (!r.isBranch()) { |
| return null; |
| } |
| Revision branchRev = r.getBranchRevision(); |
| for (Branch b : branches) { |
| if (b.containsCommit(branchRev)) { |
| return b; |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Returns {@code true} if the given revision is the base of an unmerged |
| * branch. |
| * |
| * @param r the base revision of a branch. |
| * @return {@code true} if such a branch exists, {@code false} otherwise. |
| */ |
| boolean isBranchBase(@NotNull RevisionVector r) { |
| if (!r.isBranch()) { |
| return false; |
| } |
| RevisionVector base = r.asTrunkRevision(); |
| for (Branch b : branches) { |
| if (b.getBase().equals(base)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Returns the branch commit with the given revision or {@code null} if |
| * it doesn't exists. |
| * |
| * @param r a revision. |
| * @return the branch commit or {@code null} if it doesn't exist. |
| */ |
| @Nullable |
| BranchCommit getBranchCommit(@NotNull Revision r) { |
| for (Branch b : branches) { |
| BranchCommit c = b.getCommit(r); |
| if (c != null) { |
| return c; |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Removes the given branch. |
| * @param b the branch to remove. |
| */ |
| void remove(Branch b) { |
| branches.remove(b); |
| } |
| |
| /** |
| * Count of currently unmerged branches |
| */ |
| int size(){ |
| return branches.size(); |
| } |
| |
| /** |
| * Polls for an orphaned branch. The implementation will remove the branch |
| * from the internal list of unmerged branches. |
| * |
| * @return an orphaned branch or {@code null} if there is none at this time. |
| */ |
| Branch pollOrphanedBranch() { |
| BranchReference ref = (BranchReference) queue.poll(); |
| if (ref != null) { |
| if (branches.remove(ref.getBranch())) { |
| return ref.getBranch(); |
| } |
| } |
| return null; |
| } |
| } |