| /* |
| * 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 static com.google.common.base.Preconditions.checkNotNull; |
| import static com.google.common.collect.Iterables.filter; |
| import static com.google.common.collect.Iterables.transform; |
| import static java.util.AbstractMap.SimpleImmutableEntry; |
| |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.TreeMap; |
| |
| import com.google.common.base.Function; |
| import com.google.common.base.Predicates; |
| import com.google.common.collect.AbstractIterator; |
| import com.google.common.collect.Iterators; |
| import com.google.common.collect.PeekingIterator; |
| 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; |
| |
| /** |
| * The revision history for a given property. The history may span multiple |
| * previous documents. |
| */ |
| class PropertyHistory implements Iterable<NodeDocument> { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(PropertyHistory.class); |
| |
| private final NodeDocument doc; |
| private final String property; |
| // path of the main document |
| private final String mainPath; |
| |
| public PropertyHistory(@NotNull NodeDocument doc, |
| @NotNull String property) { |
| this.doc = checkNotNull(doc); |
| this.property = checkNotNull(property); |
| this.mainPath = doc.getMainPath(); |
| } |
| |
| @Override |
| public Iterator<NodeDocument> iterator() { |
| return ensureOrder(filter(transform(doc.getPreviousRanges().entrySet(), |
| new Function<Map.Entry<Revision, Range>, Map.Entry<Revision, NodeDocument>>() { |
| @Nullable |
| @Override |
| public Map.Entry<Revision, NodeDocument> apply(Map.Entry<Revision, Range> input) { |
| Revision r = input.getKey(); |
| int h = input.getValue().height; |
| String prevId = Utils.getPreviousIdFor(mainPath, r, h); |
| NodeDocument prev = doc.getPreviousDocument(prevId); |
| if (prev == null) { |
| LOG.debug("Document with previous revisions not found: " + prevId); |
| return null; |
| } |
| return new SimpleImmutableEntry<Revision, NodeDocument>(r, prev); |
| } |
| }), Predicates.notNull())); |
| } |
| |
| /** |
| * Ensures the order of docs is correct with respect to the highest revision |
| * for each ValueMap for the given property. |
| * |
| * @param docs the docs to order. |
| * @return the docs in the correct order. |
| */ |
| private Iterator<NodeDocument> ensureOrder(final Iterable<Map.Entry<Revision, NodeDocument>> docs) { |
| return new AbstractIterator<NodeDocument>() { |
| PeekingIterator<Map.Entry<Revision, NodeDocument>> input |
| = Iterators.peekingIterator(docs.iterator()); |
| TreeMap<Revision, NodeDocument> queue = |
| new TreeMap<Revision, NodeDocument>(StableRevisionComparator.INSTANCE); |
| |
| @Override |
| protected NodeDocument computeNext() { |
| refillQueue(); |
| if (queue.isEmpty()) { |
| return endOfData(); |
| } else { |
| return queue.remove(queue.lastKey()); |
| } |
| } |
| |
| /** |
| * Refill the queue until the highest entry in the queue is higher |
| * than the peeked entry from the input iterator. |
| */ |
| private void refillQueue() { |
| for (;;) { |
| // the doc to enqueue |
| NodeDocument doc; |
| if (queue.isEmpty()) { |
| if (input.hasNext()) { |
| doc = input.next().getValue(); |
| } else { |
| // no more input -> done |
| return; |
| } |
| } else { |
| // peek first and compare with queue |
| if (input.hasNext()) { |
| if (queue.comparator().compare(queue.lastKey(), input.peek().getKey()) < 0) { |
| doc = input.next().getValue(); |
| } else { |
| // top of queue rev is higher than input -> done |
| return; |
| } |
| } else { |
| // no more input -> done |
| return; |
| } |
| } |
| // check if the revision is actually in there |
| if (doc != null) { |
| Map<Revision, String> values = doc.getValueMap(property); |
| Iterator<Revision> revs = values.keySet().iterator(); |
| if (revs.hasNext()) { |
| // put into queue with first (highest) revision |
| // from value map |
| queue.put(revs.next(), doc); |
| } |
| } |
| } |
| } |
| }; |
| } |
| } |