/*
* 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.segment.memory;
import static org.apache.jackrabbit.oak.plugins.memory.EmptyNodeState.EMPTY_NODE;
import java.nio.ByteBuffer;
import java.util.concurrent.ConcurrentMap;
import javax.annotation.Nonnull;
import org.apache.jackrabbit.oak.api.Blob;
import org.apache.jackrabbit.oak.plugins.segment.Segment;
import org.apache.jackrabbit.oak.plugins.segment.SegmentId;
import org.apache.jackrabbit.oak.plugins.segment.SegmentNotFoundException;
import org.apache.jackrabbit.oak.plugins.segment.SegmentTracker;
import org.apache.jackrabbit.oak.plugins.segment.SegmentNodeState;
import org.apache.jackrabbit.oak.plugins.segment.SegmentStore;
import org.apache.jackrabbit.oak.plugins.segment.SegmentWriter;
import org.apache.jackrabbit.oak.spi.blob.BlobStore;
import org.apache.jackrabbit.oak.spi.state.NodeBuilder;
import org.apache.jackrabbit.oak.spi.state.NodeState;
import com.google.common.collect.Maps;
/**
* A store used for in-memory operations.
*/
public class MemoryStore implements SegmentStore {
private final SegmentTracker tracker = new SegmentTracker(this);
private SegmentNodeState head;
private final ConcurrentMap<SegmentId, Segment> segments =
Maps.newConcurrentMap();
public MemoryStore(NodeState root) {
NodeBuilder builder = EMPTY_NODE.builder();
builder.setChildNode("root", root);
SegmentWriter writer = tracker.getWriter();
this.head = writer.writeNode(builder.getNodeState());
writer.flush();
}
public MemoryStore() {
this(EMPTY_NODE);
}
@Override
public SegmentTracker getTracker() {
return tracker;
}
@Override
public synchronized SegmentNodeState getHead() {
return head;
}
@Override
public synchronized boolean setHead(SegmentNodeState base, SegmentNodeState head) {
if (this.head.getRecordId().equals(base.getRecordId())) {
this.head = head;
return true;
} else {
return false;
}
}
@Override
public boolean containsSegment(SegmentId id) {
return id.getTracker() == tracker || segments.containsKey(id);
}
@Override @Nonnull
public Segment readSegment(SegmentId id) {
Segment segment = segments.get(id);
if (segment != null) {
return segment;
}
throw new SegmentNotFoundException(id);
}
@Override
public void writeSegment(
SegmentId id, byte[] data, int offset, int length) {
ByteBuffer buffer = ByteBuffer.allocate(length);
buffer.put(data, offset, length);
buffer.rewind();
Segment segment = new Segment(tracker, id, buffer);
if (segments.putIfAbsent(id, segment) != null) {
throw new IllegalStateException("Segment override: " + id);
}
}
@Override
public void close() {
}
@Override
public Blob readBlob(String reference) {
return null;
}
@Override
public BlobStore getBlobStore() {
return null;
}
@Override
public void gc() {
System.gc();
segments.keySet().retainAll(tracker.getReferencedSegmentIds());
}
}