/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
* or http://forgerock.org/license/CDDLv1.0.html.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at legal-notices/CDDLv1_0.txt.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information:
* Portions Copyright [yyyy] [name of copyright owner]
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* CDDL HEADER END
*
*
* Copyright 2006-2008 Sun Microsystems, Inc.
* Portions Copyright 2014-2015 ForgeRock AS
*/
package org.opends.server.backends.pluggable;
import static org.opends.server.backends.pluggable.EntryIDSet.*;
import java.util.Map;
import java.util.Map.Entry;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.TreeSet;
import org.forgerock.opendj.ldap.ByteString;
import org.forgerock.util.Reject;
import org.opends.server.backends.pluggable.spi.StorageRuntimeException;
import org.opends.server.backends.pluggable.spi.WriteableTransaction;
import org.opends.server.types.DirectoryException;
/**
* A buffered index is used to buffer multiple reads or writes to the
* same index key into a single read or write.
* <p>
* It can only be used to buffer multiple reads and writes under
* the same transaction. The transaction may be null if it is known
* that there are no other concurrent updates to the index.
*/
class IndexBuffer
{
/** Internal interface for IndexBuffer implementor. */
private interface IndexBufferImplementor
{
void flush(WriteableTransaction txn) throws StorageRuntimeException, DirectoryException;
void writeTrustState(WriteableTransaction txn) throws StorageRuntimeException;
void put(Index index, ByteString key, EntryID entryID);
void put(VLVIndex index, ByteString sortKey);
void remove(VLVIndex index, ByteString sortKey);
void remove(Index index, ByteString key, EntryID entryID);
void reset();
}
/**
* A buffered index is used to buffer multiple reads or writes to the same index key into a single read or write.
* <p>
* It can only be used to buffer multiple reads and writes under the same transaction. The transaction may be null if
* it is known that there are no other concurrent updates to the index.
*/
private static final class DefaultIndexBuffer implements IndexBufferImplementor
{
/**
* The buffered records stored as a map from the record key to the buffered value for that key for each index.
* <p>
* The map is sorted by {@link TreeName}s to establish a deterministic iteration order (see {@link AbstractTree}).
* This prevents potential deadlock for db having pessimistic lock strategy (e.g.: JE).
*/
private final SortedMap<Index, SortedMap<ByteString, BufferedIndexValues>> bufferedIndexes = new TreeMap<>();
/**
* The buffered records stored as a set of buffered VLV values for each index.
* <p>
* The map is sorted by {@link TreeName}s to establish a deterministic iteration order (see {@link AbstractTree}).
* This prevents potential deadlock for db having pessimistic lock strategy (e.g.: JE).
*/
private final SortedMap<VLVIndex, BufferedVLVIndexValues> bufferedVLVIndexes = new TreeMap<>();
/**
* A simple class representing a pair of added and deleted indexed IDs. Initially both addedIDs and deletedIDs are
* {@code null} indicating that that the whole record should be deleted.
*/
private static class BufferedIndexValues
{
private EntryIDSet addedEntryIDs;
private EntryIDSet deletedEntryIDs;
void addEntryID(EntryID entryID)
{
if (!remove(deletedEntryIDs, entryID))
{
if (this.addedEntryIDs == null)
{
this.addedEntryIDs = newDefinedSet();
}
this.addedEntryIDs.add(entryID);
}
}
void deleteEntryID(EntryID entryID)
{
if (!remove(addedEntryIDs, entryID))
{
if (this.deletedEntryIDs == null)
{
this.deletedEntryIDs = newDefinedSet();
}
this.deletedEntryIDs.add(entryID);
}
}
private static boolean remove(EntryIDSet entryIDs, EntryID entryID)
{
return entryIDs != null ? entryIDs.remove(entryID) : false;
}
}
/** A simple class representing a pair of added and deleted VLV values. */
private static class BufferedVLVIndexValues
{
private TreeSet<ByteString> addedSortKeys;
private TreeSet<ByteString> deletedSortKeys;
void addSortKey(ByteString sortKey)
{
if (!remove(deletedSortKeys, sortKey))
{
if (addedSortKeys == null)
{
addedSortKeys = new TreeSet<>();
}
addedSortKeys.add(sortKey);
}
}
void deleteSortKey(ByteString sortKey)
{
if (!remove(addedSortKeys, sortKey))
{
if (deletedSortKeys == null)
{
deletedSortKeys = new TreeSet<>();
}
deletedSortKeys.add(sortKey);
}
}
private static boolean remove(TreeSet<ByteString> sortKeys, ByteString sortKey)
{
return sortKeys != null ? sortKeys.remove(sortKey) : false;
}
}
private BufferedVLVIndexValues createOrGetBufferedVLVIndexValues(VLVIndex vlvIndex)
{
BufferedVLVIndexValues bufferedValues = bufferedVLVIndexes.get(vlvIndex);
if (bufferedValues == null)
{
bufferedValues = new BufferedVLVIndexValues();
bufferedVLVIndexes.put(vlvIndex, bufferedValues);
}
return bufferedValues;
}
private BufferedIndexValues createOrGetBufferedIndexValues(Index index, ByteString keyBytes)
{
Map<ByteString, BufferedIndexValues> bufferedOperations = createOrGetBufferedOperations(index);
BufferedIndexValues values = bufferedOperations.get(keyBytes);
if (values == null)
{
values = new BufferedIndexValues();
bufferedOperations.put(keyBytes, values);
}
return values;
}
private Map<ByteString, BufferedIndexValues> createOrGetBufferedOperations(Index index)
{
SortedMap<ByteString, BufferedIndexValues> bufferedOperations = bufferedIndexes.get(index);
if (bufferedOperations == null)
{
bufferedOperations = new TreeMap<>();
bufferedIndexes.put(index, bufferedOperations);
}
return bufferedOperations;
}
@Override
public void flush(WriteableTransaction txn) throws StorageRuntimeException, DirectoryException
{
// Indexes are stored in sorted map to prevent deadlock during flush with DB using pessimistic lock strategies.
for (Entry<Index, SortedMap<ByteString, BufferedIndexValues>> entry : bufferedIndexes.entrySet())
{
flushIndex(entry.getKey(), txn, entry.getValue());
}
for (Entry<VLVIndex, BufferedVLVIndexValues> entry : bufferedVLVIndexes.entrySet())
{
entry.getKey().updateIndex(txn, entry.getValue().addedSortKeys, entry.getValue().deletedSortKeys);
}
}
@Override
public void writeTrustState(WriteableTransaction txn)
{
// Indexes cache the index trust flag. Ensure that the cached value is written into the db.
for (Index index : bufferedIndexes.keySet())
{
index.setTrusted(txn, index.isTrusted());
}
for (VLVIndex index : bufferedVLVIndexes.keySet())
{
index.setTrusted(txn, index.isTrusted());
}
}
@Override
public void put(Index index, ByteString key, EntryID entryID)
{
createOrGetBufferedIndexValues(index, key).addEntryID(entryID);
}
@Override
public void put(VLVIndex index, ByteString sortKey)
{
createOrGetBufferedVLVIndexValues(index).addSortKey(sortKey);
}
@Override
public void remove(VLVIndex index, ByteString sortKey)
{
createOrGetBufferedVLVIndexValues(index).deleteSortKey(sortKey);
}
@Override
public void remove(Index index, ByteString key, EntryID entryID)
{
createOrGetBufferedIndexValues(index, key).deleteEntryID(entryID);
}
private static void flushIndex(Index index, WriteableTransaction txn,
Map<ByteString, BufferedIndexValues> bufferedValues)
{
for (Entry<ByteString, BufferedIndexValues> entry : bufferedValues.entrySet())
{
final BufferedIndexValues values = entry.getValue();
index.update(txn, entry.getKey(), values.deletedEntryIDs, values.addedEntryIDs);
}
}
@Override
public void reset()
{
bufferedIndexes.clear();
bufferedVLVIndexes.clear();
}
}
/**
* IndexBuffer used during import which actually doesn't buffer modifications but forward those directly to the
* supplied {@link WriteableTransaction}.
*/
private static final class ImportIndexBuffer implements IndexBufferImplementor
{
private final WriteableTransaction txn;
private final EntryID expectedEntryID;
private final ByteString encodedEntryID;
ImportIndexBuffer(WriteableTransaction txn, EntryID expectedEntryID)
{
this.txn = txn;
this.expectedEntryID = expectedEntryID;
this.encodedEntryID = CODEC_V2.encode(EntryIDSet.newDefinedSet(expectedEntryID.longValue()));
}
@Override
public void put(Index index, ByteString key, EntryID entryID)
{
Reject.ifFalse(this.expectedEntryID.equals(entryID), "Unexpected entryID");
txn.put(index.getName(), key, encodedEntryID);
}
@Override
public void put(VLVIndex index, ByteString sortKey)
{
txn.put(index.getName(), sortKey, index.toValue());
}
@Override
public void flush(WriteableTransaction txn) throws StorageRuntimeException, DirectoryException
{
// Nothing to do
}
@Override
public void writeTrustState(WriteableTransaction txn)
{
// Nothing to do
}
@Override
public void remove(VLVIndex index, ByteString sortKey)
{
throw new UnsupportedOperationException();
}
@Override
public void remove(Index index, ByteString key, EntryID entryID)
{
throw new UnsupportedOperationException();
}
@Override
public void reset()
{
throw new UnsupportedOperationException();
}
}
private final IndexBufferImplementor impl;
static IndexBuffer newImportIndexBuffer(WriteableTransaction txn, EntryID entryID)
{
return new IndexBuffer(new ImportIndexBuffer(txn, entryID));
}
public IndexBuffer()
{
this(new DefaultIndexBuffer());
}
private IndexBuffer(IndexBufferImplementor impl)
{
this.impl = impl;
}
/**
* Flush the buffered index changes to storage.
*
* @param txn
* a non null transaction
* @throws StorageRuntimeException
* If an error occurs in the storage.
* @throws DirectoryException
* If a Directory Server error occurs.
*/
void flush(WriteableTransaction txn) throws StorageRuntimeException, DirectoryException
{
impl.flush(txn);
}
/**
* Indexes might cache their trust state. This ensure that the cached state is persisted into the database.
*
* @param txn
* a non null transaction
* @throws StorageRuntimeException
* If an error occurs in the storage.
*/
void writeTrustState(WriteableTransaction txn)
{
impl.writeTrustState(txn);
}
void put(Index index, ByteString key, EntryID entryID)
{
impl.put(index, key, entryID);
}
void put(VLVIndex index, ByteString sortKey)
{
impl.put(index, sortKey);
}
void remove(VLVIndex index, ByteString sortKey)
{
impl.remove(index, sortKey);
}
void remove(Index index, ByteString key, EntryID entryID)
{
impl.remove(index, key, entryID);
}
void reset()
{
impl.reset();
}
}