// Copyright 2017 JanusGraph Authors
//
// 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 org.janusgraph.diskstorage.keycolumnvalue.keyvalue;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableMap;
import org.janusgraph.diskstorage.BackendException;
import org.janusgraph.diskstorage.Entry;
import org.janusgraph.diskstorage.StaticBuffer;
import org.janusgraph.diskstorage.BaseTransactionConfig;
import org.janusgraph.diskstorage.StoreMetaData;
import org.janusgraph.diskstorage.keycolumnvalue.*;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Wraps a {@link OrderedKeyValueStoreManager} and exposes it as a {@link KeyColumnValueStoreManager}.
* <p/>
* An optional mapping of key-length can be defined if it is known that the {@link KeyColumnValueStore} of a given
* name has a static key length. See {@link OrderedKeyValueStoreAdapter} for more information.
*
* @author Matthias Bröcheler (me@matthiasb.com);
*/
public class OrderedKeyValueStoreManagerAdapter implements KeyColumnValueStoreManager {
private final OrderedKeyValueStoreManager manager;
private final ImmutableMap<String, Integer> keyLengths;
private final Map<String, OrderedKeyValueStoreAdapter> stores;
public OrderedKeyValueStoreManagerAdapter(OrderedKeyValueStoreManager manager) {
this(manager, new HashMap<String, Integer>());
}
public OrderedKeyValueStoreManagerAdapter(OrderedKeyValueStoreManager manager, Map<String, Integer> keyLengths) {
Preconditions.checkArgument(manager.getFeatures().isKeyOrdered(), "Expected backing store to be ordered: %s", manager);
this.manager = manager;
ImmutableMap.Builder<String, Integer> mb = ImmutableMap.builder();
if (keyLengths != null && !keyLengths.isEmpty()) mb.putAll(keyLengths);
this.keyLengths = mb.build();
this.stores = new HashMap<String, OrderedKeyValueStoreAdapter>();
}
@Override
public StoreFeatures getFeatures() {
return manager.getFeatures();
}
@Override
public StoreTransaction beginTransaction(final BaseTransactionConfig config) throws BackendException {
return manager.beginTransaction(config);
}
@Override
public void close() throws BackendException {
manager.close();
}
@Override
public void clearStorage() throws BackendException {
manager.clearStorage();
}
@Override
public synchronized OrderedKeyValueStoreAdapter openDatabase(String name) throws BackendException {
return openDatabase(name, StoreMetaData.EMPTY);
}
@Override
public synchronized OrderedKeyValueStoreAdapter openDatabase(String name, StoreMetaData.Container metaData)
throws BackendException {
if (!stores.containsKey(name) || stores.get(name).isClosed()) {
OrderedKeyValueStoreAdapter store = wrapKeyValueStore(manager.openDatabase(name), keyLengths);
stores.put(name, store);
}
return stores.get(name);
}
@Override
public void mutateMany(Map<String, Map<StaticBuffer, KCVMutation>> mutations, StoreTransaction txh) throws BackendException {
Map<String, KVMutation> converted = new HashMap<String, KVMutation>(mutations.size());
for (Map.Entry<String, Map<StaticBuffer, KCVMutation>> storeEntry : mutations.entrySet()) {
OrderedKeyValueStoreAdapter store = openDatabase(storeEntry.getKey());
Preconditions.checkNotNull(store);
KVMutation mut = new KVMutation();
for (Map.Entry<StaticBuffer, KCVMutation> entry : storeEntry.getValue().entrySet()) {
StaticBuffer key = entry.getKey();
KCVMutation mutation = entry.getValue();
if (mutation.hasAdditions()) {
for (Entry addition : mutation.getAdditions()) {
mut.addition(store.concatenate(key,addition));
}
}
if (mutation.hasDeletions()) {
for (StaticBuffer del : mutation.getDeletions()) {
mut.deletion(store.concatenate(key, del));
}
}
}
converted.put(storeEntry.getKey(), mut);
}
manager.mutateMany(converted, txh);
}
private static final OrderedKeyValueStoreAdapter wrapKeyValueStore(OrderedKeyValueStore store, Map<String, Integer> keyLengths) {
String name = store.getName();
if (keyLengths.containsKey(name)) {
int keyLength = keyLengths.get(name);
Preconditions.checkArgument(keyLength > 0);
return new OrderedKeyValueStoreAdapter(store, keyLength);
} else {
return new OrderedKeyValueStoreAdapter(store);
}
}
@Override
public List<KeyRange> getLocalKeyPartition() throws BackendException {
return manager.getLocalKeyPartition();
}
@Override
public String getName() {
return manager.getName();
}
}