// 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;
import org.janusgraph.diskstorage.BackendException;
import org.janusgraph.diskstorage.Entry;
import org.janusgraph.diskstorage.StaticBuffer;
import java.util.List;
/**
* Wraps a {@link KeyColumnValueStore} and throws exceptions when a mutation is attempted.
*
* @author Matthias Bröcheler (me@matthiasb.com);
*/
public class ReadOnlyKeyColumnValueStore extends KCVSProxy {
public ReadOnlyKeyColumnValueStore(KeyColumnValueStore store) {
super(store);
}
@Override
public void acquireLock(StaticBuffer key, StaticBuffer column, StaticBuffer expectedValue,
StoreTransaction txh) throws BackendException {
throw new UnsupportedOperationException("Cannot lock on a read-only store");
}
@Override
public void mutate(StaticBuffer key, List<Entry> additions, List<StaticBuffer> deletions, StoreTransaction txh) throws BackendException {
throw new UnsupportedOperationException("Cannot mutate a read-only store");
}
}