/**
* 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 storm.trident.operation.builtin;
import backtype.storm.tuple.Values;
import java.util.ArrayList;
import java.util.List;
import storm.trident.operation.TridentCollector;
import storm.trident.state.BaseQueryFunction;
import storm.trident.state.snapshot.ReadOnlySnapshottable;
import storm.trident.tuple.TridentTuple;
public class SnapshotGet extends BaseQueryFunction<ReadOnlySnapshottable, Object> {
@Override
public List<Object> batchRetrieve(ReadOnlySnapshottable state, List<TridentTuple> args) {
List<Object> ret = new ArrayList<Object>(args.size());
Object snapshot = state.get();
for (TridentTuple arg : args) {
ret.add(snapshot);
}
return ret;
}
@Override
public void execute(TridentTuple tuple, Object result, TridentCollector collector) {
collector.emit(new Values(result));
}
}