/**
 * 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.impl;

import java.util.Map;
import storm.trident.operation.Filter;
import storm.trident.operation.Function;
import storm.trident.operation.TridentCollector;
import storm.trident.operation.TridentOperationContext;
import storm.trident.tuple.TridentTuple;

// works by emitting null to the collector. since the planner knows this is an ADD node with
// no new output fields, it just passes the tuple forward
public class FilterExecutor implements Function {
    Filter _filter;

    public FilterExecutor(Filter filter) {
        _filter = filter;
    }

    @Override
    public void execute(TridentTuple tuple, TridentCollector collector) {
        if (_filter.isKeep(tuple)) {
            collector.emit(null);
        }
    }

    @Override
    public void prepare(Map conf, TridentOperationContext context) {
        _filter.prepare(conf, context);
    }

    @Override
    public void cleanup() {
        _filter.cleanup();
    }

}