jstorm-core/src/main/java/backtype/storm/topology/OutputFieldsGetter.java

/**
 * 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 backtype.storm.topology;

import backtype.storm.generated.StreamInfo;
import backtype.storm.tuple.Fields;
import backtype.storm.utils.Utils;
import java.util.HashMap;
import java.util.Map;

public class OutputFieldsGetter implements OutputFieldsDeclarer {
    private Map<String, StreamInfo> _fields = new HashMap<String, StreamInfo>();

    public void declare(Fields fields) {
        declare(false, fields);
    }

    public void declare(boolean direct, Fields fields) {
        declareStream(Utils.DEFAULT_STREAM_ID, direct, fields);
    }

    public void declareStream(String streamId, Fields fields) {
        declareStream(streamId, false, fields);
    }

    public void declareStream(String streamId, boolean direct, Fields fields) {
        if (_fields.containsKey(streamId)) {
            throw new IllegalArgumentException("Fields for " + streamId + " already set");
        }
        _fields.put(streamId, new StreamInfo(fields.toList(), direct));
    }

    public Map<String, StreamInfo> getFieldsDeclaration() {
        return _fields;
    }

}