RandomWordSource.java

/**
 * Copyright 2013-2015 Pierre Merienne
 *
 * 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 stormy.pythian.sandbox;

import static org.apache.commons.lang.RandomStringUtils.randomAlphabetic;
import static stormy.pythian.model.annotation.ComponentType.STREAM_SOURCE;
import static stormy.pythian.model.instance.FeatureType.TEXT;
import storm.trident.Stream;
import storm.trident.TridentTopology;
import storm.trident.testing.FixedBatchSpout;
import stormy.pythian.model.annotation.Documentation;
import stormy.pythian.model.annotation.ExpectedFeature;
import stormy.pythian.model.annotation.NameMapper;
import stormy.pythian.model.annotation.OutputStream;
import stormy.pythian.model.annotation.Topology;
import stormy.pythian.model.component.Component;
import stormy.pythian.model.instance.Instance;
import stormy.pythian.model.instance.NamedFeaturesMapper;
import stormy.pythian.model.instance.TextFeature;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Values;

@Documentation(name = "Random Word Source", description = "Emit random string", type = STREAM_SOURCE)
public class RandomWordSource implements Component {

    private static final long serialVersionUID = 3239910438778205769L;

    public static final String WORD_FEATURE = "word";

    @OutputStream(name = "out")
    private Stream out;

    @NameMapper(stream = "out", expectedFeatures = { @ExpectedFeature(name = WORD_FEATURE, type = TEXT) })
    private NamedFeaturesMapper mapper;

    @Topology
    private TridentTopology topology;

    @Override
    @SuppressWarnings("unchecked")
    public void init() {
        FixedBatchSpout spout = new FixedBatchSpout(new Fields(Instance.NEW_INSTANCE_FIELD), 3, //
                createValues("jackson"), //
                createValues("nathan"), //
                createValues("pierre"), //
                createValues("nathan"), //
                createValues("pierre"), //
                createValues("jackson"), //
                createValues("nathan"), //
                createValues("julie"));

        out = topology.newStream(randomAlphabetic(6), spout);
    }

    private Values createValues(String word) {
        Instance instance = Instance.create(mapper);
        instance.setFeature(WORD_FEATURE, new TextFeature(word));
        return new Values(instance);
    }

}