StreamWords.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 org.apache.ignite.examples.streaming.wordcount;

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.LineNumberReader;
import org.apache.ignite.Ignite;
import org.apache.ignite.IgniteCache;
import org.apache.ignite.IgniteDataStreamer;
import org.apache.ignite.Ignition;
import org.apache.ignite.cache.affinity.AffinityUuid;
import org.apache.ignite.examples.ExampleNodeStartup;
import org.apache.ignite.examples.ExamplesUtils;

/**
 * Stream words into Ignite cache.
 * To start the example, you should:
 * <ul>
 *     <li>Start a few nodes using {@link ExampleNodeStartup}.</li>
 *     <li>Start streaming using {@link StreamWords}.</li>
 *     <li>Start querying popular words using {@link QueryWords}.</li>
 * </ul>
 */
public class StreamWords {
    /**
     * Starts words streaming.
     *
     * @param args Command line arguments (none required).
     * @throws Exception If failed.
     */
    public static void main(String[] args) throws Exception {
        // Mark this cluster member as client.
        Ignition.setClientMode(true);

        try (Ignite ignite = Ignition.start("examples/config/example-ignite.xml")) {
            if (!ExamplesUtils.hasServerNodes(ignite))
                return;

            // The cache is configured with sliding window holding 1 second of the streaming data.
            IgniteCache<AffinityUuid, String> stmCache = ignite.getOrCreateCache(CacheConfig.wordCache());

            try (IgniteDataStreamer<AffinityUuid, String> stmr = ignite.dataStreamer(stmCache.getName())) {
                // Stream words from "alice-in-wonderland" book.
                while (true) {
                    InputStream in = StreamWords.class.getResourceAsStream("alice-in-wonderland.txt");

                    try (LineNumberReader rdr = new LineNumberReader(new InputStreamReader(in))) {
                        for (String line = rdr.readLine(); line != null; line = rdr.readLine()) {
                            for (String word : line.split(" "))
                                if (!word.isEmpty())
                                    // Stream words into Ignite.
                                    // By using AffinityUuid we ensure that identical
                                    // words are processed on the same cluster node.
                                    stmr.addData(new AffinityUuid(word), word);
                        }
                    }
                }
            }
        }
    }
}