flink-tests/src/test/java/org/apache/flink/test/example/java/WordCountWithCollectionITCase.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.flink.test.example.java;

import org.apache.flink.api.java.DataSet;
import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.api.java.aggregation.Aggregations;
import org.apache.flink.api.java.io.LocalCollectionOutputFormat;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.examples.java.wordcount.WordCount;
import org.apache.flink.test.testdata.WordCountData;
import org.apache.flink.test.util.JavaProgramTestBase;

import org.junit.Assert;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/** WordCount with collection example. */
public class WordCountWithCollectionITCase extends JavaProgramTestBase {

    private final List<Tuple2<String, Integer>> resultsCollected =
            new ArrayList<Tuple2<String, Integer>>();

    @Override
    protected void postSubmit() throws Exception {
        String[] result = new String[resultsCollected.size()];
        for (int i = 0; i < result.length; i++) {
            result[i] = resultsCollected.get(i).toString();
        }
        Arrays.sort(result);

        String[] expected = WordCountData.COUNTS_AS_TUPLES.split("\n");
        Arrays.sort(expected);

        Assert.assertEquals(
                "Different number of lines in expected and obtained result.",
                expected.length,
                result.length);
        Assert.assertArrayEquals(expected, result);
    }

    @Override
    protected void testProgram() throws Exception {
        final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

        DataSet<String> text = env.fromElements(WordCountData.TEXT);
        DataSet<Tuple2<String, Integer>> words = text.flatMap(new WordCount.Tokenizer());
        DataSet<Tuple2<String, Integer>> result = words.groupBy(0).aggregate(Aggregations.SUM, 1);

        result.output(new LocalCollectionOutputFormat<Tuple2<String, Integer>>(resultsCollected));
        env.execute("Word Count Collection");
    }
}