wayang-commons/wayang-basic/src/test/java/org/apache/wayang/basic/operators/MaterializedGroupByOperatorTest.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.wayang.basic.operators;

import java.util.stream.StreamSupport;
import org.apache.wayang.core.function.TransformationDescriptor;
import org.apache.wayang.core.types.DataSetType;
import org.apache.wayang.core.types.DataUnitType;
import org.junit.Test;

/**
 * Tests for the {@link MaterializedGroupByOperator}.
 */
public class MaterializedGroupByOperatorTest {

    @Test
    public void testConnectingToMap() {
        final MaterializedGroupByOperator<String, Integer> materializedGroupByOperator =
                new MaterializedGroupByOperator<>(String::length, String.class, Integer.class);
        final MapOperator<Iterable<String>, Integer> mapOperator = new MapOperator<>(
                new TransformationDescriptor<>(
                        strings -> (int) StreamSupport.stream(strings.spliterator(), false).count(),
                        DataUnitType.createBasicUnchecked(Iterable.class),
                        DataUnitType.createBasic(Integer.class)
                ),
                DataSetType.createGrouped(String.class),
                DataSetType.createDefault(Integer.class)
        );
        materializedGroupByOperator.connectTo(0, mapOperator, 0);
    }

}