/*
* 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 opennlp.tools.util;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.fail;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import opennlp.tools.ml.model.Event;
import org.junit.Test;
/**
* Tests for the {@link AbstractEventStream} class.
*/
public class AbstractEventStreamTest {
private enum RESULT {
EVENTS,
EMPTY
};
/**
* This class extends the {@link AbstractEventStream} to help
* testing the {@link AbstractEventStream#hasNext()}
* and {@link AbstractEventStream#next()} methods.
*/
class TestEventStream extends AbstractEventStream<RESULT> {
public TestEventStream(ObjectStream<RESULT> samples) {
super(samples);
}
/**
* Creates {@link Iterator}s for testing.
*
* @param sample parameter to specify the output
*
* @return it returns an {@link Iterator} which contains one
* {@link Event} object if the sample parameter equals
* {@link RESULT#EVENTS} or an empty {@link Iterator} if the sample
* parameter equals {@link RESULT#EMPTY}.
*/
@Override
protected Iterator<Event> createEvents(RESULT sample) {
if (RESULT.EVENTS.equals(sample)) {
List<Event> events = new ArrayList<Event>();
events.add(new Event("test", new String[]{"f1", "f2"}));
return events.iterator();
}
else if (RESULT.EMPTY.equals(sample)) {
List<Event> emptyList = Collections.emptyList();
return emptyList.iterator();
}
else {
// throws runtime exception, execution stops here
fail();
return null;
}
}
}
/**
* Checks if the {@link AbstractEventStream} behavior is correctly
* if the {@link AbstractEventStream#createEvents(Object)} method
* return iterators with events and empty iterators.
*/
@Test
public void testStandardCase() throws IOException {
List<RESULT> samples = new ArrayList<RESULT>();
samples.add(RESULT.EVENTS);
samples.add(RESULT.EMPTY);
samples.add(RESULT.EVENTS);
TestEventStream eventStream = new TestEventStream(new CollectionObjectStream<RESULT>(samples));
int eventCounter = 0;
while (eventStream.read() != null) {
eventCounter++;
}
assertEquals(2, eventCounter);
}
/**
* Checks if the {@link AbstractEventStream} behavior is correctly
* if the {@link AbstractEventStream#createEvents(Object)} method
* only returns empty iterators.
*/
@Test
public void testEmtpyEventStream() throws IOException {
List<RESULT> samples = new ArrayList<RESULT>();
samples.add(RESULT.EMPTY);
TestEventStream eventStream = new TestEventStream(new CollectionObjectStream<RESULT>(samples));
assertNull(eventStream.read());
// now check if it can handle multiple empty event iterators
samples.add(RESULT.EMPTY);
samples.add(RESULT.EMPTY);
eventStream = new TestEventStream(new CollectionObjectStream<RESULT>(samples));
assertNull(eventStream.read());
}
}