opennlp.tools.chunker.ChunkerEventStream Maven / Gradle / Ivy
/*
* 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.chunker;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import opennlp.tools.ml.model.Event;
import opennlp.tools.util.AbstractEventStream;
import opennlp.tools.util.ObjectStream;
/**
* Class for creating an event stream out of data files for training a {@link Chunker}.
*/
public class ChunkerEventStream extends AbstractEventStream {
private final ChunkerContextGenerator cg;
/**
* Creates a new event stream based on the specified data stream using the given context generator.
*
* @param d The data stream for this event stream.
* @param cg A {@link ChunkerContextGenerator} which should be used for the event stream {@code d}.
*/
public ChunkerEventStream(ObjectStream d, ChunkerContextGenerator cg) {
super(d);
this.cg = cg;
}
@Override
protected Iterator createEvents(ChunkSample sample) {
if (sample != null) {
List events = new ArrayList<>();
String[] toksArray = sample.getSentence();
String[] tagsArray = sample.getTags();
String[] predsArray = sample.getPreds();
for (int ei = 0, el = sample.getSentence().length; ei < el; ei++) {
events.add(new Event(predsArray[ei], cg.getContext(ei,toksArray,tagsArray,predsArray)));
}
return events.iterator();
}
else {
return Collections.emptyListIterator();
}
}
}