/*
* 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.namefind;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import opennlp.model.AbstractModel;
import opennlp.model.Event;
import opennlp.model.Sequence;
import opennlp.model.SequenceStream;
import opennlp.tools.util.ObjectStream;
import opennlp.tools.util.featuregen.AdaptiveFeatureGenerator;
public class NameSampleSequenceStream implements SequenceStream {
private NameContextGenerator pcg;
private List<NameSample> samples;
public NameSampleSequenceStream(ObjectStream<NameSample> psi) throws IOException {
this(psi, new DefaultNameContextGenerator((AdaptiveFeatureGenerator) null));
}
public NameSampleSequenceStream(ObjectStream<NameSample> psi, AdaptiveFeatureGenerator featureGen)
throws IOException {
this(psi, new DefaultNameContextGenerator(featureGen));
}
public NameSampleSequenceStream(ObjectStream<NameSample> psi, NameContextGenerator pcg)
throws IOException {
samples = new ArrayList<NameSample>();
NameSample sample;
while((sample = psi.read()) != null) {
samples.add(sample);
}
System.err.println("Got "+samples.size()+" sequences");
this.pcg = pcg;
}
@SuppressWarnings("unchecked")
public Event[] updateContext(Sequence sequence, AbstractModel model) {
Sequence<NameSample> pss = sequence;
TokenNameFinder tagger = new NameFinderME(new TokenNameFinderModel("x-unspecified", model, Collections.<String, Object>emptyMap(), null));
String[] sentence = pss.getSource().getSentence();
String[] tags = NameFinderEventStream.generateOutcomes(tagger.find(sentence), null, sentence.length);
Event[] events = new Event[sentence.length];
NameFinderEventStream.generateEvents(sentence,tags,pcg).toArray(events);
return events;
}
@SuppressWarnings("unchecked")
public Iterator<Sequence> iterator() {
return new NameSampleSequenceIterator(samples.iterator());
}
}
class NameSampleSequenceIterator implements Iterator<Sequence> {
private Iterator<NameSample> psi;
private NameContextGenerator cg;
public NameSampleSequenceIterator(Iterator<NameSample> psi) {
this.psi = psi;
cg = new DefaultNameContextGenerator(null);
}
public boolean hasNext() {
return psi.hasNext();
}
public Sequence<NameSample> next() {
NameSample sample = psi.next();
String sentence[] = sample.getSentence();
String tags[] = NameFinderEventStream.generateOutcomes(sample.getNames(), null, sentence.length);
Event[] events = new Event[sentence.length];
for (int i=0; i < sentence.length; i++) {
// it is safe to pass the tags as previous tags because
// the context generator does not look for non predicted tags
String[] context = cg.getContext(i, sentence, tags, null);
events[i] = new Event(tags[i], context);
}
Sequence<NameSample> sequence = new Sequence<NameSample>(events,sample);
return sequence;
}
public void remove() {
throw new UnsupportedOperationException();
}
}