/*
* 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.cmdline.postag;
import java.io.File;
import java.io.IOException;
import opennlp.tools.cmdline.AbstractTrainerTool;
import opennlp.tools.cmdline.CmdLineUtil;
import opennlp.tools.cmdline.TerminateToolException;
import opennlp.tools.cmdline.params.TrainingToolParams;
import opennlp.tools.cmdline.postag.POSTaggerTrainerTool.TrainerToolParams;
import opennlp.tools.dictionary.Dictionary;
import opennlp.tools.ml.TrainerFactory;
import opennlp.tools.postag.MutableTagDictionary;
import opennlp.tools.postag.POSModel;
import opennlp.tools.postag.POSSample;
import opennlp.tools.postag.POSTaggerFactory;
import opennlp.tools.postag.POSTaggerME;
import opennlp.tools.postag.TagDictionary;
import opennlp.tools.util.InvalidFormatException;
import opennlp.tools.util.TrainingParameters;
import opennlp.tools.util.model.ModelType;
import opennlp.tools.util.model.ModelUtil;
public final class POSTaggerTrainerTool
extends AbstractTrainerTool<POSSample, TrainerToolParams> {
interface TrainerToolParams extends TrainingParams, TrainingToolParams {
}
public POSTaggerTrainerTool() {
super(POSSample.class, TrainerToolParams.class);
}
public String getShortDescription() {
return "trains a model for the part-of-speech tagger";
}
public void run(String format, String[] args) {
super.run(format, args);
mlParams = CmdLineUtil.loadTrainingParameters(params.getParams(), true);
if (mlParams != null && !TrainerFactory.isValid(mlParams.getSettings())) {
throw new TerminateToolException(1, "Training parameters file '" + params.getParams() +
"' is invalid!");
}
if(mlParams == null) {
mlParams = ModelUtil.createDefaultTrainingParameters();
mlParams.put(TrainingParameters.ALGORITHM_PARAM, getModelType(params.getType()).toString());
}
File modelOutFile = params.getModel();
CmdLineUtil.checkOutputFile("pos tagger model", modelOutFile);
Dictionary ngramDict = null;
Integer ngramCutoff = params.getNgram();
if (ngramCutoff != null) {
System.err.print("Building ngram dictionary ... ");
try {
ngramDict = POSTaggerME.buildNGramDictionary(sampleStream, ngramCutoff);
sampleStream.reset();
} catch (IOException e) {
throw new TerminateToolException(-1,
"IO error while building NGram Dictionary: " + e.getMessage(), e);
}
System.err.println("done");
}
POSTaggerFactory postaggerFactory = null;
try {
postaggerFactory = POSTaggerFactory.create(params.getFactory(), ngramDict, null);
} catch (InvalidFormatException e) {
throw new TerminateToolException(-1, e.getMessage(), e);
}
if (params.getDict() != null) {
try {
postaggerFactory.setTagDictionary(postaggerFactory
.createTagDictionary(params.getDict()));
} catch (IOException e) {
throw new TerminateToolException(-1,
"IO error while loading POS Dictionary: " + e.getMessage(), e);
}
}
if (params.getTagDictCutoff() != null) {
try {
TagDictionary dict = postaggerFactory.getTagDictionary();
if (dict == null) {
dict = postaggerFactory.createEmptyTagDictionary();
postaggerFactory.setTagDictionary(dict);
}
if (dict instanceof MutableTagDictionary) {
POSTaggerME.populatePOSDictionary(sampleStream, (MutableTagDictionary)dict,
params.getTagDictCutoff());
} else {
throw new IllegalArgumentException(
"Can't extend a POSDictionary that does not implement MutableTagDictionary.");
}
sampleStream.reset();
} catch (IOException e) {
throw new TerminateToolException(-1,
"IO error while creating/extending POS Dictionary: "
+ e.getMessage(), e);
}
}
POSModel model;
try {
model = opennlp.tools.postag.POSTaggerME.train(params.getLang(),
sampleStream, mlParams, postaggerFactory);
}
catch (IOException e) {
throw new TerminateToolException(-1, "IO error while reading training data or indexing data: "
+ e.getMessage(), e);
}
finally {
try {
sampleStream.close();
} catch (IOException e) {
// sorry that this can fail
}
}
CmdLineUtil.writeModel("pos tagger", modelOutFile, model);
}
static ModelType getModelType(String modelString) {
ModelType model;
if (modelString == null)
modelString = "maxent";
if (modelString.equals("maxent")) {
model = ModelType.MAXENT;
}
else if (modelString.equals("perceptron")) {
model = ModelType.PERCEPTRON;
}
else if (modelString.equals("perceptron_sequence")) {
model = ModelType.PERCEPTRON_SEQUENCE;
}
else {
model = null;
}
return model;
}
}