opennlp.tools.ml.model.DataIndexerFactory Maven / Gradle / Ivy
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* 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.ml.model;
import java.util.HashMap;
import java.util.Map;
import opennlp.tools.ml.AbstractEventTrainer;
import opennlp.tools.util.TrainingParameters;
import opennlp.tools.util.ext.ExtensionLoader;
import opennlp.tools.util.ext.ExtensionNotLoadedException;
/**
* A factory that produces {@link DataIndexer} instances.
*
* @see DataIndexer
*/
public class DataIndexerFactory {
/**
* Instantiates a {@link DataIndexer} configured via {@link TrainingParameters}.
*
* @param parameters The {@link TrainingParameters} used for configuration.
* @param reportMap The {@link Map} used for reporting.
* @return A ready to use {@link DataIndexer} instance.
*
* @throws ExtensionNotLoadedException Thrown if a class name was configured for the indexer, yet
* the extension could not be loaded.
* @see ExtensionLoader
*/
public static DataIndexer getDataIndexer(TrainingParameters parameters, Map reportMap) {
// The default is currently a 2-Pass data index. Is this what we really want?
String indexerParam = parameters.getStringParameter(AbstractEventTrainer.DATA_INDEXER_PARAM,
AbstractEventTrainer.DATA_INDEXER_TWO_PASS_VALUE);
// allow the user to pass in a report map. If the don't, create one.
if (reportMap == null) {
reportMap = new HashMap<>();
}
DataIndexer indexer;
switch (indexerParam) {
case AbstractEventTrainer.DATA_INDEXER_ONE_PASS_VALUE:
indexer = new OnePassDataIndexer();
break;
case AbstractEventTrainer.DATA_INDEXER_TWO_PASS_VALUE:
indexer = new TwoPassDataIndexer();
break;
case AbstractEventTrainer.DATA_INDEXER_ONE_PASS_REAL_VALUE:
indexer = new OnePassRealValueDataIndexer();
break;
default:
// if the user passes in a class name for the indexer, try to instantiate the class.
indexer = ExtensionLoader.instantiateExtension(DataIndexer.class, indexerParam);
}
indexer.init(parameters, reportMap);
return indexer;
}
}