/*
* 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.coref;
import java.io.IOException;
import opennlp.tools.coref.mention.MentionContext;
import opennlp.tools.coref.mention.PTBHeadFinder;
import opennlp.tools.coref.mention.ShallowParseMentionFinder;
import opennlp.tools.coref.resolver.AbstractResolver;
import opennlp.tools.coref.resolver.CommonNounResolver;
import opennlp.tools.coref.resolver.DefiniteNounResolver;
import opennlp.tools.coref.resolver.FixedNonReferentialResolver;
import opennlp.tools.coref.resolver.IsAResolver;
import opennlp.tools.coref.resolver.MaxentResolver;
import opennlp.tools.coref.resolver.NonReferentialResolver;
import opennlp.tools.coref.resolver.PerfectResolver;
import opennlp.tools.coref.resolver.PluralNounResolver;
import opennlp.tools.coref.resolver.PluralPronounResolver;
import opennlp.tools.coref.resolver.ProperNounResolver;
import opennlp.tools.coref.resolver.ResolverMode;
import opennlp.tools.coref.resolver.SingularPronounResolver;
import opennlp.tools.coref.resolver.SpeechPronounResolver;
import opennlp.tools.coref.sim.Gender;
import opennlp.tools.coref.sim.MaxentCompatibilityModel;
import opennlp.tools.coref.sim.Number;
import opennlp.tools.coref.sim.SimilarityModel;
/**
* This class perform coreference for treebank style parses or for noun-phrase chunked data.
* Non-constituent entities such as pre-nominal named-entities and sub entities in simple coordinated
* noun phases will be created. This linker requires that named-entity information also be provided.
* This information can be added to the parse using the -parse option with EnglishNameFinder.
*/
public class DefaultLinker extends AbstractLinker {
protected MaxentCompatibilityModel mcm;
/**
* Creates a new linker with the specified model directory, running in the specified mode.
* @param modelDirectory The directory where the models for this linker are kept.
* @param mode The mode that this linker is running in.
* @throws IOException when the models can not be read or written to based on the mode.
*/
public DefaultLinker(String modelDirectory, LinkerMode mode) throws IOException {
this(modelDirectory,mode,true,-1);
}
/**
* Creates a new linker with the specified model directory, running in the specified mode which uses a discourse model
* based on the specified parameter.
* @param modelDirectory The directory where the models for this linker are kept.
* @param mode The mode that this linker is running in.
* @param useDiscourseModel Whether the model should use a discourse model or not.
* @throws IOException when the models can not be read or written to based on the mode.
*/
public DefaultLinker(String modelDirectory, LinkerMode mode, boolean useDiscourseModel) throws IOException {
this(modelDirectory,mode,useDiscourseModel,-1);
}
/**
* Creates a new linker with the specified model directory, running in the specified mode which uses a discourse model
* based on the specified parameter and uses the specified fixed non-referential probability.
* @param modelDirectory The directory where the models for this linker are kept.
* @param mode The mode that this linker is running in.
* @param useDiscourseModel Whether the model should use a discourse model or not.
* @param fixedNonReferentialProbability The probability which resolvers are required to exceed to positi a coreference relationship.
* @throws IOException when the models can not be read or written to based on the mode.
*/
public DefaultLinker(String modelDirectory, LinkerMode mode, boolean useDiscourseModel, double fixedNonReferentialProbability) throws IOException {
super(modelDirectory, mode, useDiscourseModel);
if (mode != LinkerMode.SIM) {
mcm = new MaxentCompatibilityModel(corefProject);
}
initHeadFinder();
initMentionFinder();
if (mode != LinkerMode.SIM) {
initResolvers(mode, fixedNonReferentialProbability);
entities = new DiscourseEntity[resolvers.length];
}
}
/**
* Initializes the resolvers used by this linker.
* @param mode The mode in which this linker is being used.
* @param fixedNonReferentialProbability
* @throws IOException
*/
protected void initResolvers(LinkerMode mode, double fixedNonReferentialProbability) throws IOException {
if (mode == LinkerMode.TRAIN) {
mentionFinder.setPrenominalNamedEntityCollection(false);
mentionFinder.setCoordinatedNounPhraseCollection(false);
}
SINGULAR_PRONOUN = 0;
if (LinkerMode.TEST == mode || LinkerMode.EVAL == mode) {
if (fixedNonReferentialProbability < 0) {
resolvers = new MaxentResolver[] {
new SingularPronounResolver(corefProject, ResolverMode.TEST),
new ProperNounResolver(corefProject, ResolverMode.TEST),
new DefiniteNounResolver(corefProject, ResolverMode.TEST),
new IsAResolver(corefProject, ResolverMode.TEST),
new PluralPronounResolver(corefProject, ResolverMode.TEST),
new PluralNounResolver(corefProject, ResolverMode.TEST),
new CommonNounResolver(corefProject, ResolverMode.TEST),
new SpeechPronounResolver(corefProject, ResolverMode.TEST)
};
}
else {
NonReferentialResolver nrr = new FixedNonReferentialResolver(fixedNonReferentialProbability);
resolvers = new MaxentResolver[] {
new SingularPronounResolver(corefProject, ResolverMode.TEST,nrr),
new ProperNounResolver(corefProject, ResolverMode.TEST,nrr),
new DefiniteNounResolver(corefProject, ResolverMode.TEST,nrr),
new IsAResolver(corefProject, ResolverMode.TEST,nrr),
new PluralPronounResolver(corefProject, ResolverMode.TEST,nrr),
new PluralNounResolver(corefProject, ResolverMode.TEST,nrr),
new CommonNounResolver(corefProject, ResolverMode.TEST,nrr),
new SpeechPronounResolver(corefProject, ResolverMode.TEST,nrr)
};
}
if (LinkerMode.EVAL == mode) {
//String[] names = {"Pronoun", "Proper", "Def-NP", "Is-a", "Plural Pronoun"};
//eval = new Evaluation(names);
}
MaxentResolver.setSimilarityModel(SimilarityModel.testModel(corefProject + "/sim"));
}
else if (LinkerMode.TRAIN == mode) {
resolvers = new AbstractResolver[9];
resolvers[0] = new SingularPronounResolver(corefProject, ResolverMode.TRAIN);
resolvers[1] = new ProperNounResolver(corefProject, ResolverMode.TRAIN);
resolvers[2] = new DefiniteNounResolver(corefProject, ResolverMode.TRAIN);
resolvers[3] = new IsAResolver(corefProject, ResolverMode.TRAIN);
resolvers[4] = new PluralPronounResolver(corefProject, ResolverMode.TRAIN);
resolvers[5] = new PluralNounResolver(corefProject, ResolverMode.TRAIN);
resolvers[6] = new CommonNounResolver(corefProject, ResolverMode.TRAIN);
resolvers[7] = new SpeechPronounResolver(corefProject, ResolverMode.TRAIN);
resolvers[8] = new PerfectResolver();
}
else {
System.err.println("DefaultLinker: Invalid Mode");
}
}
/**
* Initializes the head finder for this linker.
*/
protected void initHeadFinder() {
headFinder = PTBHeadFinder.getInstance();
}
/**
* Initializes the mention finder for this linker.
* This can be over-ridden to change the space of mentions used for coreference.
*/
protected void initMentionFinder() {
mentionFinder = ShallowParseMentionFinder.getInstance(headFinder);
}
@Override
protected Gender computeGender(MentionContext mention) {
return mcm.computeGender(mention);
}
@Override
protected Number computeNumber(MentionContext mention) {
return mcm.computeNumber(mention);
}
}