/*
* Copyright 2014
* Ubiquitous Knowledge Processing (UKP) Lab
* Technische Universität Darmstadt
*
* Licensed 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 de.tudarmstadt.ukp.dkpro.core.textnormalizer.annotations;
import static org.apache.uima.fit.util.JCasUtil.select;
import java.util.LinkedList;
import java.util.List;
import java.util.regex.Pattern;
import org.apache.uima.UimaContext;
import org.apache.uima.analysis_engine.AnalysisEngineProcessException;
import org.apache.uima.fit.component.JCasAnnotator_ImplBase;
import org.apache.uima.fit.descriptor.ConfigurationParameter;
import org.apache.uima.jcas.JCas;
import org.apache.uima.resource.ResourceInitializationException;
import de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Token;
/**
* Remove every token that does or does not match a given regular expression.
*
*
*/
public class RegexTokenFilter
extends JCasAnnotator_ImplBase
{
/**
* Every token that does or does not match this regular expression will be removed.
*/
public static final String PARAM_REGEX = "regex";
@ConfigurationParameter(name = PARAM_REGEX, mandatory = true)
private String regex;
/**
* If this parameter is set to true (default), retain only tokens that match the regex given in
* {@link #PARAM_REGEX}. If set to false, all tokens that match the given regex are removed.
*/
public static final String PARAM_MUST_MATCH = "mustMatch";
@ConfigurationParameter(name = PARAM_MUST_MATCH, mandatory = true, defaultValue = "true")
private boolean mustMatch;
private Pattern filterRegex;
@Override
public void initialize(UimaContext context)
throws ResourceInitializationException
{
super.initialize(context);
filterRegex = Pattern.compile(regex);
};
@Override
public void process(JCas aJCas)
throws AnalysisEngineProcessException
{
List<Token> toRemove = new LinkedList<>();
for (Token token : select(aJCas, Token.class)) {
if (mustMatch && !filterRegex.matcher(token.getCoveredText()).matches()
|| !mustMatch && filterRegex.matcher(token.getCoveredText()).matches()) {
toRemove.add(token);
}
}
for (Token token : toRemove) {
token.removeFromIndexes();
}
}
}