package de.lmu.ifi.dbs.elki.datasource.filter;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2011
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
import java.util.ArrayList;
import java.util.regex.Pattern;
import de.lmu.ifi.dbs.elki.data.LabelList;
import de.lmu.ifi.dbs.elki.data.type.TypeUtil;
import de.lmu.ifi.dbs.elki.datasource.bundle.MultipleObjectsBundle;
import de.lmu.ifi.dbs.elki.logging.Logging;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.Flag;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.PatternParameter;
/**
* A filter to sort the data set by some label.
*
* @author Erich Schubert
*
* @apiviz.uses LabelList oneway - - «reads»
*/
public class FilterByLabelFilter implements ObjectFilter {
/**
* Class logger
*/
private static final Logging logger = Logging.getLogger(FilterByLabelFilter.class);
/**
* The filter pattern
*/
private final Pattern pattern;
/**
* Inversion flag
*/
private final boolean inverted;
/**
* Constructor.
*
* @param pattern Filter pattern
* @param inverted Inversion flag
*/
public FilterByLabelFilter(Pattern pattern, boolean inverted) {
super();
this.pattern = pattern;
this.inverted = inverted;
}
@Override
public MultipleObjectsBundle filter(final MultipleObjectsBundle objects) {
if(logger.isDebugging()) {
logger.debug("Filtering the data set");
}
// Identify a label column
final int lblcol;
{
int lblc = -1;
for(int i = 0; i < objects.metaLength(); i++) {
if(TypeUtil.GUESSED_LABEL.isAssignableFromType(objects.meta(i))) {
lblc = i;
break;
}
}
lblcol = lblc; // make static
}
MultipleObjectsBundle bundle = new MultipleObjectsBundle();
for(int j = 0; j < objects.metaLength(); j++) {
bundle.appendColumn(objects.meta(j), new ArrayList<Object>());
}
for(int i = 0; i < objects.dataLength(); i++) {
Object l = objects.data(i, lblcol);
if(l instanceof LabelList) {
boolean good = false;
for(String label : (LabelList) l) {
if(pattern.matcher(label).matches()) {
good = true;
break;
}
}
if(good == inverted) {
continue;
}
}
else {
if(!pattern.matcher(l.toString()).matches()) {
continue;
}
}
bundle.appendSimple(objects.getRow(i));
}
return bundle;
}
/**
* Parameterization class.
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
public static class Parameterizer extends AbstractParameterizer {
/**
* Parameter that specifies the filter pattern (regular expression).
* <p>
* Key: {@code -patternfilter.pattern}
* </p>
*/
public static final OptionID LABELFILTER_PATTERN_ID = OptionID.getOrCreateOptionID("patternfilter.pattern", "The filter pattern to use.");
/**
* Flag to use the pattern in inverted mode
* <p>
* Key: {@code -patternfilter.invert}
* </p>
*/
public static final OptionID LABELFILTER_PATTERN_INVERT_ID = OptionID.getOrCreateOptionID("patternfilter.invert", "Flag to invert pattern.");
/**
* The pattern configured.
*/
Pattern pattern = null;
/**
* Inversion flag
*/
private boolean inverted = false;
@Override
protected void makeOptions(Parameterization config) {
super.makeOptions(config);
final PatternParameter patternP = new PatternParameter(LABELFILTER_PATTERN_ID);
if(config.grab(patternP)) {
pattern = patternP.getValue();
}
final Flag invertedF = new Flag(LABELFILTER_PATTERN_INVERT_ID);
if(config.grab(invertedF)) {
inverted = invertedF.getValue();
}
}
@Override
protected Object makeInstance() {
return new FilterByLabelFilter(pattern, inverted);
}
}
}