ruta-core/src/main/java/org/apache/uima/ruta/rule/quantifier/StarGreedy.java

/*
 * 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 org.apache.uima.ruta.rule.quantifier;

import java.util.List;

import org.apache.uima.cas.text.AnnotationFS;
import org.apache.uima.ruta.RutaStream;
import org.apache.uima.ruta.rule.ComposedRuleElementMatch;
import org.apache.uima.ruta.rule.MatchContext;
import org.apache.uima.ruta.rule.RuleElementMatch;
import org.apache.uima.ruta.visitor.InferenceCrowd;

public class StarGreedy extends AbstractRuleElementQuantifier {

  public StarGreedy() {
    super();
  }

  @Override
  public List<RuleElementMatch> evaluateMatches(List<RuleElementMatch> matches,
          MatchContext context, RutaStream stream, InferenceCrowd crowd) {
    boolean result = true;
    if (matches == null) {
      return null;
    }
    for (RuleElementMatch match : matches) {
      result &= match.matched() || (!(match instanceof ComposedRuleElementMatch)
              && match.getTextsMatched().isEmpty());
    }
    if (!result && matches.size() > 0) {
      matches.remove(matches.size() - 1);
      updateLabelAssignment(matches, context, stream);
      result = true;
    }
    if (result) {
      return matches;
    } else {
      return null;
    }
  }

  @Override
  public boolean continueMatch(boolean after, MatchContext context, AnnotationFS annotation,
          ComposedRuleElementMatch containerMatch, RutaStream stream, InferenceCrowd crowd) {
    if (annotation == null) {
      // do not try to continue a match that totally failed
      return false;
    }
    return true;
  }

  @Override
  public boolean isOptional(MatchContext context, RutaStream stream) {
    return true;
  }
}