001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2008-2012 SonarSource
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    
021    package org.sonar.squid.recognizer;
022    
023    public abstract class Detector {
024    
025      public final double probability;
026    
027      public Detector(double probability) {
028        if (probability < 0 || probability > 1) {
029          throw new IllegalArgumentException("probability should be between [0 .. 1]");
030        }
031        this.probability = probability;
032      }
033    
034      public abstract int scan(String line);
035    
036      public final double recognition(String line) {
037        int matchers = scan(line);
038        if (matchers == 0) {
039          return 0;
040        }
041        return 1 - Math.pow(1 - probability, scan(line));
042      }
043    }