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1   /*
2    * ====================================================================
3    * 
4    * The Apache Software License, Version 1.1
5    *
6    * Copyright (c) 2003 Nick Lothian. All rights reserved.
7    *
8    * Redistribution and use in source and binary forms, with or without
9    * modification, are permitted provided that the following conditions
10   * are met:
11   *
12   * 1. Redistributions of source code must retain the above copyright
13   *    notice, this list of conditions and the following disclaimer. 
14   *
15   * 2. Redistributions in binary form must reproduce the above copyright
16   *    notice, this list of conditions and the following disclaimer in
17   *    the documentation and/or other materials provided with the
18   *    distribution.
19   *
20   * 3. The end-user documentation included with the redistribution, if
21   *    any, must include the following acknowlegement:  
22   *       "This product includes software developed by the 
23   *        developers of Classifier4J (http://classifier4j.sf.net/)."
24   *    Alternately, this acknowlegement may appear in the software itself,
25   *    if and wherever such third-party acknowlegements normally appear.
26   *
27   * 4. The name "Classifier4J" must not be used to endorse or promote 
28   *    products derived from this software without prior written 
29   *    permission. For written permission, please contact   
30   *    http://sourceforge.net/users/nicklothian/.
31   *
32   * 5. Products derived from this software may not be called 
33   *    "Classifier4J", nor may "Classifier4J" appear in their names 
34   *    without prior written permission. For written permission, please 
35   *    contact http://sourceforge.net/users/nicklothian/.
36   *
37   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
40   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
41   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
44   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
45   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
46   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
47   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48   * SUCH DAMAGE.
49   * ====================================================================
50   */
51  
52  package net.sf.classifier4J;
53  
54  /***
55   * 
56   * Implementaion of the {@link net.sf.classifier4J.IClassifier#setMatchCutoff(double)} 
57   * and {@link net.sf.classifier4J.IClassifier#isMatch(java.lang.String)} methods.
58   * 
59   * @author Nick Lothian
60   *
61   */
62  public abstract class AbstractClassifier implements IClassifier {
63  
64      protected double cutoff = IClassifier.DEFAULT_CUTOFF;
65  
66      /***
67       * 
68       * <p>This implementation throws an IllegalArgumentException if cutoff is 
69       * greater than 1 or less than 0.</p>
70       * 	 
71       * 
72       * @param cutoff Used to determine the mimimum probability that should be classified as a match  
73       * @throws IllegalArgumentException if if cutoff is greater than 1 or less than 0 
74       * 
75       */
76      public void setMatchCutoff(double cutoff) {
77          if (cutoff > 1 || cutoff < 0) {
78              throw new IllegalArgumentException("Cutoff must be equal or less than 1 and greater than or equal to 0");
79          }
80  
81          this.cutoff = cutoff;
82      }
83  
84      public double getMatchCutoff() {
85          return this.cutoff;
86      }
87  
88      /***
89       * <p>Implementation of {@link net.sf.classifier4J.IClassifier#isMatch(java.lang.String)}
90       * method.</p>
91       * 
92       * @see net.sf.classifier4J.IClassifier#isMatch(java.lang.String)
93       */
94      public boolean isMatch(String input) throws ClassifierException {
95          double matchProbability = classify(input);
96  
97          return isMatch(matchProbability);
98      }
99  
100     /***
101      * @see net.sf.classifier4J.IClassifier#isMatch(double)
102      */
103     public boolean isMatch(double matchProbability) {
104         return (matchProbability >= cutoff);
105     }
106 
107 }