Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||||||
CountFunction |
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| 3.0;3 |
1 | /* |
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2 | * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/function/CountFunction.java,v 1.13 2005/06/28 13:44:45 elharo Exp $ |
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3 | * $Revision: 1.13 $ |
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4 | * $Date: 2005/06/28 13:44:45 $ |
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5 | * |
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6 | * ==================================================================== |
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7 | * |
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8 | * Copyright (C) 2000-2002 bob mcwhirter & James Strachan. |
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9 | * All rights reserved. |
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10 | * |
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11 | * Redistribution and use in source and binary forms, with or without |
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12 | * modification, are permitted provided that the following conditions |
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13 | * are met: |
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14 | * |
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15 | * 1. Redistributions of source code must retain the above copyright |
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16 | * notice, this list of conditions, and the following disclaimer. |
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17 | * |
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18 | * 2. Redistributions in binary form must reproduce the above copyright |
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19 | * notice, this list of conditions, and the disclaimer that follows |
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20 | * these conditions in the documentation and/or other materials |
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21 | * provided with the distribution. |
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22 | * |
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23 | * 3. The name "Jaxen" must not be used to endorse or promote products |
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24 | * derived from this software without prior written permission. For |
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25 | * written permission, please contact license@jaxen.org. |
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26 | * |
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27 | * 4. Products derived from this software may not be called "Jaxen", nor |
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28 | * may "Jaxen" appear in their name, without prior written permission |
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29 | * from the Jaxen Project Management (pm@jaxen.org). |
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30 | * |
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31 | * In addition, we request (but do not require) that you include in the |
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32 | * end-user documentation provided with the redistribution and/or in the |
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33 | * software itself an acknowledgement equivalent to the following: |
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34 | * "This product includes software developed by the |
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35 | * Jaxen Project <http://www.jaxen.org/>." |
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36 | * Alternatively, the acknowledgment may be graphical using the logos |
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37 | * available at http://www.jaxen.org/ |
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38 | * |
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39 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
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40 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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41 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
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42 | * DISCLAIMED. IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT |
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43 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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44 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
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45 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
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46 | * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
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47 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
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48 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
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49 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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50 | * SUCH DAMAGE. |
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51 | * |
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52 | * ==================================================================== |
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53 | * This software consists of voluntary contributions made by many |
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54 | * individuals on behalf of the Jaxen Project and was originally |
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55 | * created by bob mcwhirter <bob@werken.com> and |
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56 | * James Strachan <jstrachan@apache.org>. For more information on the |
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57 | * Jaxen Project, please see <http://www.jaxen.org/>. |
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58 | * |
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59 | * $Id: CountFunction.java,v 1.13 2005/06/28 13:44:45 elharo Exp $ |
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60 | */ |
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61 | ||
62 | package org.jaxen.function; |
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63 | ||
64 | import java.util.List; |
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65 | ||
66 | import org.jaxen.Context; |
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67 | import org.jaxen.Function; |
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68 | import org.jaxen.FunctionCallException; |
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69 | ||
70 | /** |
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71 | * <p><b>4.1</b> <code><i>number</i> count(<i>node-set</i>)</code></p> |
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72 | * |
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73 | * <blockquote src="http://www.w3.org/TR/xpath#function-count"> |
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74 | * The <b>count</b> function returns the number of nodes in the argument node-set. |
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75 | * </blockquote> |
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76 | * @author bob mcwhirter (bob @ werken.com) |
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77 | * @see <a href="http://www.w3.org/TR/xpath#function-count">Section 4.1 of the XPath Specification</a> |
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78 | */ |
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79 | public class CountFunction implements Function |
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80 | { |
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81 | ||
82 | /** |
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83 | * Create a new <code>CountFunction</code> object. |
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84 | */ |
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85 | 294 | public CountFunction() {} |
86 | ||
87 | /** |
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88 | * <p> |
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89 | * Returns the number of nodes in the specified node-set. |
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90 | * </p> |
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91 | * @param context ignored |
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92 | * @param args the function arguments |
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93 | * |
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94 | * @return a <code>Double</code> giving the integral number of items in the first argument |
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95 | * |
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96 | * @throws FunctionCallException if args does not have exactly one |
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97 | * item; or that item is not a <code>List</code> |
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98 | */ |
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99 | public Object call(Context context, |
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100 | List args) throws FunctionCallException |
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101 | { |
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102 | 1608 | if (args.size() == 1) |
103 | { |
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104 | 1596 | return evaluate( args.get(0) ); |
105 | } |
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106 | ||
107 | 12 | throw new FunctionCallException( "count() requires one argument." ); |
108 | } |
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109 | ||
110 | /** |
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111 | * <p> |
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112 | * Returns the number of nodes in the specified node-set. |
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113 | * </p> |
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114 | * |
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115 | * @param obj a <code>List</code> of nodes |
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116 | * @return the integral number of items in the list |
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117 | * @throws FunctionCallException if obj is not a <code>List</code> |
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118 | */ |
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119 | public static Double evaluate(Object obj) throws FunctionCallException |
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120 | { |
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121 | ||
122 | 1596 | if (obj instanceof List) |
123 | { |
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124 | 1590 | return new Double( ((List) obj).size() ); |
125 | } |
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126 | ||
127 | 6 | throw new FunctionCallException("count() function can only be used for node-sets"); |
128 | ||
129 | } |
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130 | ||
131 | } |