SubstringAfterFunction


1   /*
2    * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/function/SubstringAfterFunction.java,v 1.8 2005/06/26 16:07:23 elharo Exp $
3    * $Revision: 1.8 $
4    * $Date: 2005/06/26 16:07:23 $
5    *
6    * ====================================================================
7    *
8    * Copyright (C) 2000-2002 bob mcwhirter & James Strachan.
9    * All rights reserved.
10   *
11   * Redistribution and use in source and binary forms, with or without
12   * modification, are permitted provided that the following conditions
13   * are met:
14   * 
15   * 1. Redistributions of source code must retain the above copyright
16   *    notice, this list of conditions, and the following disclaimer.
17   *
18   * 2. Redistributions in binary form must reproduce the above copyright
19   *    notice, this list of conditions, and the disclaimer that follows 
20   *    these conditions in the documentation and/or other materials 
21   *    provided with the distribution.
22   *
23   * 3. The name "Jaxen" must not be used to endorse or promote products
24   *    derived from this software without prior written permission.  For
25   *    written permission, please contact license@jaxen.org.
26   * 
27   * 4. Products derived from this software may not be called "Jaxen", nor
28   *    may "Jaxen" appear in their name, without prior written permission
29   *    from the Jaxen Project Management (pm@jaxen.org).
30   * 
31   * In addition, we request (but do not require) that you include in the 
32   * end-user documentation provided with the redistribution and/or in the 
33   * software itself an acknowledgement equivalent to the following:
34   *     "This product includes software developed by the
35   *      Jaxen Project (http://www.jaxen.org/)."
36   * Alternatively, the acknowledgment may be graphical using the logos 
37   * available at http://www.jaxen.org/
38   *
39   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
40   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
41   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
42   * DISCLAIMED.  IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT
43   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
45   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
46   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
47   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
48   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
49   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50   * SUCH DAMAGE.
51   *
52   * ====================================================================
53   * This software consists of voluntary contributions made by many 
54   * individuals on behalf of the Jaxen Project and was originally 
55   * created by bob mcwhirter <bob@werken.com> and 
56   * James Strachan <jstrachan@apache.org>.  For more information on the 
57   * Jaxen Project, please see <http://www.jaxen.org/>.
58   * 
59   * $Id: SubstringAfterFunction.java,v 1.8 2005/06/26 16:07:23 elharo Exp $
60   */
61  
62  
63  package org.jaxen.function;
64  
65  import java.util.List  ;
66  
67  import org.jaxen.Context;
68  import org.jaxen.Function;
69  import org.jaxen.FunctionCallException;
70  import org.jaxen.Navigator;
71  
72  /**
73   * <p><b>4.2</b> <code><i>string</i> substring-after(<i>string</i>,<i>string</i>)</code> 
74   * 
75   * 
76   * <blockquote SRC="http://www.w3.org/TR/xpath">
77   * The <b>substring-after</b> function returns the substring of the first argument string 
78   * that follows the first occurrence of the second argument string in the first 
79   * argument string, or the empty string if the first argument string does not contain the second argument string. 
80   * For example, substring-after("1999/04/01","/") returns 04/01, 
81   * and substring-after("1999/04/01","19") returns 99/04/01.
82   * </blockquote>
83   * 
84   * @author bob mcwhirter (bob @ werken.com)
85   * @see <a HREF="http://www.w3.org/TR/xpath#function-substring-after" target="_top">Section 4.2 of the XPath Specification</a>
86   */
87  public class SubstringAfterFunction implements Function
88  {
89  
90      /**
91       * Create a new <code>SubstringAfterFunction</code> object.
92       */
93      public SubstringAfterFunction() {}
94  
95  
96      /** 
97       * Returns the part of the string-value of the first item in <code>args</code>
98       * that follows the string-value of the second item in <code>args</code>;
99       * or the empty string if the second string is not a substring of the first string.
100      *
101      * @param context the context at the point in the
102      *         expression when the function is called
103      * @param args a list that contains two items
104      * 
105      * @return a <code>String</code> containing that 
106      *     part of the string-value of the first item in <code>args</code>
107      *     that comes before the string-value of the second item in <code>args</code>
108      * 
109      * @throws FunctionCallException if <code>args</code> does not have length two
110      */
111     public Object   call(Context context,
112                        List   args) throws FunctionCallException
113     {
114         if (args.size() == 2)
115         {
116             return evaluate( args.get(0),
117                              args.get(1),
118                              context.getNavigator() );
119         }
120 
121         throw new FunctionCallException( "substring-after() requires two arguments." );
122     }
123 
124 
125     /** 
126      * Returns the part of <code>strArg</code> that follows the first occurence 
127      * of <code>matchArg</code>; or the empty string if the 
128      * <code>strArg</code> does not contain <code>matchArg</code>
129      * 
130      * @param strArg the string from which the substring is extracted
131      * @param matchArg the string that marks the boundary of the substring
132      * @param nav the <code>Navigator</code> used to calculate the string-values of
133      *     the first two arguments
134      * 
135      * @return a <code>String</code> containing
136      *     the part of <code>strArg</code> that precedes the first occurence 
137      *     of <code>matchArg</code>
138      * 
139      */
140     public static String   evaluate(Object   strArg,
141                                   Object   matchArg,
142                                   Navigator nav)
143     {
144         String   str   = StringFunction.evaluate( strArg,
145                                                 nav );
146 
147         String   match = StringFunction.evaluate( matchArg,
148                                                 nav );
149     
150         int loc = str.indexOf(match);
151 
152         if ( loc < 0 )
153         {
154             return "";
155         }
156 
157         return str.substring(loc+match.length());
158     }
159 }
160
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags