View Javadoc

1   /*
2    * $Id: PropertyValidator.java [15-May-2004]
3    *
4    * Copyright (c) 2004, Ben Fortuna
5    * All rights reserved.
6    *
7    * Redistribution and use in source and binary forms, with or without
8    * modification, are permitted provided that the following conditions
9    * are met:
10   *
11   * 	o Redistributions of source code must retain the above copyright
12   * notice, this list of conditions and the following disclaimer.
13   *
14   * 	o Redistributions in binary form must reproduce the above copyright
15   * notice, this list of conditions and the following disclaimer in the
16   * documentation and/or other materials provided with the distribution.
17   *
18   * 	o Neither the name of Ben Fortuna nor the names of any other contributors
19   * may be used to endorse or promote products derived from this software
20   * without specific prior written permission.
21   *
22   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25   * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
26   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
29   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33   */
34  package net.fortuna.ical4j.util;
35  
36  import net.fortuna.ical4j.model.PropertyList;
37  import net.fortuna.ical4j.model.ValidationException;
38  
39  /***
40   * Defines methods for validating properties and property lists.
41   *
42   * @author benfortuna
43   */
44  public final class PropertyValidator {
45  
46      private static PropertyValidator instance = new PropertyValidator();
47  
48      /***
49       * Constructor made private to enforce singleton.
50       */
51      private PropertyValidator() {
52      }
53  
54      /***
55       * Ensure a property occurs no more than once.
56       *
57       * @param propertyName
58       *            the property name
59       * @param properties
60       *            a list of properties to query
61       * @throws ValidationException
62       *             when the specified property occurs more than once
63       */
64      public void validateOneOrLess(final String propertyName,
65              final PropertyList properties) throws ValidationException {
66  
67          if (properties.getProperties(propertyName).size() > 1) {
68              throw new ValidationException(
69                  "Property [" + propertyName + "] must only be specified once");
70          }
71      }
72  
73      /***
74       * Ensure a property occurs at least once.
75       *
76       * @param propertyName
77       *            the property name
78       * @param properties
79       *            a list of properties to query
80       * @throws ValidationException
81       *             when the specified property occurs more than once
82       */
83      public void validateOneOrMore(final String propertyName,
84              final PropertyList properties) throws ValidationException {
85  
86          if (properties.getProperties(propertyName).size() < 1) {
87              throw new ValidationException(
88                  "Property [" + propertyName
89                          + "] must be specified at least once");
90          }
91      }
92  
93      /***
94       * Ensure a property occurs once.
95       *
96       * @param propertyName
97       *            the property name
98       * @param properties
99       *            a list of properties to query
100      * @throws ValidationException
101      *             when the specified property does not occur once
102      */
103     public void validateOne(final String propertyName,
104             final PropertyList properties) throws ValidationException {
105 
106         if (properties.getProperties(propertyName).size() != 1) {
107             throw new ValidationException(
108                 "Property [" + propertyName + "] must be specified once");
109         }
110     }
111 
112     /***
113      * @return Returns the instance.
114      */
115     public static PropertyValidator getInstance() {
116         return instance;
117     }
118 }