8 * Copyright (c) 2009-2013 Nicholas J Humfrey. All rights reserved.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright notice,
15 * this list of conditions and the following disclaimer in the documentation
16 * and/or other materials provided with the distribution.
17 * 3. The name of the author 'Nicholas J Humfrey" may be used to endorse or
18 * promote products derived from this software without specific prior
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
34 * @copyright Copyright (c) 2009-2013 Nicholas J Humfrey
35 * @license http://www.opensource.org/licenses/bsd-license.php
39 * Class that represents an RDF Literal of datatype xsd:date
42 * @link http://www.w3.org/TR/xmlschema-2/#date
43 * @copyright Copyright (c) 2009-2013 Nicholas J Humfrey
44 * @license http://www.opensource.org/licenses/bsd-license.php
46 class EasyRdf_Literal_Date extends EasyRdf_Literal
48 /** Constructor for creating a new date literal
50 * If the value is a DateTime object, then it will be converted to the xsd:date format.
51 * If no value is given or is is null, then the current date is used.
55 * @param mixed $value The value of the literal
56 * @param string $lang Should be null (literals with a datatype can't have a language)
57 * @param string $datatype Optional datatype (default 'xsd:date')
58 * @return object EasyRdf_Literal_Date
60 public function __construct($value = null, $lang = null, $datatype = null)
62 // If $value is null, use today's date
63 if (is_null($value)) {
64 $value = new DateTime('today');
67 // Convert DateTime object into string
68 if ($value instanceof DateTime) {
69 $value = $value->format('Y-m-d');
72 parent::__construct($value, null, $datatype);
75 /** Parses a string using DateTime and creates a new literal
78 * $date = EasyRdf_Literal_Date::parse('1 January 2011');
81 * @param string $value The date to parse
82 * @return object EasyRdf_Literal_Date
84 public static function parse($value)
86 $value = new DateTime($value);
87 return new EasyRdf_Literal_Date($value);
90 /** Returns the date as a PHP DateTime object
92 * @see DateTime::format
95 public function getValue()
97 return new DateTime($this->value);
100 /** Returns date formatted according to given format
102 * @see DateTime::format
103 * @param string $format
106 public function format($format)
108 return $this->getValue()->format($format);
111 /** A full integer representation of the year, 4 digits
115 public function year()
117 return (int)$this->format('Y');
120 /** Integer representation of the month
124 public function month()
126 return (int)$this->format('m');
129 /** Integer representation of the day of the month
133 public function day()
135 return (int)$this->format('d');