summaryrefslogtreecommitdiff
path: root/lib/prado/framework/Collections/TDummyDataSource.php
blob: 275d847312aaedb16e5f5aa33307cd46a246f560 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
<?php
/**
 * TDummyDataSource, TDummyDataSourceIterator classes
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link https://github.com/pradosoft/prado
 * @copyright Copyright &copy; 2005-2016 The PRADO Group
 * @license https://github.com/pradosoft/prado/blob/master/COPYRIGHT
 * @package System.Collections
 */

/**
 * TDummyDataSource class
 *
 * TDummyDataSource implements a dummy data collection with a specified number
 * of dummy data items. The number of virtual items can be set via
 * {@link setCount Count} property. You can traverse it using <b>foreach</b>
 * PHP statement like the following,
 * <code>
 * foreach($dummyDataSource as $dataItem)
 * </code>
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package System.Collections
 * @since 3.0
 */
class TDummyDataSource extends TComponent implements IteratorAggregate, Countable
{
	private $_count;

	/**
	 * Constructor.
	 * @param integer number of (virtual) items in the data source.
	 */
	public function __construct($count)
	{
		$this->_count=$count;
	}

	/**
	 * @return integer number of (virtual) items in the data source.
	 */
	public function getCount()
	{
		return $this->_count;
	}

	/**
	 * @return Iterator iterator
	 */
	public function getIterator()
	{
		return new TDummyDataSourceIterator($this->_count);
	}

	/**
	 * Returns the number of (virtual) items in the data source.
	 * This method is required by Countable interface.
	 * @return integer number of (virtual) items in the data source.
	 */
	public function count()
	{
		return $this->getCount();
	}
}

/**
 * TDummyDataSourceIterator class
 *
 * TDummyDataSourceIterator implements Iterator interface.
 *
 * TDummyDataSourceIterator is used by {@link TDummyDataSource}.
 * It allows TDummyDataSource to return a new iterator
 * for traversing its dummy items.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package System.Collections
 * @since 3.0
 */
class TDummyDataSourceIterator implements Iterator
{
	private $_index;
	private $_count;

	/**
	 * Constructor.
	 * @param integer number of (virtual) items in the data source.
	 */
	public function __construct($count)
	{
		$this->_count=$count;
		$this->_index=0;
	}

	/**
	 * Rewinds internal array pointer.
	 * This method is required by the interface Iterator.
	 */
	public function rewind()
	{
		$this->_index=0;
	}

	/**
	 * Returns the key of the current array item.
	 * This method is required by the interface Iterator.
	 * @return integer the key of the current array item
	 */
	public function key()
	{
		return $this->_index;
	}

	/**
	 * Returns the current array item.
	 * This method is required by the interface Iterator.
	 * @return mixed the current array item
	 */
	public function current()
	{
		return null;
	}

	/**
	 * Moves the internal pointer to the next array item.
	 * This method is required by the interface Iterator.
	 */
	public function next()
	{
		$this->_index++;
	}

	/**
	 * Returns whether there is an item at current position.
	 * This method is required by the interface Iterator.
	 * @return boolean
	 */
	public function valid()
	{
		return $this->_index<$this->_count;
	}
}