base/struct.php

   1 <?php
   2 // Hoplite
   3 // Copyright (c) 2011 Blue Static
   4 //
   5 // This program is free software: you can redistribute it and/or modify it
   6 // under the terms of the GNU General Public License as published by the Free
   7 // Software Foundation, either version 3 of the License, or any later version.
   8 //
   9 // This program is distributed in the hope that it will be useful, but WITHOUT
  10 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 // more details.
  13 //
  14 // You should have received a copy of the GNU General Public License along with
  15 // this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 namespace hoplite\base;
  18
  19 /*!
  20   A struct can be used to maintain a list of properties. Any properties not
  21   strictly defined in the |$fields| array will throw exceptions when accessed.
  22 */
  23 class Struct
  24 {
  25   /*! @var array The fields of this struct. */
  26   protected $fields = array();
  27
  28   /*! @var array The data that corresponds to the |$fields|. */
  29   protected $data = array();
  30
  31   /*!
  32     Creates a new Struct, optionally initializing the data members from an
  33     iterable object.
  34   */
  35   public function __construct($data = array())
  36   {
  37     foreach ($data as $key => $value)
  38       if (!in_array($key, $this->fields))
  39         throw new StructException('Invalid field "' . $key . '"');
  40       else
  41         $this->data[$key] = $value;
  42   }
  43
  44   /*! Gets a specified key. This can return NULL. */
  45   public function __get($key)
  46   {
  47     if (!in_array($key, $this->fields))
  48       throw new StructException('Invalid field "' . $key . '"');
  49
  50     if (!isset($this->data[$key]))
  51       return NULL;
  52
  53     return $this->data[$key];
  54   }
  55   public function Get($key) { return $this->__get($key); }
  56
  57   /*! Sets the specified key-value pair. */
  58   public function __set($key, $value)
  59   {
  60     if (!in_array($key, $this->fields))
  61       throw new StructException('Cannot set value for invalid field "' . $key . '"');
  62     $this->data[$key] = $value;
  63   }
  64   public function Set($key, $value) { $this->__set($key, $value); }
  65
  66   /*! Takes values from an array or object and sets the relevant values. */
  67   public function SetFrom($array)
  68   {
  69     foreach ($array as $key => $value)
  70       if (in_array($key, $this->fields))
  71         $this->data[$key] = $value;
  72   }
  73
  74   /*! Returns the data members as an array. */
  75   public function ToArray()
  76   {
  77     return $this->data;
  78   }
  79
  80   /*! Returns the number of members in the struct. */
  81   public function Count()
  82   {
  83     return count($this->fields);
  84   }
  85
  86   /*! Returns the list of fields the Struct has. */
  87   public function GetFields()
  88   {
  89     return $this->fields;
  90   }
  91 }
  92
  93 class StructException extends \Exception {}