gee/readonlycollection.vala

   1 /* readonlycollection.vala
   2  *
   3  * Copyright (C) 2007-2008  Jürg Billeter
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  18  *
  19  * Author:
  20  *      Jürg Billeter <j@bitron.ch>
  21  */
  22
  23 using GLib;
  24
  25 /**
  26  * Represents a read-only collection of items.
  27  */
  28 public class Gee.ReadOnlyCollection<G> : CollectionObject, Iterable<G>, Collection<G> {
  29         public int size {
  30                 get { return _collection.size; }
  31         }
  32
  33         public Collection<G> collection {
  34                 set { _collection = value; }
  35         }
  36
  37         private Collection<G> _collection;
  38
  39         public ReadOnlyCollection (Collection<G>? collection = null) {
  40                 this.collection = collection;
  41         }
  42
  43         public Type get_element_type () {
  44                 return typeof (G);
  45         }
  46
  47         public Gee.Iterator<G> iterator () {
  48                 if (_collection == null) {
  49                         return new Iterator<G> ();
  50                 }
  51
  52                 return _collection.iterator ();
  53         }
  54
  55         public bool contains (G item) {
  56                 if (_collection == null) {
  57                         return false;
  58                 }
  59
  60                 return _collection.contains (item);
  61         }
  62
  63         public bool add (G item) {
  64                 assert_not_reached ();
  65         }
  66
  67         public bool remove (G item) {
  68                 assert_not_reached ();
  69         }
  70
  71         public void clear () {
  72                 assert_not_reached ();
  73         }
  74
  75         private class Iterator<G> : CollectionObject, Gee.Iterator<G> {
  76                 public bool next () {
  77                         return false;
  78                 }
  79
  80                 public G? get () {
  81                         return null;
  82                 }
  83         }
  84 }
  85