mcs/class/System.Net.Http/System.Net.Http.Headers/HeaderInfo.cs

   1 //
   2 // HeaderInfo.cs
   3 //
   4 // Authors:
   5 //      Marek Safar  <marek.safar@gmail.com>
   6 //
   7 // Copyright (C) 2011 Xamarin Inc (http://www.xamarin.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System.Diagnostics;
  30 using System.Collections.Generic;
  31
  32 namespace System.Net.Http.Headers
  33 {
  34         delegate bool TryParseDelegate<T> (string value, out T result);
  35
  36         abstract class HeaderInfo
  37         {
  38                 class HeaderTypeInfo<T, U> : HeaderInfo where U : class
  39                 {
  40                         readonly TryParseDelegate<T> parser;
  41
  42                         public HeaderTypeInfo (string name, TryParseDelegate<T> parser, HttpHeaderKind headerKind)
  43                                 : base (name, headerKind)
  44                         {
  45                                 this.parser = parser;
  46                         }
  47
  48                         public override void AddToCollection (object collection, object value)
  49                         {
  50                                 Debug.Assert (AllowsMany);
  51
  52                                 var c = (HttpHeaderValueCollection<U>) collection;
  53                                 c.Add ((U) value);
  54                         }
  55
  56                         protected override object CreateCollection (HttpHeaders headers, HeaderInfo headerInfo)
  57                         {
  58                                 return new HttpHeaderValueCollection<U> (headers, headerInfo);
  59                         }
  60
  61                         public override List<string> ToStringCollection (object collection)
  62                         {
  63                                 if (collection == null)
  64                                         return null;
  65
  66                                 var c = (HttpHeaderValueCollection<U>) collection;
  67                                 if (c.Count == 0)
  68                                         return null;
  69
  70                                 var list = new List<string> ();
  71                                 foreach (var item in c) {
  72                                         list.Add (item.ToString ());
  73                                 }
  74
  75                                 return list;
  76                         }
  77
  78                         public override bool TryParse (string value, out object result)
  79                         {
  80                                 T tresult;
  81                                 bool b = parser (value, out tresult);
  82                                 result = tresult;
  83                                 return b;
  84                         }
  85                 }
  86
  87                 public bool AllowsMany;
  88                 public readonly HttpHeaderKind HeaderKind;
  89                 public readonly string Name;
  90
  91                 protected HeaderInfo (string name, HttpHeaderKind headerKind)
  92                 {
  93                         this.Name = name;
  94                         this.HeaderKind = headerKind;
  95                 }
  96
  97                 public static HeaderInfo CreateSingle<T> (string name, TryParseDelegate<T> parser, HttpHeaderKind headerKind)
  98                 {
  99                         return new HeaderTypeInfo<T, object> (name, parser, headerKind);
 100                 }
 101
 102                 public static HeaderInfo CreateMulti<T> (string name, TryParseDelegate<T> parser, HttpHeaderKind headerKind) where T : class
 103                 {
 104                         return new HeaderTypeInfo<T, T> (name, parser, headerKind) {
 105                                 AllowsMany = true,
 106                         };
 107                 }
 108
 109                 public object CreateCollection (HttpHeaders headers)
 110                 {
 111                         return CreateCollection (headers, this);
 112                 }
 113
 114                 public abstract void AddToCollection (object collection, object value);
 115                 protected abstract object CreateCollection (HttpHeaders headers, HeaderInfo headerInfo);
 116                 public abstract List<string> ToStringCollection (object collection);
 117                 public abstract bool TryParse (string value, out object result);
 118         }
 119 }