src/Boo.Lang/Runtime/MethodDispatcherFactory.cs

   1 #region license
   2 // Copyright (c) 2004, 2007 Rodrigo B. de Oliveira (rbo@acm.org)
   3 // All rights reserved.
   4 //
   5 // Redistribution and use in source and binary forms, with or without modification,
   6 // are permitted provided that the following conditions are met:
   7 //
   8 //       * Redistributions of source code must retain the above copyright notice,
   9 //       this list of conditions and the following disclaimer.
  10 //       * Redistributions in binary form must reproduce the above copyright notice,
  11 //       this list of conditions and the following disclaimer in the documentation
  12 //       and/or other materials provided with the distribution.
  13 //       * Neither the name of Rodrigo B. de Oliveira nor the names of its
  14 //       contributors may be used to endorse or promote products derived from this
  15 //       software without specific prior written permission.
  16 //
  17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
  18 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
  21 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  24 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  25 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26 // THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27 #endregion
  28
  29 using System;
  30 using System.Reflection;
  31 using System.Collections.Generic;
  32
  33 namespace Boo.Lang.Runtime
  34 {
  35         public class MethodDispatcherFactory : AbstractDispatcherFactory
  36         {
  37                 public MethodDispatcherFactory(ExtensionRegistry extensions, object target, Type type, string methodName, params object[] arguments) : base(extensions, target, type, methodName, arguments)
  38                 {
  39                 }
  40
  41                 public Dispatcher Create()
  42                 {
  43                         Type[] types = GetArgumentTypes();
  44                         CandidateMethod found = ResolveMethod(types);
  45                         if (null != found) return EmitMethodDispatcher(found, types);
  46                         return ProduceExtensionDispatcher();
  47                 }
  48
  49                 private Dispatcher ProduceExtensionDispatcher()
  50                 {
  51                         CandidateMethod found = ResolveExtensionMethod();
  52                         if (found == null) throw new System.MissingMethodException(_type.FullName, _name);
  53                         return EmitExtensionDispatcher(found);
  54                 }
  55
  56                 private CandidateMethod ResolveExtensionMethod()
  57                 {
  58                         return ResolveExtension(GetExtensionMethods());
  59                 }
  60
  61                 private CandidateMethod ResolveMethod(Type[] argumentTypes)
  62                 {
  63                         return ResolveMethod(argumentTypes, GetCandidates());
  64                 }
  65
  66                 private IEnumerable<MethodInfo> GetCandidates()
  67                 {
  68                         foreach (MethodInfo method in _type.GetMethods(RuntimeServices.DefaultBindingFlags))
  69                         {
  70                                 if (_name != method.Name) continue;
  71                                 yield return method;
  72                         }
  73                 }
  74
  75                 private Dispatcher EmitMethodDispatcher(CandidateMethod found, Type[] argumentTypes)
  76                 {
  77                         return new MethodDispatcherEmitter(_type, found, argumentTypes).Emit();
  78                 }
  79         }
  80 }