1 #region Copyright notice and license
2 // Protocol Buffers - Google's data interchange format
3 // Copyright 2008 Google Inc.  All rights reserved.
4 // https://developers.google.com/protocol-buffers/
5 //
6 // Redistribution and use in source and binary forms, with or without
7 // modification, are permitted provided that the following conditions are
8 // met:
9 //
10 //     * Redistributions of source code must retain the above copyright
11 // notice, this list of conditions and the following disclaimer.
12 //     * Redistributions in binary form must reproduce the above
13 // copyright notice, this list of conditions and the following disclaimer
14 // in the documentation and/or other materials provided with the
15 // distribution.
16 //     * Neither the name of Google Inc. nor the names of its
17 // contributors may be used to endorse or promote products derived from
18 // this software without specific prior written permission.
19 //
20 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 #endregion
32 
33 using System;
34 using System.Collections.Generic;
35 
36 namespace Google.Protobuf.Reflection
37 {
38     /// <summary>
39     /// Descriptor for an enum type in a .proto file.
40     /// </summary>
41     public sealed class EnumDescriptor : DescriptorBase
42     {
43         private readonly EnumDescriptorProto proto;
44         private readonly MessageDescriptor containingType;
45         private readonly IList<EnumValueDescriptor> values;
46         private readonly Type clrType;
47 
EnumDescriptor(EnumDescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int index, Type clrType)48         internal EnumDescriptor(EnumDescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int index, Type clrType)
49             : base(file, file.ComputeFullName(parent, proto.Name), index)
50         {
51             this.proto = proto;
52             this.clrType = clrType;
53             containingType = parent;
54 
55             if (proto.Value.Count == 0)
56             {
57                 // We cannot allow enums with no values because this would mean there
58                 // would be no valid default value for fields of this type.
59                 throw new DescriptorValidationException(this, "Enums must contain at least one value.");
60             }
61 
62             values = DescriptorUtil.ConvertAndMakeReadOnly(proto.Value,
63                                                            (value, i) => new EnumValueDescriptor(value, file, this, i));
64 
65             File.DescriptorPool.AddSymbol(this);
66         }
67 
68         internal EnumDescriptorProto Proto { get { return proto; } }
69 
70         /// <summary>
71         /// The brief name of the descriptor's target.
72         /// </summary>
73         public override string Name { get { return proto.Name; } }
74 
75         /// <summary>
76         /// The CLR type for this enum. For generated code, this will be a CLR enum type.
77         /// </summary>
78         public Type ClrType { get { return clrType; } }
79 
80         /// <value>
81         /// If this is a nested type, get the outer descriptor, otherwise null.
82         /// </value>
83         public MessageDescriptor ContainingType
84         {
85             get { return containingType; }
86         }
87 
88         /// <value>
89         /// An unmodifiable list of defined value descriptors for this enum.
90         /// </value>
91         public IList<EnumValueDescriptor> Values
92         {
93             get { return values; }
94         }
95 
96         /// <summary>
97         /// Finds an enum value by number. If multiple enum values have the
98         /// same number, this returns the first defined value with that number.
99         /// If there is no value for the given number, this returns <c>null</c>.
100         /// </summary>
FindValueByNumber(int number)101         public EnumValueDescriptor FindValueByNumber(int number)
102         {
103             return File.DescriptorPool.FindEnumValueByNumber(this, number);
104         }
105 
106         /// <summary>
107         /// Finds an enum value by name.
108         /// </summary>
109         /// <param name="name">The unqualified name of the value (e.g. "FOO").</param>
110         /// <returns>The value's descriptor, or null if not found.</returns>
FindValueByName(string name)111         public EnumValueDescriptor FindValueByName(string name)
112         {
113             return File.DescriptorPool.FindSymbol<EnumValueDescriptor>(FullName + "." + name);
114         }
115     }
116 }