1 #region Copyright notice and license 2 // Protocol Buffers - Google's data interchange format 3 // Copyright 2008 Google Inc. All rights reserved. 4 // 5 // Use of this source code is governed by a BSD-style 6 // license that can be found in the LICENSE file or at 7 // https://developers.google.com/open-source/licenses/bsd 8 #endregion 9 10 using System.Collections.Generic; 11 using System.Diagnostics; 12 13 namespace Google.Protobuf.Reflection 14 { 15 // Implementation note: The descriptors which don't derive from this class are FileDescriptor 16 // and FeatureSetDescriptor - the latter of which isn't a descriptor in exactly the same way 17 // that the others are anyway. 18 19 /// <summary> 20 /// Base class for nearly all descriptors, providing common functionality. 21 /// </summary> 22 [DebuggerDisplay("Type = {GetType().Name,nq}, FullName = {FullName}")] 23 public abstract class DescriptorBase : IDescriptor 24 { DescriptorBase(FileDescriptor file, string fullName, int index, FeatureSetDescriptor features)25 internal DescriptorBase(FileDescriptor file, string fullName, int index, FeatureSetDescriptor features) 26 { 27 File = file; 28 FullName = fullName; 29 Index = index; 30 Features = features; 31 } 32 33 /// <summary> 34 /// The feature set for this descriptor, including inherited features. 35 /// This is internal as external users should use the properties on individual 36 /// descriptor types (e.g. FieldDescriptor.IsPacked) rather than querying features directly. 37 /// </summary> 38 internal FeatureSetDescriptor Features { get; } 39 40 /// <value> 41 /// The index of this descriptor within its parent descriptor. 42 /// </value> 43 /// <remarks> 44 /// This returns the index of this descriptor within its parent, for 45 /// this descriptor's type. (There can be duplicate values for different 46 /// types, e.g. one enum type with index 0 and one message type with index 0.) 47 /// </remarks> 48 public int Index { get; } 49 50 /// <summary> 51 /// Returns the name of the entity (field, message etc) being described. 52 /// </summary> 53 public abstract string Name { get; } 54 55 /// <summary> 56 /// The fully qualified name of the descriptor's target. 57 /// </summary> 58 public string FullName { get; } 59 60 /// <value> 61 /// The file this descriptor was declared in. 62 /// </value> 63 public FileDescriptor File { get; } 64 65 /// <summary> 66 /// The declaration information about the descriptor, or null if no declaration information 67 /// is available for this descriptor. 68 /// </summary> 69 /// <remarks> 70 /// This information is typically only available for dynamically loaded descriptors, 71 /// for example within a protoc plugin where the full descriptors, including source info, 72 /// are passed to the code by protoc. 73 /// </remarks> 74 public DescriptorDeclaration Declaration => File.GetDeclaration(this); 75 76 /// <summary> 77 /// Retrieves the list of nested descriptors corresponding to the given field number, if any. 78 /// If the field is unknown or not a nested descriptor list, return null to terminate the search. 79 /// The default implementation returns null. 80 /// </summary> GetNestedDescriptorListForField(int fieldNumber)81 internal virtual IReadOnlyList<DescriptorBase> GetNestedDescriptorListForField(int fieldNumber) => null; 82 } 83 }