objectivec/GPBExtensionRegistry.h

   1 // Protocol Buffers - Google's data interchange format
   2 // Copyright 2008 Google Inc.  All rights reserved.
   3 //
   4 // Use of this source code is governed by a BSD-style
   5 // license that can be found in the LICENSE file or at
   6 // https://developers.google.com/open-source/licenses/bsd
   7
   8 #import <Foundation/Foundation.h>
   9
  10 #import "GPBDescriptor.h"
  11
  12 NS_ASSUME_NONNULL_BEGIN
  13
  14 /**
  15  * A table of known extensions, searchable by name or field number.  When
  16  * parsing a protocol message that might have extensions, you must provide a
  17  * GPBExtensionRegistry in which you have registered any extensions that you
  18  * want to be able to parse. Otherwise, those extensions will just be treated
  19  * like unknown fields.
  20  **/
  21 @protocol GPBExtensionRegistry <NSObject>
  22
  23 /**
  24  * Looks for the extension registered for the given field number on a given
  25  * GPBDescriptor.
  26  *
  27  * @param descriptor  The descriptor to look for a registered extension on.
  28  * @param fieldNumber The field number of the extension to look for.
  29  *
  30  * @return The registered GPBExtensionDescriptor or nil if none was found.
  31  **/
  32 - (nullable GPBExtensionDescriptor *)extensionForDescriptor:(GPBDescriptor *)descriptor
  33                                                 fieldNumber:(NSInteger)fieldNumber;
  34 @end
  35
  36 /**
  37  * A concrete implementation of `GPBExtensionRegistry`.
  38  *
  39  * The *Root classes provide `+extensionRegistry` for the extensions defined
  40  * in a given file *and* all files it imports. You can also create a
  41  * GPBExtensionRegistry, and merge those registries to handle parsing
  42  * extensions defined from non overlapping files.
  43  *
  44  * ```
  45  * GPBExtensionRegistry *registry = [[MyProtoFileRoot extensionRegistry] copy];
  46  * [registry addExtension:[OtherMessage neededExtension]]; // Not in MyProtoFile
  47  * NSError *parseError;
  48  * MyMessage *msg = [MyMessage parseData:data extensionRegistry:registry error:&parseError];
  49  * ```
  50  **/
  51 __attribute__((objc_subclassing_restricted))
  52 @interface GPBExtensionRegistry : NSObject<NSCopying, GPBExtensionRegistry>
  53
  54 /**
  55  * Adds the given GPBExtensionDescriptor to this registry.
  56  *
  57  * @param extension The extension description to add.
  58  **/
  59 - (void)addExtension:(GPBExtensionDescriptor *)extension;
  60
  61 /**
  62  * Adds all the extensions from another registry to this registry.
  63  *
  64  * @param registry The registry to merge into this registry.
  65  **/
  66 - (void)addExtensions:(GPBExtensionRegistry *)registry;
  67
  68 @end
  69
  70 NS_ASSUME_NONNULL_END