| Interface | Description | 
|---|---|
| DataLayout | 
 The interface for message schema of a topic. 
 | 
| Topic | 
 An interface representing a topic under a schema  
Namespace. | 
| TopicCatalog | 
 The  
TopicCatalog interface defines the public API for managing topic objects in a schema. | 
| TopicChange | 
 A topic change is a change to a topic. 
 | 
| Class | Description | 
|---|---|
| TopicChange.RemoveProperty | 
 A topic change to remove a property from the topic. 
 | 
| TopicChange.SetProperty | 
 A topic change to set or update the property and value for the topic. 
 | 
| TopicChange.UpdateTopicComment | 
 A topic change to update the topic comment. 
 |