com.datastrato.gravitino.messaging

Interface TopicCatalog

All Known Implementing Classes:

MessagingCatalog

@Evolving
public interface TopicCatalog

The TopicCatalog interface defines the public API for managing topic objects in a schema. If the catalog implementation supports topic objects, it should implement this interface.

Method Summary

Modifier and Type	Method and Description
Topic	alterTopic(NameIdentifier ident, TopicChange... changes) Apply the changes to a topic in the catalog.
Topic	createTopic(NameIdentifier ident, java.lang.String comment, DataLayout dataLayout, java.util.Map<java.lang.String,java.lang.String> properties) Create a topic in the catalog.
boolean	dropTopic(NameIdentifier ident) Drop a topic from the catalog.
NameIdentifier[]	listTopics(Namespace namespace) List the topics in a schema namespace from the catalog.
Topic	loadTopic(NameIdentifier ident) Load topic metadata by NameIdentifier from the catalog.
default boolean	topicExists(NameIdentifier ident) Check if a topic exists using an NameIdentifier from the catalog.

Method Detail

listTopics

NameIdentifier[] listTopics(Namespace namespace)
                     throws NoSuchSchemaException

List the topics in a schema namespace from the catalog.

Parameters:

namespace - A schema namespace.

Returns:

An array of topic identifiers in the namespace.

Throws:

NoSuchSchemaException - If the schema does not exist.

loadTopic

Topic loadTopic(NameIdentifier ident)
         throws NoSuchTopicException

Load topic metadata by NameIdentifier from the catalog.

Parameters:

ident - A topic identifier.

Returns:

The topic metadata.

Throws:

NoSuchTopicException - If the topic does not exist.

topicExists

default boolean topicExists(NameIdentifier ident)

Check if a topic exists using an NameIdentifier from the catalog.

Parameters:

ident - A topic identifier.

Returns:

true If the topic exists, false otherwise.

createTopic

Topic createTopic(NameIdentifier ident,
                  java.lang.String comment,
                  DataLayout dataLayout,
                  java.util.Map<java.lang.String,java.lang.String> properties)
           throws NoSuchSchemaException,
                  TopicAlreadyExistsException

Create a topic in the catalog.

Parameters:

ident - A topic identifier.

comment - The comment of the topic object. Null is set if no comment is specified.

dataLayout - The message schema of the topic object. Always null because it's not supported yet.

properties - The properties of the topic object. Empty map is set if no properties are specified.

Returns:

The topic metadata.

Throws:

NoSuchSchemaException - If the schema does not exist.

TopicAlreadyExistsException - If the topic already exists.

alterTopic

Topic alterTopic(NameIdentifier ident,
                 TopicChange... changes)
          throws NoSuchTopicException,
                 java.lang.IllegalArgumentException

Apply the changes to a topic in the catalog.

Parameters:

ident - A topic identifier.

changes - The changes to apply to the topic.

Returns:

The altered topic metadata.

Throws:

NoSuchTopicException - If the topic does not exist.

java.lang.IllegalArgumentException - If the changes is rejected by the implementation.

dropTopic

boolean dropTopic(NameIdentifier ident)

Drop a topic from the catalog.

Parameters:

ident - A topic identifier.

Returns:

true If the topic is dropped, false if the topic does not exist.