kafka-streams-internals-SinkNode.adoc

SinkNode — ProcessorNode with no Child Nodes

SinkNode is a custom ProcessorNode with no child processor nodes.

SinkNode is created exclusively when SinkNodeFactory is requested to build a processor node (when InternalTopologyBuilder is requested to build a topology of processor nodes).

SinkNode uses a TopicNameExtractor for dynamic routing when processing a record.

Processing Record — process Method

void process(final K key, final V value)

Note	process is part of ProcessorNode Contract to process a record.

process…​FIXME

Creating SinkNode Instance

SinkNode takes the following when created:

• Name of the sink

• TopicNameExtractor

• Kafka Serializer for keys

• Kafka Serializer for values

• StreamPartitioner

Adding Child Processor Node — addChild Method

void addChild(final ProcessorNode<?, ?> child)

Note	addChild is part of ProcessorNode Contract to add a child processor node.

addChild simply throws an UnsupportedOperationException with the following message:

sink node does not allow addChild

Initializing Processor Node — init Method

void init(final ProcessorContext context)

Note	init is part of ProcessorNode Contract to…​FIXME.

init…​FIXME

Describing Itself (Textual Representation) — toString Method

void toString(final ProcessorContext context)

Note	toString is part of ProcessorNode Contract for the human-friendly / textual representation of a ProcessorNode.

toString…​FIXME