Chapter 142. Hazelcast Topic Component Available as of Camel version 2.15 The Hazelcast Topic component is one of Camel Hazelcast Components which allows you to access Hazelcast distributed topic. 142.1. Options The Hazelcast Topic component supports 3 options, which are listed below. Name Description Default Type hazelcastInstance (advanced) The hazelcast instance reference which can be used for hazelcast endpoint. If you don't specify the instance reference, camel use the default hazelcast instance from the camel-hazelcast instance. HazelcastInstance hazelcastMode (advanced) The hazelcast mode reference which kind of instance should be used. If you don't specify the mode, then the node mode will be the default. node String resolveProperty Placeholders (advanced) Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders. true boolean The Hazelcast Topic endpoint is configured using URI syntax: with the following path and query parameters: 142.1.1. Path Parameters (1 parameters): Name Description Default Type cacheName Required The name of the cache String 142.1.2. Query Parameters (16 parameters): Name Description Default Type defaultOperation (common) To specify a default operation to use, if no operation header has been provided. HazelcastOperation hazelcastInstance (common) The hazelcast instance reference which can be used for hazelcast endpoint. HazelcastInstance hazelcastInstanceName (common) The hazelcast instance reference name which can be used for hazelcast endpoint. If you don't specify the instance reference, camel use the default hazelcast instance from the camel-hazelcast instance. String reliable (common) Define if the endpoint will use a reliable Topic struct or not. false boolean bridgeErrorHandler (consumer) Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. false boolean pollingTimeout (consumer) Define the polling timeout of the Queue consumer in Poll mode 10000 long poolSize (consumer) Define the Pool size for Queue Consumer Executor 1 int queueConsumerMode (consumer) Define the Queue Consumer mode: Listen or Poll Listen HazelcastQueueConsumer Mode exceptionHandler (consumer) To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. ExceptionHandler exchangePattern (consumer) Sets the exchange pattern when the consumer creates an exchange. ExchangePattern synchronous (advanced) Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). false boolean concurrentConsumers (seda) To use concurrent consumers polling from the SEDA queue. 1 int onErrorDelay (seda) Milliseconds before consumer continues polling after an error has occurred. 1000 int pollTimeout (seda) The timeout used when consuming from the SEDA queue. When a timeout occurs, the consumer can check whether it is allowed to continue running. Setting a lower value allows the consumer to react more quickly upon shutdown. 1000 int transacted (seda) If set to true then the consumer runs in transaction mode, where the messages in the seda queue will only be removed if the transaction commits, which happens when the processing is complete. false boolean transferExchange (seda) If set to true the whole Exchange will be transfered. If header or body contains not serializable objects, they will be skipped. false boolean 142.2. Spring Boot Auto-Configuration The component supports 8 options, which are listed below. Name Description Default Type camel.component.hazelcast-topic.customizer.hazelcast-instance.enabled Enable or disable the cache-manager customizer. true Boolean camel.component.hazelcast-topic.customizer.hazelcast-instance.enabled Enable or disable the cache-manager customizer. true Boolean camel.component.hazelcast-topic.customizer.hazelcast-instance.override Configure if the cache manager eventually set on the component should be overridden by the customizer. false Boolean camel.component.hazelcast-topic.customizer.hazelcast-instance.override Configure if the cache manager eventually set on the component should be overridden by the customizer. false Boolean camel.component.hazelcast-topic.enabled Enable hazelcast-topic component true Boolean camel.component.hazelcast-topic.hazelcast-instance The hazelcast instance reference which can be used for hazelcast endpoint. If you don't specify the instance reference, camel use the default hazelcast instance from the camel-hazelcast instance. The option is a com.hazelcast.core.HazelcastInstance type. String camel.component.hazelcast-topic.hazelcast-mode The hazelcast mode reference which kind of instance should be used. If you don't specify the mode, then the node mode will be the default. node String camel.component.hazelcast-topic.resolve-property-placeholders Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders. true Boolean 142.3. Topic producer - to("hazelcast-topic:foo") The topic producer provides only one operation (publish). 142.3.1. Sample for publish : from("direct:add") .setHeader(HazelcastConstants.OPERATION, constant(HazelcastOperation.PUBLISH)) .toF("hazelcast-%sbar", HazelcastConstants.PUBLISH_OPERATION); 142.4. Topic consumer - from("hazelcast-topic:foo") The topic consumer provides only one operation (received). This component is supposed to support multiple consumption as it's expected when it comes to topics so you are free to have as much consumers as you need on the same hazelcast topic. fromF("hazelcast-%sfoo", HazelcastConstants.TOPIC_PREFIX) .choice() .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.RECEIVED)) .log("...message received") .otherwise() .log("...this should never have happened")

Commands:
hazelcast-topic:cacheName
from("direct:add") .setHeader(HazelcastConstants.OPERATION, constant(HazelcastOperation.PUBLISH)) .toF("hazelcast-%sbar", HazelcastConstants.PUBLISH_OPERATION);
fromF("hazelcast-%sfoo", HazelcastConstants.TOPIC_PREFIX) .choice() .when(header(HazelcastConstants.LISTENER_ACTION).isEqualTo(HazelcastConstants.RECEIVED)) .log("...message received") .otherwise() .log("...this should never have happened")