Rest client can perform Synchronous and Asynchronous both type of requests. Synchronous Api’s return response with response code while Asynchronous api’s return response as void and accept extra argument extraResponseListener as callback which respond on completion and failure.

Synchronous  performRequest

Response performRequest(String method, String endpoint, Header... headers) throws IOException;

Response performRequest(String method, String endpoint, Map<String, String> params, Header... headers) throws IOException;

Response performRequest(String method, String endpoint, Map<String, String> params, HttpEntity entity, Header... headers) throws IOException;

Response performRequest(String method, String endpoint, Map<String, String> params, HttpEntity entity, HttpAsyncResponseConsumerFactory responseConsumerFactory, Header... headers) throws IOException;

Asynchronous  performRequest

void performRequestAsync(String method, String endpoint, ResponseListener responseListener, Header... headers);

void performRequestAsync(String method, String endpoint, Map<String, String> params, ResponseListener responseListener, Header... headers);

void performRequestAsync(String method, String endpoint, Map<String, String> params, HttpEntity entity, ResponseListener responseListener, Header... headers);

void performRequestAsync(String method, String endpoint, Map<String, String> params, HttpEntity entity, HttpAsyncResponseConsumerFactory responseConsumerFactory, ResponseListener responseListener, Header... headers);

Details about Parameters:

Method :  Elasticsearch support all rest opration like GET, POST,PUT,DELETE.
Endpoint: Url to call elasticsearch apis like (/_cat/indices for getting list of indexes on elasticsearch).
Params: This field is optional and will pass as query strings parameter.
Entity: This field is optional and will pass in method type like POST,PUT or filter query request.
Headers: This is optional will pass if request need header param.

Additional Parameter for Asynchronous call:

ResponseConsumerFactory: Optional and will use to create HttpAsynchResponseConsumer for callback response for request.

ResponseListener: Listener return callback response as request was complete successfully or failure.

Read More on Elasticsearch REST

• Elasticsearch REST API and Configuration
• Elasticsearch REST Java Connection Client
• Elasticsearch REST Response Handling
• Elasticsearch REST JAVA Client for Cluster Detail
• Elasticsearch REST JAVA Client to get Index Details List

Integration

Integrate Filebeat, Kafka, Logstash, Elasticsearch and Kibana