ElasticSearch--------------------->elasticsearch Clients--------------------->java REST Client API

Elasticsearch-->java REST Client API Overview:

Elasticsearch provides the rest web API, so developers can call Elasticsearch in their own restful web

For a detailed description of the Java Rest client API, see the official Documentation:java Rest Client API

You can call Elasticsearch directly using curl:

basic Syntax Format: RESTful API with JSON over HTTP

Use example:

For example, to calculate the number of files in a cluster, we can use this

curl-xget ' http://localhost:9200/_count?pretty '-d ' {"Query": {"Match_all": {}}} ' /span>

Elasticsearch returns an HTTP status code (for example:200 OK ') and (in addition to ' HEAD ' request) a JSON-formatted return value. The previous ' Curl  request will return a JSON body like the following:

{"Count": 0, "_shards": { "Total": 5, "successful": 5, "failed": 0}}

did not see the HTTP header information in the returned results because we did not requirecurl" shows them. To see the header information, you need to combine '-I  parameters to use  curl  command:

curl-i-xget ' Http://localhost:9200/_count?pretty '-d '

  {"Query": {"Match_ All ": {}} '  

ElasticSearch--------------------->elasticsearch clients--------------------->java REST Client API