Get Index API

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Get Index Request

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A GetIndexRequest requires one or more index arguments:

GetIndexRequest request = new GetIndexRequest().indices("index"); 

The index whose information we want to retrieve

Optional arguments

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The following arguments can optionally be provided:

request.includeDefaults(true); 

If true, defaults will be returned for settings not explicitly set on the index

request.indicesOptions(IndicesOptions.lenientExpandOpen()); 

Setting IndicesOptions controls how unavailable indices are resolved and how wildcard expressions are expanded

Synchronous Execution

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GetIndexResponse getIndexResponse = client.indices().get(request, RequestOptions.DEFAULT);

Asynchronous Execution

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The asynchronous execution of a Get Index request requires both the GetIndexRequest instance and an ActionListener instance to be passed to the asynchronous method:

client.indices().getAsync(request, RequestOptions.DEFAULT, listener); 

The GetIndexRequest to execute and the ActionListener to use when the execution completes

The asynchronous method does not block and returns immediately. Once it is completed the ActionListener is called back using the onResponse method if the execution successfully completed or using the onFailure method if it failed.

A typical listener for GetIndexResponse looks like:

ActionListener<GetIndexResponse> listener =
    new ActionListener<GetIndexResponse>() {
        @Override
        public void onResponse(GetIndexResponse getIndexResponse) {
            
        }

        @Override
        public void onFailure(Exception e) {
            
        }
    };

Called when the execution is successfully completed. The response is provided as an argument.

Called in case of failure. The raised exception is provided as an argument.

Get Index Response

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The returned GetIndexResponse allows to retrieve information about the executed operation as follows:

ImmutableOpenMap<String, MappingMetaData> indexMappings = getIndexResponse.getMappings().get("index"); 
Map<String, Object> indexTypeMappings = indexMappings.get("doc").getSourceAsMap(); 
List<AliasMetaData> indexAliases = getIndexResponse.getAliases().get("index"); 
String numberOfShardsString = getIndexResponse.getSetting("index", "index.number_of_shards"); 
Settings indexSettings = getIndexResponse.getSettings().get("index"); 
Integer numberOfShards = indexSettings.getAsInt("index.number_of_shards", null); 
TimeValue time = getIndexResponse.defaultSettings().get("index")
    .getAsTime("index.refresh_interval", null); 

Retrieve a Map of different types to MappingMetadata for index.

Retrieve a Map for the properties for document type doc.

Get the list of aliases for index.

Get the value for the setting string index.number_of_shards for index. If the setting was not explicitly specified but was part of the default settings (and includeDefault was true) then the default setting would be retrieved.

Retrieve all settings for index.

The Settings objects gives more flexibility. Here it is used to extract the setting index.number_of_shards as an integer.

Get the default setting index.refresh_interval (if includeDefault was set to true). If includeDefault was set to false, getIndexResponse.defaultSettings() will return an empty map.