elasticsearch/docs/java-rest/high-level/indices/get_settings.asciidoc

[[java-rest-high-get-settings]]
=== Get Settings API

[[java-rest-high-get-settings-request]]
==== Get Settings Request

A `GetSettingsRequest` requires one or more `index` arguments:

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<1> The index whose settings we should retrieve

==== Optional arguments
The following arguments can optionally be provided:

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<1> One or more settings that be the only settings retrieved.  If unset, all settings will be retrieved

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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-settings-request-include-defaults]
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<1> If true, defaults will be returned for settings not explicitly set on the index

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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-settings-request-indicesOptions]
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<1> Setting `IndicesOptions` controls how unavailable indices are resolved and
how wildcard expressions are expanded

[[java-rest-high-get-settings-sync]]
==== Synchronous Execution

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[[java-rest-high-get-settings-async]]
==== Asynchronous Execution

The asynchronous execution of a Get Settings request requires both the `GetSettingsRequest`
instance and an `ActionListener` instance to be passed to the asynchronous
method:

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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-settings-execute-async]
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<1> The `GetSettingsRequest` 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 `GetSettingsResponse` looks like:

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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-settings-execute-listener]
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<1> Called when the execution is successfully completed. The response is
provided as an argument
<2> Called in case of failure. The raised exception is provided as an argument

[[java-rest-high-get-settings-response]]
==== Get Settings Response

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

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<1> We can retrieve the setting value for a particular index directly from the response as a string
<2> We can also retrieve the Settings object for a particular index for further examination
<3> The returned Settings object provides convenience methods for non String types

If the `includeDefaults` flag was set to true in the `GetSettingsRequest`, the 
behavior of `GetSettingsResponse` will differ somewhat.

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-settings-defaults-response]
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<1> Individual default setting values may be retrieved directly from the `GetSettingsResponse`
<2> We may retrieve a Settings object for an index that contains those settings with default values