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

[[java-rest-high-get-field-mappings]]
=== Get Field Mappings API

[[java-rest-high-get-field-mappings-request]]
==== Get Field Mappings Request

A `GetFieldMappingsRequest` can have an optional list of indices, optional list of types and the list of fields:

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-request]
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<1> An empty request
<2> Setting the indices to fetch mapping for
<3> The types to be returned
<4> The fields to be returned

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

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-request-indicesOptions]
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<1> Setting `IndicesOptions` controls how unavailable indices are resolved and
how wildcard expressions are expanded

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-request-local]
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<1> The `local` flag (defaults to `false`) controls whether the aliases need
to be looked up in the local cluster state or in the cluster state held by
the elected master node

[[java-rest-high-get-field-mappings-sync]]
==== Synchronous Execution

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-execute]
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[[java-rest-high-get-field-mapping-async]]
==== Asynchronous Execution

The asynchronous execution of a get mappings request requires both the
`GetFieldMappingsRequest` instance and an `ActionListener` instance to be passed to
the asynchronous method:

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-execute-async]
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<1> The `GetFieldMappingsRequest` 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 `GetMappingsResponse` looks like:

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-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-field-mapping-response]]
==== Get Field Mappings Response

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

["source","java",subs="attributes,callouts,macros"]
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include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[get-field-mapping-response]
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<1> Returning all requested indices fields' mappings
<2> Retrieving the mappings for a particular index and type
<3> Getting the mappings metadata for the `message` field
<4> Getting the full name of the field
<5> Getting the mapping source of the field