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Otherwise the formats specified in an SP's metadata are filtered against a nameIDFormatPrecedence profile configuration property, if set, and the resulting set of Formats is tried in order. That is, the first Format in the profile configuration that is also in the metadata and that results in a valid result will be used.
If metadata is specified but no profile setting is, then the metadata is used as is, and vice versa.
Default Formats for each SAML version are set via saml-nameid.properties and are used in the event that nothing else is called for. You should not alter that setting in most cases.
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