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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 the profile configuration doesn’t specify anything, then the metadata is used alone.
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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