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regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

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////


== session



=== Purpose


The link:{servletApiRefFromRef}session.html[session] object is an instance of the Servlet API's {jakartaee}jakarta/servlet/http/HttpSession.html[HttpSession] class


=== Examples


[source,groovy]
----
class ExampleTagLib {

     def oncePerSession = { Map attrs, body ->
        def key = (attrs.key ?: 'default').toString()
        def sessionKey = "taglib.oncePerSession.${key}"

        if (!session.getAttribute(sessionKey)) {
            session.setAttribute(sessionKey, true)
            out << body()
        }
    }
}
----

[source,xml]
----
<g:oncePerSession key="promo">
    <div class="promo">Free shipping this week!</div>
</g:oncePerSession>
----


=== Description


The {jakartaee}jakarta/servlet/http/HttpSession.html[HttpSession] class is useful for associated session data with a client.

NOTE: The additional methods added to the link:{servletApiRefFromRef}session.html[session] object are documented in the Grails Servlet API reference guide
