Prior to JDK 26, in the JDK default implementation of the HTTP server in the `jdk.httpserver module`, the `HttpExchange` attribute map was shared with the enclosing `HttpContext`.

Since JDK 26, by default, context attributes are no longer shared with all of their exchanges. Instead, each exchange has its own map of attributes. This default behavior can be reverted to the pre-JDK 26 behavior by setting the `jdk.httpserver.attributes` system property.

See the [jdk.httpserver] module-info for more information.