Summary

The apidoc and impl for HttpExchange.get/setAttributes is not clear on whether the attribute map is per exchange or per context.

Problem

The apidoc and impl for HttpExchange.get/setAttributes is not clear on whether the attribute map is per exchange or per context. Some implementations treat them as per exchange, whereas the default JDK impl treats them as per context. It is more useful to treat them as per exchange since the per context attributes are separately available through HttpContext.getAttributes.

This is a behavior change though, so it is proposed to add a system property to restore the old behavior.

Solution

As outlined above

Specification

No API change, but the behavior change is documented in the following addition to the jdk.httpserver module-info

* @implNote
 * Prior to JDK 26, in the JDK default implementation, the {@link HttpExchange} attribute map was
 * shared with the enclosing {@link HttpContext}.
 * Since JDK 26, by default, exchange attributes are per-exchange and the context attributes must
 * be accessed by calling {@link HttpExchange#getHttpContext() getHttpContext()}{@link
 * HttpContext#getAttributes() .getAttributes()}. <br>
 * A new system property, <b>{@systemProperty jdk.httpserver.attributes}</b> (default value: {@code ""})
 * allows to revert this new behavior. Set this property to "context" to restore the pre JDK 26 behavior.