Request selectors are referenced by the TestSet of a SubprocessPool to determine if an Sous-processus Arbortext PE pool should service a request. They can be grouped by And and Or elements within a TestSet to set up more complex acceptance criteria.

Individual Request Selectors are invoked when a Sous-processus Arbortext PE pool evaluates a call to its testRequest method to determine whether its Sous-processus Arbortext PE should be allocated to a particular HTTP request. testRequest is normally called by the Arbortext Publishing Engine Request Context as part of evaluating its allocateE3Subprocess method.