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Cocoon Core 2.2

RequestParameterExistsAction

Summary

This action simply checks to see if a given request parameter exists.

Basic information

Component typeAction
Cocoon blockcore
Java classorg.apache.cocoon.acting.RequestParameterExistsAction
Name in Sitemap
Cacheable

Documentation

It takes an arbitrary number of default parameters to check
named 'parameter-name'. Non-default parameters need to be separated
by spaces and passed as value of a sitemap parameter named
'parameters'. The action returns a map with all parameters if all
of them exist and null otherwise. Parameter names can only be added
to this list but no default parameters can be overridden by
specific ones.

This action is very closely related to @link{RequestParamAction}
and {@link FormValidatorAction}. However this action is considerably
simpler in that it tests only for existence of a parameter and it
doesn't need a descriptor. Besides it doesn't propagate all request
parameters to the sitemap but only those that are marked as
required.
One special feature is, however, that parameters
can contain one wildcard ("*"). It will be
checked, whether all parameters with a wildcard have the same
matches. E.g. "id_* name_*" enforces, that if "id_1" exists,
"name_1" must also exist and vice versa.