.. _ParameterDirectives-java:

ParameterDirectives
===================

.. toctree::
   :maxdepth: 1

   parameter
   parameters
   parameterMap
   parameterMultiMap
   parameterSeq

.. _which-parameter-directive-java:

When to use which parameter directive?
--------------------------------------

Usually, you want to use the high-level :ref:`-parameter-java-` directive. When you need
more low-level access you can use the table below to decide which directive
to use which shows properties of different parameter directives.

================================ ====== ======== =====
directive                        level  ordering multi
================================ ====== ======== =====
:ref:`-parameter-java-`          high   no       no
:ref:`-parameterMap-java-`       low    no       no
:ref:`-parameterMultiMap-java-`  low    no       yes
:ref:`-parameterList-java-`      low    yes      yes
================================ ====== ======== =====

level
    high-level parameter directives extract subset of all parameters by name and allow conversions
    and automatically report errors if expectations are not met, low-level directives give you
    all parameters at once, leaving all further processing to you

ordering
    original ordering from request URL is preserved

multi
    multiple values per parameter name are possible

.. note::
  If you need to extract multiple parameters, apply the ``parameter`` directive multiple times.