xref: /trunk/main/offapi/com/sun/star/configuration/ConfigurationAccess.idl (revision d1766043)

/**************************************************************
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 *************************************************************/


#ifndef __com_sun_star_configuration_ConfigurationAccess_idl__
#define __com_sun_star_configuration_ConfigurationAccess_idl__

#ifndef __com_sun_star_configuration_HierarchyAccess_idl__
#include <com/sun/star/configuration/HierarchyAccess.idl>
#endif

#ifndef __com_sun_star_configuration_HierarchyElement_idl__
#include <com/sun/star/configuration/HierarchyElement.idl>
#endif

#ifndef __com_sun_star_configuration_SetAccess_idl__
#include <com/sun/star/configuration/SetAccess.idl>
#endif

#ifndef __com_sun_star_configuration_GroupAccess_idl__
#include <com/sun/star/configuration/GroupAccess.idl>
#endif

#ifndef __com_sun_star_configuration_AccessRootElement_idl__
#include <com/sun/star/configuration/AccessRootElement.idl>
#endif

#ifndef __com_sun_star_configuration_SetElement_idl__
#include <com/sun/star/configuration/SetElement.idl>
#endif

#ifndef __com_sun_star_configuration_GroupElement_idl__
#include <com/sun/star/configuration/GroupElement.idl>
#endif

//=============================================================================

module com { module sun { module star { module configuration {

//=============================================================================
/** provides read access to a fragment of the configuration hierarchy.

 <p>Values that are direct or indirect descendants of a root element can be
 retrieved and, if themselves objects, navigated. Other interfaces provide
 access to information about this element and its context.
 Changes to values in the hierarchy can be monitored by event listeners.
 </p>

 <p>Descendants of this service also implement this service.
 </p>

 <p>Ultimately the configuration holds values. These values are organized into
 a hierarchy using structural elements. The structure is defined in advance in
 a schema. Necessary information from the schema is stored in the configuration
 repository itself and is accessible through an implementation of this service.
 </p>

 <p>Two different kinds of structural elements are used in the configuration
 hierarchy:
 </p>
 <dl>
	<dt>Sets</dt>
		<dd>are dynamic containers of homogeneous elements. Which elements
		a <em>set</em> contains can vary. Their names are defined by the
		clients that insert them. On the other hand, the <em>type</em> of
		the elements is the same for all elements. In the case of elements
		that are themselves hierarchy objects, the <em>type</em> includes
		the structure of the hierarchy fragment they contain. Such types
		are defined in the configuration schema as <em>templates</em>.
		</dd>

	<dt>Groups</dt>
		<dd>are static collections of heterogeneous elements. The names and
		types of the elements of a <em>group</em> are completely defined in the
		configuration schema. Here each element may be of a different
		<em>type</em>, allowing <em>groups</em> that contain a mix of
		subobjects and simple values.
		</dd>
 </dl>

 <p>Objects in the configuration hierarchy, for example, implementations of this service,
 can thus be classified in the following ways:
 </p>
 <ul>
	<li><em>Container</em> role:
		An object that can hold child elements as a <em>set</em> or a <em>group</em>.
	</li>
	<li><em>Element</em> role:
		An object may be an element of a <em>set</em> or a <em>group</em>
		or else it may be the root element.
	</li>
 </ul>

 <p>Several types of simple <em>values</em> can be used in the configuration.
 In addition to the basic (scalar) types, sequences of the basic types are
 supported. The basic types are:
 </p>

 <ul>
	<li><strong>string</strong> can hold a human-readable text.
		<p>Values are represented as <atom>string</atom>.</p>
		<p>Sequences are represented as <atom dim="[]">string</atom>.</p>
		<p>'<em>human-readable</em>' here excludes non-printing characters
		except for CR, LF and TAB [Unicode code points 9,10,13].
		For binary data, use type <strong>binary</strong> instead.</p>
	</li>
	<li><strong>boolean</strong> can hold the values <TRUE/> or <FALSE/>.
		<p>Values are represented as <atom>boolean</atom>.
		<p>Sequences are represented as <atom dim="[]">boolean</atom>.</p>
	</li>
	<li><strong>short</strong> can hold a 16-bit signed integer.
		<p>Values are represented as <atom>short</atom>.</p>
		<p>Sequences are represented as <atom dim="[]">short</atom>.</p>
	</li>
	<li><strong>int</strong> can hold a 32-bit signed integer.
		<p>Values are represented as <atom>long</atom>.</p>
		<p>Sequences are represented as <atom dim="[]">long</atom>.</p>
	</li>
	<li><strong>long</strong> can hold a 64-bit signed integer.
		<p>Values are represented as <atom>hyper</atom>.</p>
		<p>Sequences are represented as <atom dim="[]">hyper</atom>.</p>
	</li>
	<li><strong>double</strong> can hold a floating point number.
		<p>Values are represented as <atom>double</atom>.</p>
		<p>Sequences are represented as <atom dim="[]">double</atom>.</p>
	</li>
	<li><strong>binary</strong> can hold a sequence of octets.
		<p>Values are represented as <atom dim="[]">byte</atom>.</p>
		<p>Sequences are represented as <atom dim="[][]">byte</atom>.</p>
	</li>
 </ul>

 <p>Within templates an additional type <strong>any</strong> can occur. When
 such a template is used to create a new <type>SetElement</type>, the type
 of the element is initially reported as <atom>any</atom> (having no value).
 When the value of such an element is first set, it will assume the type used.
 </p>

 <p>If the schema marks a value as <em>nullable</em> (which is indicated by
 attribute <const scope="com::sun::star::beans">PropertyAttribute::MAYBEVOID</const> ),
 its contents may be <NULL/>.
 </p>

 <p>The configuration should support explicit access to default values
 (implementing <type scope="com::sun::star::beans">XPropertyState</type>
 and  <type scope="com::sun::star::beans">XPropertyWithState</type>).
 </p>

 @see ConfigurationProvider
	Root instances of this service can be requested from a
	<type>ConfigurationProvider</type>.

 @see ConfigurationUpdateAccess
	an extended service that includes facilities for modifying
	configuration data.
*/
published service ConfigurationAccess
{
	/** provides interfaces to access child and descendent elements.

	 <p>An implementation actually implements a specialization of this service,
	 which depends on its <em>Container</em> role.
	 </p>

	 <p>Implementations shall implement exactly one of:</p>
	 <ul>
		<li><type>SetAccess</type> if this element is a <em>Set</em>.</li>
		<li><type>GroupAccess</type> if this element is a <em>Group</em>.</li>
	 </ul>
	 */
	service HierarchyAccess;

	/** provides interfaces to obtain information about this element and its
	 role and context in the hierarchy.

	 <p>An implementation actually implements a specialization of this service,
	 which depends on its <em>Element</em> role.
	 </p>

	 <p>Implementations shall implement exactly one of:</p>
	 <ul>
		<li><type>AccessRootElement</type> if this element is the
			<em>Root</em> of the whole hierarchy. Objects that can be
			created directly by a <type>ConfigurationProvider</type>
			implement this service.</li>
		<li><type>SetElement</type> if this element may be contained in a
			<em>Set</em>.</li>
		<li><type>GroupElement</type> if this element is a child of a
			<em>Group</em>.</li>
	 </ul>

	 */
	service HierarchyElement;

	/** specializes <type>HierarchyAccess</type>, if this element is a <em>Set</em>.

	 	<p>This is an alternative to <type>GroupAccess</type>.
		</p>
	*/
	[optional] service SetAccess;

	/** specializes <type>HierarchyAccess</type>,
	 if this element is a <em>Group</em>.
	 <p>This is an alternative to <type>SetAccess</type>.
	 </p>
	*/
	[optional] service GroupAccess;

	/** specializes <type>HierarchyElement</type>,
	 if this element is the <em>Root</em> of the whole hierarchy.
	 <p>This is an alternative to <type>SetElement</type>
	 or <type>GroupElement</type>.
	 </p>

	 @see ConfigurationProvider
		Instances obtained from a <type>ConfigurationProvider</type> will
		implement this version of <type>HierarchyElement</type>.
	*/
	[optional] service AccessRootElement;

	/** specializes <type>HierarchyElement</type>,
	 if this element may be contained in a <em>Set</em>.
	 <p>This is an alternative to <type>AccessRootElement</type>
	 or <type>GroupElement</type>.
	 </p>
    */
	[optional] service SetElement;

	/** specializes <type>HierarchyElement</type>,
	 if this element is a child of a <em>Group</em>.
	 <p>This is an alternative to <type>AccessRootElement</type>
	 or <type>SetElement</type>.
	 </p>
*/
	[optional] service GroupElement;
};

//=============================================================================

}; }; }; };

#endif