/*

 * 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.

 */

/*

 * $Id: DOM_Attr.hpp 568078 2007-08-21 11:43:25Z amassari $

 */

#ifndef DOM_Attr_HEADER_GUARD_

#define DOM_Attr_HEADER_GUARD_

#include <xercesc/util/XercesDefs.hpp>

#include "DOM_Node.hpp"

#include "DOM_Element.hpp"

XERCES_CPP_NAMESPACE_BEGIN

class AttrImpl;

/**

* The <code>DOM_Attr</code> class refers to an attribute of an XML element.

*

* Typically the allowable values for the

* attribute are defined in a documenttype definition.

* <p><code>DOM_Attr</code> objects inherit the <code>DOM_Node</code>  interface, but

* since attributes are not actually child nodes of the elements they are associated with, the

* DOM does not consider them part of the document  tree.  Thus, the

* <code>DOM_Node</code> attributes <code>parentNode</code>,

* <code>previousSibling</code>, and <code>nextSibling</code> have a  null

* value for <code>DOM_Attr</code> objects. The DOM takes the  view that

* attributes are properties of elements rather than having a  separate

* identity from the elements they are associated with;  this should make it

* more efficient to implement such features as default attributes associated

* with all elements of a  given type.  Furthermore, attribute nodes

* may not be immediate children of a <code>DocumentFragment</code>. However,

* they can be associated with <code>Element</code> nodes contained within a

* <code>DocumentFragment</code>. In short, users of the DOM

* need to be aware that  <code>Attr</code> nodes have some things in  common

* with other objects inheriting the <code>Node</code> interface, but they

* also are quite distinct.

*

*/

class DEPRECATED_DOM_EXPORT DOM_Attr: public DOM_Node {

public:

  /** @name Constructors and assignment operators */

  //@{

  /**

    * Default constructor for DOM_Attr.  The resulting object does not

    * refer to any Attribute; it will compare == to 0, and is similar

    * to a null object reference variable in Java.

    *

    */

    DOM_Attr();

public:

  /**

    * Copy constructor.  Creates a new <code>DOM_Attr</code> that refers to the

    *   same underlying Attribute as the original.  See also DOM_Node::clone(),

    * which will copy an actual attribute, rather than just creating a new

    * reference to the original attribute.

    *

    * @param other The source attribute reference object

    */

    DOM_Attr(const DOM_Attr &other);

  /**

    * Assignment operator

    *

    * @param other The source attribute object

    */

    DOM_Attr & operator = (const DOM_Attr &other);

    /**

      * Assignment operator.  This overloaded variant is provided for

      *   the sole purpose of setting a DOM_Node reference variable to

      *   zero.  Nulling out a reference variable in this way will decrement

      *   the reference count on the underlying Node object that the variable

      *   formerly referenced.  This effect is normally obtained when reference

      *   variable goes out of scope, but zeroing them can be useful for

      *   global instances, or for local instances that will remain in scope

      *   for an extended time,  when the storage belonging to the underlying

      *   node needs to be reclaimed.

      *

      * @param val   Only a value of 0, or null, is allowed.

      */

    DOM_Attr & operator = (const DOM_NullPtr *val);

	//@}

  /** @name Destructor */

  //@{

  /**

    * Destructor.  The object being destroyed is a reference to the Attribute

    * "node", not the underlying attribute itself.

    *

    */

    ~DOM_Attr();

	//@}

  /** @name Getter functions */

  //@{

    /**

    * Returns the name of this attribute.

    */

    DOMString       getName() const;

    /**

    *

    * Returns true if the attribute received its value explicitly in the

    * XML document, or if a value was assigned programatically with

    * the setValue function.  Returns false if the attribute value

    * came from the default value declared in the document's DTD.

    */

    bool            getSpecified() const;

    /**

	* Returns the value of the attribute.

	*

    * The value of the attribute is returned as a string.

    * Character and general entity references are replaced with their values.

    */

    DOMString       getValue() const;

	//@}

  /** @name Setter functions */

  //@{

    /**

	* Sets the value of the attribute.  A text node with the unparsed contents

    * of the string will be created.

	*

    * @param value The value of the DOM attribute to be set

    */

    void            setValue(const DOMString &value);

	//@}

    /** @name Functions introduced in DOM Level 2. */

    //@{

    /**

     * The <code>DOM_Element</code> node this attribute is attached to or

     * <code>null</code> if this attribute is not in use.

     *

     */

    DOM_Element     getOwnerElement() const;

    //@}

protected:

    DOM_Attr(AttrImpl *attr);

    friend class DOM_Element;

    friend class DOM_Document;

};

XERCES_CPP_NAMESPACE_END

#endif