/*

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

 */

#ifndef ATTRIBUTELIST_HPP

#define ATTRIBUTELIST_HPP

#include <xercesc/util/XercesDefs.hpp>

XERCES_CPP_NAMESPACE_BEGIN

/**

  * Interface for an element's attribute specifications.

  *

  * The SAX parser implements this interface and passes an instance

  * to the SAX application as the second argument of each startElement

  * event.

  *

  * The instance provided will return valid results only during the

  * scope of the startElement invocation (to save it for future

  * use, the application must make a copy: the AttributeListImpl

  * helper class provides a convenient constructor for doing so).

  *

  * An AttributeList includes only attributes that have been

  * specified or defaulted: #IMPLIED attributes will not be included.

  *

  * There are two ways for the SAX application to obtain information

  * from the AttributeList.  First, it can iterate through the entire

  * list:

  *

  * <code>

  * public void startElement (String name, AttributeList atts) {<br>

  * &nbsp;for (int i = 0; i < atts.getLength(); i++) {<br>

  * &nbsp;&nbsp;String name = atts.getName(i);<br>

  * &nbsp;&nbsp;String type = atts.getType(i);<br>

  * &nbsp;&nbsp;String value = atts.getValue(i);<br>

  * &nbsp;&nbsp;[...]<br>

  * &nbsp;}<br>

  * }

  * </code>

  *

  * (Note that the result of getLength() will be zero if there

  * are no attributes.)

  *

  * As an alternative, the application can request the value or

  * type of specific attributes:

  *

  * <code>

  * public void startElement (String name, AttributeList atts) {<br>

  * &nbsp;String identifier = atts.getValue("id");<br>

  * &nbsp;String label = atts.getValue("label");<br>

  * &nbsp;[...]<br>

  * }

  * </code>

  *

  * The AttributeListImpl helper class provides a convenience

  * implementation for use by parser or application writers.

  *

  * @see DocumentHandler#startElement

  * @see AttributeListImpl#AttributeListImpl

  */

class SAX_EXPORT AttributeList

{

public:

    // -----------------------------------------------------------------------

    //  Constructors and Destructor

    // -----------------------------------------------------------------------

    /** @name Constructors and Destructor */

    //@{

    /** Default constructor */

    AttributeList()

    {

    }

    /** Destructor */

    virtual ~AttributeList()

    {

    }

    //@}

    /** @name The virtual attribute list interface */

    //@{

  /**

    * Return the number of attributes in this list.

    *

    * The SAX parser may provide attributes in any

    * arbitrary order, regardless of the order in which they were

    * declared or specified.  The number of attributes may be

    * zero.

    *

    * @return The number of attributes in the list.

    */

    virtual unsigned int getLength() const = 0;

  /**

    * Return the name of an attribute in this list (by position).

    *

    * The names must be unique: the SAX parser shall not include the

    * same attribute twice.  Attributes without values (those declared

    * #IMPLIED without a value specified in the start tag) will be

    * omitted from the list.

    *

    * If the attribute name has a namespace prefix, the prefix

    * will still be attached.

    *

    * @param index The index of the attribute in the list (starting at 0).

    * @return The name of the indexed attribute, or null

    *         if the index is out of range.

    * @see #getLength

    */

    virtual const XMLCh* getName(const unsigned int index) const = 0;

  /**

    * Return the type of an attribute in the list (by position).

    *

    * The attribute type is one of the strings "CDATA", "ID",

    * "IDREF", "IDREFS", "NMTOKEN", "NMTOKENS", "ENTITY", "ENTITIES",

    * or "NOTATION" (always in upper case).

    *

    * If the parser has not read a declaration for the attribute,

    * or if the parser does not report attribute types, then it must

    * return the value "CDATA" as stated in the XML 1.0 Recommentation

    * (clause 3.3.3, "Attribute-Value Normalization").

    *

    * For an enumerated attribute that is not a notation, the

    * parser will report the type as "NMTOKEN".

    *

    * @param index The index of the attribute in the list (starting at 0).

    * @return The attribute type as a string, or

    *         null if the index is out of range.

    * @see #getLength

    * @see #getType(String)

    */

    virtual const XMLCh* getType(const unsigned int index) const = 0;

  /**

    * Return the value of an attribute in the list (by position).

    *

    * If the attribute value is a list of tokens (IDREFS,

    * ENTITIES, or NMTOKENS), the tokens will be concatenated

    * into a single string separated by whitespace.

    *

    * @param index The index of the attribute in the list (starting at 0).

    * @return The attribute value as a string, or

    *         null if the index is out of range.

    * @see #getLength

    * @see #getValue(XMLCh*)

    * @see #getValue(char *)

    */

    virtual const XMLCh* getValue(const unsigned int index) const = 0;

  /**

    * Return the type of an attribute in the list (by name).

    *

    * The return value is the same as the return value for

    * getType(int).

    *

    * If the attribute name has a namespace prefix in the document,

    * the application must include the prefix here.

    *

    * @param name The name of the attribute.

    * @return The attribute type as a string, or null if no

    *         such attribute exists.

    * @see #getType(int)

    */

    virtual const XMLCh* getType(const XMLCh* const name) const = 0;

  /**

    * Return the value of an attribute in the list (by name).

    *

    * The return value is the same as the return value for

    * getValue(int).

    *

    * If the attribute name has a namespace prefix in the document,

    * the application must include the prefix here.

    *

    * @param name The name of the attribute in the list.

    * @return The attribute value as a string, or null if

    *         no such attribute exists.

    * @see #getValue(int)

    * @see #getValue(char *)

    */

    virtual const XMLCh* getValue(const XMLCh* const name) const = 0;

  /**

    * Return the value of an attribute in the list (by name).

    *

    * The return value is the same as the return value for

    * getValue(int).

    *

    * If the attribute name has a namespace prefix in the document,

    * the application must include the prefix here.

    *

    * @param name The name of the attribute in the list.

    * @return The attribute value as a string, or null if

    *         no such attribute exists.

    * @see #getValue(int)

    * @see #getValue(XMLCh*)

    */

    virtual const XMLCh* getValue(const char* const name) const = 0;

    //@}

private :

    /* Constructors and operators */

    /* Copy constructor */

    AttributeList(const AttributeList&);

    /* Assignment operator */

    AttributeList& operator=(const AttributeList&);

};

XERCES_CPP_NAMESPACE_END

#endif