/*

 * Copyright (c) 2000, 2005, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

// SAX default implementation for AttributeList.

// http://www.saxproject.org

// No warranty; no copyright -- use this as you will.

// $Id: AttributeListImpl.java,v 1.2 2004/11/03 22:53:08 jsuttor Exp $

package org.xml.sax.helpers;

import org.xml.sax.AttributeList;

import java.util.Vector;

/**

 * Default implementation for AttributeList.

 *

 * <blockquote>

 * <em>This module, both source code and documentation, is in the

 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>

 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>

 * for further information.

 * </blockquote>

 *

 * <p>AttributeList implements the deprecated SAX1 {@link

 * org.xml.sax.AttributeList AttributeList} interface, and has been

 * replaced by the new SAX2 {@link org.xml.sax.helpers.AttributesImpl

 * AttributesImpl} interface.</p>

 *

 * <p>This class provides a convenience implementation of the SAX

 * {@link org.xml.sax.AttributeList AttributeList} interface.  This

 * implementation is useful both for SAX parser writers, who can use

 * it to provide attributes to the application, and for SAX application

 * writers, who can use it to create a persistent copy of an element's

 * attribute specifications:</p>

 *

 * <pre>

 * private AttributeList myatts;

 *

 * public void startElement (String name, AttributeList atts)

 * {

 *              // create a persistent copy of the attribute list

 *              // for use outside this method

 *   myatts = new AttributeListImpl(atts);

 *   [...]

 * }

 * </pre>

 *

 * <p>Please note that SAX parsers are not required to use this

 * class to provide an implementation of AttributeList; it is

 * supplied only as an optional convenience.  In particular,

 * parser writers are encouraged to invent more efficient

 * implementations.</p>

 *

 * @deprecated This class implements a deprecated interface,

 *             {@link org.xml.sax.AttributeList AttributeList};

 *             that interface has been replaced by

 *             {@link org.xml.sax.Attributes Attributes},

 *             which is implemented in the

 *             {@link org.xml.sax.helpers.AttributesImpl

 *            AttributesImpl} helper class.

 * @author David Megginson

 * @see org.xml.sax.AttributeList

 * @see org.xml.sax.DocumentHandler#startElement

 */

public class AttributeListImpl implements AttributeList

{

    /**

     * Create an empty attribute list.

     *

     * <p>This constructor is most useful for parser writers, who

     * will use it to create a single, reusable attribute list that

     * can be reset with the clear method between elements.</p>

     *

     * @see #addAttribute

     * @see #clear

     */

    public AttributeListImpl ()

    {

    }

    /**

     * Construct a persistent copy of an existing attribute list.

     *

     * <p>This constructor is most useful for application writers,

     * who will use it to create a persistent copy of an existing

     * attribute list.</p>

     *

     * @param atts The attribute list to copy

     * @see org.xml.sax.DocumentHandler#startElement

     */

    public AttributeListImpl (AttributeList atts)

    {

        setAttributeList(atts);

    }

    ////////////////////////////////////////////////////////////////////

    // Methods specific to this class.

    ////////////////////////////////////////////////////////////////////

    /**

     * Set the attribute list, discarding previous contents.

     *

     * <p>This method allows an application writer to reuse an

     * attribute list easily.</p>

     *

     * @param atts The attribute list to copy.

     */

    public void setAttributeList (AttributeList atts)

    {

        int count = atts.getLength();

        clear();

        for (int i = 0; i < count; i++) {

            addAttribute(atts.getName(i), atts.getType(i), atts.getValue(i));

        }

    }

    /**

     * Add an attribute to an attribute list.

     *

     * <p>This method is provided for SAX parser writers, to allow them

     * to build up an attribute list incrementally before delivering

     * it to the application.</p>

     *

     * @param name The attribute name.

     * @param type The attribute type ("NMTOKEN" for an enumeration).

     * @param value The attribute value (must not be null).

     * @see #removeAttribute

     * @see org.xml.sax.DocumentHandler#startElement

     */

    public void addAttribute (String name, String type, String value)

    {

        names.addElement(name);

        types.addElement(type);

        values.addElement(value);

    }

    /**

     * Remove an attribute from the list.

     *

     * <p>SAX application writers can use this method to filter an

     * attribute out of an AttributeList.  Note that invoking this

     * method will change the length of the attribute list and

     * some of the attribute's indices.</p>

     *

     * <p>If the requested attribute is not in the list, this is

     * a no-op.</p>

     *

     * @param name The attribute name.

     * @see #addAttribute

     */

    public void removeAttribute (String name)

    {

        int i = names.indexOf(name);

        if (i >= 0) {

            names.removeElementAt(i);

            types.removeElementAt(i);

            values.removeElementAt(i);

        }

    }

    /**

     * Clear the attribute list.

     *

     * <p>SAX parser writers can use this method to reset the attribute

     * list between DocumentHandler.startElement events.  Normally,

     * it will make sense to reuse the same AttributeListImpl object

     * rather than allocating a new one each time.</p>

     *

     * @see org.xml.sax.DocumentHandler#startElement

     */

    public void clear ()

    {

        names.removeAllElements();

        types.removeAllElements();

        values.removeAllElements();

    }

    ////////////////////////////////////////////////////////////////////

    // Implementation of org.xml.sax.AttributeList

    ////////////////////////////////////////////////////////////////////

    /**

     * Return the number of attributes in the list.

     *

     * @return The number of attributes in the list.

     * @see org.xml.sax.AttributeList#getLength

     */

    public int getLength ()

    {

        return names.size();

    }

    /**

     * Get the name of an attribute (by position).

     *

     * @param i The position of the attribute in the list.

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

     *         is no attribute at that position.

     * @see org.xml.sax.AttributeList#getName(int)

     */

    public String getName (int i)

    {

        if (i < 0) {

            return null;

        }

        try {

            return (String)names.elementAt(i);

        } catch (ArrayIndexOutOfBoundsException e) {

            return null;

        }

    }

    /**

     * Get the type of an attribute (by position).

     *

     * @param i The position of the attribute in the list.

     * @return The attribute type as a string ("NMTOKEN" for an

     *         enumeration, and "CDATA" if no declaration was

     *         read), or null if there is no attribute at

     *         that position.

     * @see org.xml.sax.AttributeList#getType(int)

     */

    public String getType (int i)

    {

        if (i < 0) {

            return null;

        }

        try {

            return (String)types.elementAt(i);

        } catch (ArrayIndexOutOfBoundsException e) {

            return null;

        }

    }

    /**

     * Get the value of an attribute (by position).

     *

     * @param i The position of the attribute in the list.

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

     *         there is no attribute at that position.

     * @see org.xml.sax.AttributeList#getValue(int)

     */

    public String getValue (int i)

    {

        if (i < 0) {

            return null;

        }

        try {

            return (String)values.elementAt(i);

        } catch (ArrayIndexOutOfBoundsException e) {

            return null;

        }

    }

    /**

     * Get the type of an attribute (by name).

     *

     * @param name The attribute name.

     * @return The attribute type as a string ("NMTOKEN" for an

     *         enumeration, and "CDATA" if no declaration was

     *         read).

     * @see org.xml.sax.AttributeList#getType(java.lang.String)

     */

    public String getType (String name)

    {

        return getType(names.indexOf(name));

    }

    /**

     * Get the value of an attribute (by name).

     *

     * @param name The attribute name.

     * @see org.xml.sax.AttributeList#getValue(java.lang.String)

     */

    public String getValue (String name)

    {

        return getValue(names.indexOf(name));

    }

    ////////////////////////////////////////////////////////////////////

    // Internal state.

    ////////////////////////////////////////////////////////////////////

    Vector names = new Vector();

    Vector types = new Vector();

    Vector values = new Vector();

}

// end of AttributeListImpl.java