attributesimpl.java

Default implementation of the Attributes interface

package org.xml.sax.helpers;

import org.xml.sax.Attributes;


/**
 * Default implementation of the Attributes interface.
 *
 * <blockquote>
 * <em>This module, both source code and documentation, is in the
 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
 * </blockquote>
 *
 * <p>This class provides a default implementation of the SAX2
 * {@link org.xml.sax.Attributes Attributes} interface, with the
 * addition of manipulators so that the list can be modified or
 * reused.</p>
 *
 * <p>There are two typical uses of this class:</p>
 *
 * <ol>
 * <li>to take a persistent snapshot of an Attributes object
 *  in a {@link org.xml.sax.ContentHandler#startElement startElement} event; or</li>
 * <li>to construct or modify an Attributes object in a SAX2 driver or filter.</li>
 * </ol>
 *
 * <p>This class replaces the now-deprecated SAX1 {@link
 * org.xml.sax.helpers.AttributeListImpl AttributeListImpl}
 * class; in addition to supporting the updated Attributes
 * interface rather than the deprecated {@link org.xml.sax.AttributeList
 * AttributeList} interface, it also includes a much more efficient
 * implementation using a single array rather than a set of Vectors.</p>

 */
public class AttributesImpl implements Attributes
{


    ////////////////////////////////////////////////////////////////////
    // Constructors.
    ////////////////////////////////////////////////////////////////////


    /**
     * Construct a new, empty AttributesImpl object.
     */
    public AttributesImpl ()
    {
	length = 0;
	data = null;
    }


    /**
     * Copy an existing Attributes object.
     *
     * <p>This constructor is especially useful inside a
     * {@link org.xml.sax.ContentHandler#startElement startElement} event.</p>
     *
     * @param atts The existing Attributes object.
     */
    public AttributesImpl (Attributes atts)
    {
	setAttributes(atts);
    }



    ////////////////////////////////////////////////////////////////////
    // Implementation of org.xml.sax.Attributes.
    ////////////////////////////////////////////////////////////////////


    /**
     * Return the number of attributes in the list.
     *
     * @return The number of attributes in the list.
     * @see org.xml.sax.Attributes#getLength
     */
    public int getLength ()
    {
	return length;
    }


    /**
     * Return an attribute's Namespace URI.
     *
     * @param index The attribute's index (zero-based).
     * @return The Namespace URI, the empty string if none is
     *         available, or null if the index is out of range.
     * @see org.xml.sax.Attributes#getURI
     */
    public String getURI (int index)
    {
	if (index >= 0 && index < length) {
	    return data[index*5];
	} else {
	    return null;
	}
    }


    /**
     * Return an attribute's local name.
     *
     * @param index The attribute's index (zero-based).
     * @return The attribute's local name, the empty string if
     *         none is available, or null if the index if out of range.
     * @see org.xml.sax.Attributes#getLocalName
     */
    public String getLocalName (int index)
    {
	if (index >= 0 && index < length) {
	    return data[index*5+1];
	} else {
	    return null;
	}
    }


    /**
     * Return an attribute's qualified (prefixed) name.
     *
     * @param index The attribute's index (zero-based).
     * @return The attribute's qualified name, the empty string if
     *         none is available, or null if the index is out of bounds.
     * @see org.xml.sax.Attributes#getQName
     */
    public String getQName (int index)
    {
	if (index >= 0 && index < length) {
	    return data[index*5+2];
	} else {
	    return null;
	}
    }


    /**
     * Return an attribute's type by index.
     *
     * @param index The attribute's index (zero-based).
     * @return The attribute's type, "CDATA" if the type is unknown, or null
     *         if the index is out of bounds.
     * @see org.xml.sax.Attributes#getType(int)
     */
    public String getType (int index)
    {
	if (index >= 0 && index < length) {
	    return data[index*5+3];
	} else {
	    return null;
	}
    }


    /**
     * Return an attribute's value by index.
     *
     * @param index The attribute's index (zero-based).
     * @return The attribute's value or null if the index is out of bounds.
     * @see org.xml.sax.Attributes#getValue(int)
     */
    public String getValue (int index)
    {
	if (index >= 0 && index < length) {
	    return data[index*5+4];
	} else {
	    return null;
	}
    }


    /**
     * Look up an attribute's index by Namespace name.
     *
     * <p>In many cases, it will be more efficient to look up the name once and
     * use the index query methods rather than using the name query methods
     * repeatedly.</p>
     *
     * @param uri The attribute's Namespace URI, or the empty
     *        string if none is available.
     * @param localName The attribute's local name.
     * @return The attribute's index, or -1 if none matches.
     * @see org.xml.sax.Attributes#getIndex(java.lang.String,java.lang.String)
     */
    public int getIndex (String uri, String localName)
    {
	int max = length * 5;
	for (int i = 0; i < max; i += 5) {
	    if (data[i].equals(uri) && data[i+1].equals(localName)) {
		return i / 5;
	    }
	}
	return -1;
    }


    /**
     * Look up an attribute's index by qualified (prefixed) name.
     *
     * @param qName The qualified name.
     * @return The attribute's index, or -1 if none matches.
     * @see org.xml.sax.Attributes#getIndex(java.lang.String)
     */
    public int getIndex (String qName)
    {
	int max = length * 5;
	for (int i = 0; i < max; i += 5) {
	    if (data[i+2].equals(qName)) {
		return i / 5;
	    }
	}
	return -1;
    }


    /**
     * Look up an attribute's type by Namespace-qualified name.
     *
     * @param uri The Namespace URI, or the empty string for a name
     *        with no explicit Namespace URI.
     * @param localName The local name.
     * @return The attribute's type, or null if there is no
     *         matching attribute.
     * @see org.xml.sax.Attributes#getType(java.lang.String,java.lang.String)
     */
    public String getType (String uri, String localName)
    {
	int max = length * 5;
	for (int i = 0; i < max; i += 5) {
	    if (data[i].equals(uri) && data[i+1].equals(localName)) {
		return data[i+3];
	    }
	}
	return null;
    }


    /**
     * Look up an attribute's type by qualified (prefixed) name.
     *
     * @param qName The qualified name.
     * @return The attribute's type, or null if there is no
     *         matching attribute.
     * @see org.xml.sax.Attributes#getType(java.lang.String)
     */
    public String getType (String qName)
    {
	int max = length * 5;
	for (int i = 0; i < max; i += 5) {
	    if (data[i+2].equals(qName)) {
		return data[i+3];
	    }
	}
	return null;
    }


    /**
     * Look up an attribute's value by Namespace-qualified name.
     *
     * @param uri The Namespace URI, or the empty string for a name
     *        with no explicit Namespace URI.
     * @param localName The local name.
     * @return The attribute's value, or null if there is no
     *         matching attribute.
     * @see org.xml.sax.Attributes#getValue(java.lang.String,java.lang.String)
     */
    public String getValue (String uri, String localName)
    {
	int max = length * 5;
	for (int i = 0; i < max; i += 5) {
	    if (data[i].equals(uri) && data[i+1].equals(localName)) {
		return data[i+4];
	    }
	}
	return null;
    }


    /**
     * Look up an attribute's value by qualified (prefixed) name.
     *
     * @param qName The qualified name.
     * @return The attribute's value, or null if there is no
     *         matching attribute.
     * @see org.xml.sax.Attributes#getValue(java.lang.String)
     */
    public String getValue (String qName)
    {
	int max = length * 5;
	for (int i = 0; i < max; i += 5) {
	    if (data[i+2].equals(qName)) {