attributesimpl.java

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    }



    ////////////////////////////////////////////////////////////////////
    // Manipulators.
    ////////////////////////////////////////////////////////////////////


    /**
     * Clear the attribute list for reuse.
     *
     * <p>Note that little memory is freed by this call:
     * the current array is kept so it can be 
     * reused.</p>
     */
    public void clear ()
    {
	if (data != null) {
	    for (int i = 0; i < (length * 5); i++)
		data [i] = null;
	}
	length = 0;
    }


    /**
     * Copy an entire Attributes object.
     *
     * <p>It may be more efficient to reuse an existing object
     * rather than constantly allocating new ones.</p>
     * 
     * @param atts The attributes to copy.
     */
    public void setAttributes (Attributes atts)
    {
        clear();
        length = atts.getLength();
        if (length > 0) {
            data = new String[length*5];
            for (int i = 0; i < length; i++) {
                data[i*5] = atts.getURI(i);
                data[i*5+1] = atts.getLocalName(i);
                data[i*5+2] = atts.getQName(i);
                data[i*5+3] = atts.getType(i);
                data[i*5+4] = atts.getValue(i);
            }
	}
    }


    /**
     * Add an attribute to the end of the list.
     *
     * <p>For the sake of speed, this method does no checking
     * to see if the attribute is already in the list: that is
     * the responsibility of the application.</p>
     *
     * @param uri The Namespace URI, or the empty string if
     *        none is available or Namespace processing is not
     *        being performed.
     * @param localName The local name, or the empty string if
     *        Namespace processing is not being performed.
     * @param qName The qualified (prefixed) name, or the empty string
     *        if qualified names are not available.
     * @param type The attribute type as a string.
     * @param value The attribute value.
     */
    public void addAttribute (String uri, String localName, String qName,
			      String type, String value)
    {
	ensureCapacity(length+1);
	data[length*5] = uri;
	data[length*5+1] = localName;
	data[length*5+2] = qName;
	data[length*5+3] = type;
	data[length*5+4] = value;
	length++;
    }


    /**
     * Set an attribute in the list.
     *
     * <p>For the sake of speed, this method does no checking
     * for name conflicts or well-formedness: such checks are the
     * responsibility of the application.</p>
     *
     * @param index The index of the attribute (zero-based).
     * @param uri The Namespace URI, or the empty string if
     *        none is available or Namespace processing is not
     *        being performed.
     * @param localName The local name, or the empty string if
     *        Namespace processing is not being performed.
     * @param qName The qualified name, or the empty string
     *        if qualified names are not available.
     * @param type The attribute type as a string.
     * @param value The attribute value.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void setAttribute (int index, String uri, String localName,
			      String qName, String type, String value)
    {
	if (index >= 0 && index < length) {
	    data[index*5] = uri;
	    data[index*5+1] = localName;
	    data[index*5+2] = qName;
	    data[index*5+3] = type;
	    data[index*5+4] = value;
	} else {
	    badIndex(index);
	}
    }


    /**
     * Remove an attribute from the list.
     *
     * @param index The index of the attribute (zero-based).
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void removeAttribute (int index)
    {
	if (index >= 0 && index < length) {
	    if (index < length - 1) {
		System.arraycopy(data, (index+1)*5, data, index*5,
				 (length-index-1)*5);
	    }
	    index = (length - 1) * 5;
	    data [index++] = null;
	    data [index++] = null;
	    data [index++] = null;
	    data [index++] = null;
	    data [index] = null;
	    length--;
	} else {
	    badIndex(index);
	}
    }


    /**
     * Set the Namespace URI of a specific attribute.
     *
     * @param index The index of the attribute (zero-based).
     * @param uri The attribute's Namespace URI, or the empty
     *        string for none.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void setURI (int index, String uri)
    {
	if (index >= 0 && index < length) {
	    data[index*5] = uri;
	} else {
	    badIndex(index);
	}
    }


    /**
     * Set the local name of a specific attribute.
     *
     * @param index The index of the attribute (zero-based).
     * @param localName The attribute's local name, or the empty
     *        string for none.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void setLocalName (int index, String localName)
    {
	if (index >= 0 && index < length) {
	    data[index*5+1] = localName;
	} else {
	    badIndex(index);
	}
    }


    /**
     * Set the qualified name of a specific attribute.
     *
     * @param index The index of the attribute (zero-based).
     * @param qName The attribute's qualified name, or the empty
     *        string for none.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void setQName (int index, String qName)
    {
	if (index >= 0 && index < length) {
	    data[index*5+2] = qName;
	} else {
	    badIndex(index);
	}
    }


    /**
     * Set the type of a specific attribute.
     *
     * @param index The index of the attribute (zero-based).
     * @param type The attribute's type.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void setType (int index, String type)
    {
	if (index >= 0 && index < length) {
	    data[index*5+3] = type;
	} else {
	    badIndex(index);
	}
    }


    /**
     * Set the value of a specific attribute.
     *
     * @param index The index of the attribute (zero-based).
     * @param value The attribute's value.
     * @exception java.lang.ArrayIndexOutOfBoundsException When the
     *            supplied index does not point to an attribute
     *            in the list.
     */
    public void setValue (int index, String value)
    {
	if (index >= 0 && index < length) {
	    data[index*5+4] = value;
	} else {
	    badIndex(index);
	}
    }



    ////////////////////////////////////////////////////////////////////
    // Internal methods.
    ////////////////////////////////////////////////////////////////////


    /**
     * Ensure the internal array's capacity.
     *
     * @param n The minimum number of attributes that the array must
     *        be able to hold.
     */
    private void ensureCapacity (int n)    {
        if (n <= 0) {
            return;
        }
        int max;
        if (data == null || data.length == 0) {
            max = 25;
        }
        else if (data.length >= n * 5) {
            return;
        }
        else {
            max = data.length;
        }
        while (max < n * 5) {
            max *= 2;
        }

        String newData[] = new String[max];
        if (length > 0) {
            System.arraycopy(data, 0, newData, 0, length*5);
        }
        data = newData;
    }


    /**
     * Report a bad array index in a manipulator.
     *
     * @param index The index to report.
     * @exception java.lang.ArrayIndexOutOfBoundsException Always.
     */
    private void badIndex (int index)
	throws ArrayIndexOutOfBoundsException
    {
	String msg =
	    "Attempt to modify attribute at illegal index: " + index;
	throw new ArrayIndexOutOfBoundsException(msg);
    }



    ////////////////////////////////////////////////////////////////////
    // Internal state.
    ////////////////////////////////////////////////////////////////////

    int length;
    String data [];

}

// end of AttributesImpl.java