http://xml.apache.org/commons/components/external/: xml-commons provides an Apache-hosted set of DOM, SAX, and JAXP interfaces for use in other xml-based projects. Our hope is that we can standardize on both a common version and packaging scheme for these critical XML standards interfaces to make the lives of both our developers and users easier. The External Components portion of xml-commons contains interfaces that are defined by external standards organizations. For DOM, that's the W3C; for SAX it's David Megginson and sax.sourceforge.net; for JAXP it's Sun. 
/*
 * Copyright (c) 2004 World Wide Web Consortium,
 *
 * (Massachusetts Institute of Technology, European Research Consortium for
 * Informatics and Mathematics, Keio University). All Rights Reserved. This
 * work is distributed under the W3C(r) Software License [1] 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.
 *
 * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
 */

package org.w3c.dom;


DOMLocator is an interface that describes a location (e.g. 
where an error occurred).

See also the Document Object Model (DOM) Level 3 Core Specification.

Since:DOM Level 3
/**
 * <code>DOMLocator</code> is an interface that describes a location (e.g. 
 * where an error occurred).
 * <p>See also the <a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>Document Object Model (DOM) Level 3 Core Specification</a>.
 * @since DOM Level 3
 */
public interface DOMLocator {
    
The line number this locator is pointing to, or -1 if 
there is no column number available.

/**
     * The line number this locator is pointing to, or <code>-1</code> if 
     * there is no column number available.
     */
    public int getLineNumber();

    
The column number this locator is pointing to, or -1 if 
there is no column number available.

/**
     * The column number this locator is pointing to, or <code>-1</code> if 
     * there is no column number available.
     */
    public int getColumnNumber();

    
The byte offset into the input source this locator is pointing to or 
-1 if there is no byte offset available.

/**
     * The byte offset into the input source this locator is pointing to or 
     * <code>-1</code> if there is no byte offset available.
     */
    public int getByteOffset();

    
The UTF-16, as defined in [Unicode] and Amendment 1 of [ISO/IEC 10646], offset into the input source this locator is pointing to or 
-1 if there is no UTF-16 offset available.

/**
     * The UTF-16, as defined in [Unicode] and Amendment 1 of [ISO/IEC 10646], offset into the input source this locator is pointing to or 
     * <code>-1</code> if there is no UTF-16 offset available.
     */
    public int getUtf16Offset();

    
The node this locator is pointing to, or null if no node 
is available.

/**
     * The node this locator is pointing to, or <code>null</code> if no node 
     * is available.
     */
    public Node getRelatedNode();

    
The URI this locator is pointing to, or null if no URI is 
available.

/**
     * The URI this locator is pointing to, or <code>null</code> if no URI is 
     * available.
     */
    public String getUri();

}