domentityreference.java

gcc的组建

/* DomEntityReference.java -- 
   Copyright (C) 1999,2000,2001,2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */

package gnu.xml.dom;

import org.w3c.dom.DocumentType;
import org.w3c.dom.Entity;
import org.w3c.dom.EntityReference;

/**
 * <p> "EntityReference" implementation (reference to parsed entity).
 * This is a non-core DOM class, supporting the "XML" feature.
 * It does not represent builtin entities (such as "&amp;amp;")
 * or character references, which are always directly expanded in
 * DOM trees.</p>
 *
 * <p> Note that while the DOM specification permits these nodes to have
 * a readonly set of children, this is not required.  Similarly, it does
 * not require a DOM to couple EntityReference nodes with any Entity nodes
 * that have the same entity name (and equivalent children).  It also
 * effectively guarantees that references created directly or indirectly
 * through the <em>Document.ImportNode</em> method will not have children.
 * The level of functionality you may get is extremely variable.
 *
 * <p> Also significant is that even at their most functional level, the fact
 * that EntityReference children must be readonly has caused significant
 * problems when modifying work products held in DOM trees.  Other problems
 * include issues related to undeclared namespace prefixes (and references
 * to the current default namespace) that may be found in the text of such
 * parsed entities nodes.  These must be contextually bound as part of DOM
 * tree construction.  When such nodes are moved, the namespace associated
 * with a given prefix (or default) may change to be in conflict with the
 * namespace bound to the node at creation time.
 *
 * <p> In short, <em>avoid using this DOM functionality</em>.
 *
 * @see DomDoctype
 * @see DomEntity
 *
 * @author David Brownell 
 * @author <a href='mailto:[e-mail]'>Chris Burdess</a>
 */
public class DomEntityReference
  extends DomNode
  implements EntityReference
{

  private String name;
  
  /**
   * Constructs an EntityReference node associated with the specified
   * document.  The creator should populate this with whatever contents
   * are appropriate, and then mark it as readonly.
   *
   * <p>This constructor should only be invoked by a Document as part of
   * its createEntityReference functionality, or through a subclass which
   * is similarly used in a "Sub-DOM" style layer.
   *
   * @see DomNode#makeReadonly
   */
  protected DomEntityReference(DomDocument owner, String name)
  {
    super(ENTITY_REFERENCE_NODE, owner);
    this.name = name;
  }
  
  /**
   * Returns the name of the referenced entity.
   * @since DOM Level 1 Core
   */
  public final String getNodeName()
  {
    return name;
  }

  /**
   * The base URI of an entity reference is the base URI where the entity
   * declaration occurs.
   * @since DOM Level 3 Core
   */
  public final String getBaseURI()
  {
    DocumentType doctype = owner.getDoctype();
    if (doctype == null)
      {
        return null;
      }
    Entity entity = (Entity) doctype.getEntities().getNamedItem(name);
    if (entity == null)
      {
        return null;
      }
    return entity.getBaseURI();
  }

}