DelegatingResourceDictionary.java :  » XML » java-axp » javaaxp » core » service » Java Open Source

/*
 * java-axp XPS utility
 * Copyright (C) 2007-2008 Chris Pope
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

package javaaxp.core.service;

import javaaxp.core.service.model.document.IDocumentReference;
import javaaxp.core.service.model.document.page.IPageResource;
import javaaxp.core.service.model.document.page.IPageResourceDictionary;

public class DelegatingResourceDictionary {
  private DelegatingResourceDictionary fParent;
  private IPageResourceDictionary fDict;

  
  public static final DelegatingResourceDictionary EMPTY_RESOURCE_DICTIONARY = new DelegatingResourceDictionary(){
    public Object get(String key) throws XPSSpecError{
      return null;
    }
  };
  
  private DelegatingResourceDictionary() {
    fParent = null;
    fDict = null;
  }
  
  public DelegatingResourceDictionary(DelegatingResourceDictionary parent, IPageResourceDictionary dict, IXPSFileAccess xpsFileAccess, IDocumentReference docRef) throws XPSError{
    fParent = parent;

    if(dict != null){
      if(dict.getSource() != null && dict.getImageBrushOrLinearGradientBrushOrRadialGradientBrush() != null){
        throw new XPSSpecError(7,6,"Resource Dictionary references both external file and own children");
      }
      
      if(dict.getSource() != null){
        //read the resource version
        xpsFileAccess.getResourceDictionary(dict.getSource(), docRef);
      } else {
        fDict = dict;
      }
    }
  }
  
  public Object get(String key) throws XPSSpecError{
    Object ret = localDictionaryLookup(key);
    if(ret == null){
      if(fParent != null){
        return fParent.get(key);
      } else {
        throw new XPSSpecError(7,1,"Resource named " + key + " not found in page dictionary");
      }
    } else {
      return ret;
    }
  }

  private Object localDictionaryLookup(String key) {
    for (IPageResource pr : fDict.getImageBrushOrLinearGradientBrushOrRadialGradientBrush()) {
      if(pr.getKey().equals(key)){
        return pr;
      }
    }
    return null;
  }
  
  public DelegatingResourceDictionary getParent() {
    return fParent;
  }

}