Source code: org/outerj/pollo/xmleditor/displayspec/ChainedDisplaySpecification.java

   package org.outerj.pollo.xmleditor.displayspec;
   
   import org.w3c.dom.Element;
   
   import java.awt.*;
   import java.util.ArrayList;
   
   /**
    * A wrapper class around a display specification that allows chaining it.
   * The way chaining works is that if the current instance returns null,
   * the next instance is consulted for a value. Note that the methods in
   * IDisplaySpecification are supposed to always return a value, so make
   * sure that on the end of the chain there's a display specification that
   * always return something for each method.
   *
   * @author Bruno Dumon
   */
  public class ChainedDisplaySpecification implements IDisplaySpecification
  {
      protected ArrayList displaySpecs = new ArrayList();
  
      public void add(IDisplaySpecification displaySpec)
      {
          displaySpecs.add(displaySpec);
      }
  
      public Color getBackgroundColor()
      {
          for (int i = 0; i < displaySpecs.size(); i++)
          {
              Color result = ((IDisplaySpecification)displaySpecs.get(i)).getBackgroundColor();
              if (result != null)
                  return result;
          }
          return null;
      }
  
      public ElementSpec getElementSpec(String namespaceURI, String localName, Element parent)
      {
          for (int i = 0; i < displaySpecs.size(); i++)
          {
              ElementSpec result = ((IDisplaySpecification)displaySpecs.get(i))
                  .getElementSpec(namespaceURI, localName, parent);
              if (result != null)
                  return result;
          }
          return null;
      }
  
      public ElementSpec getElementSpec(Element element)
      {
          for (int i = 0; i < displaySpecs.size(); i++)
          {
              ElementSpec result = ((IDisplaySpecification)displaySpecs.get(i))
                  .getElementSpec(element);
              if (result != null)
                  return result;
          }
          return null;
      }
  
      public int getTreeType()
      {
          for (int i = 0; i < displaySpecs.size(); i++)
          {
              int result = ((IDisplaySpecification)displaySpecs.get(i)).getTreeType();
              if (result != -1)
                  return result;
          }
          return IDisplaySpecification.POLLO_TREE;
      }
  }