propertylist/FallbackPropertylist.java

   1 /*
   2
   3     special type of propertylist, which has calls an fallback
   4     if some key cannot be found.
   5
   6     this is ie useful to build up derivation hierachies
   7
   8 */
   9
  10 package org.de.metux.propertylist;
  11
  12 import java.util.Properties;
  13
  14 public class FallbackPropertylist extends Propertylist
  15 {
  16     IPropertylist fallback;
  17
  18     public FallbackPropertylist(Properties p)
  19     {
  20         super();
  21         loadHash_top(p);
  22     }
  23
  24     public FallbackPropertylist(IPropertylist f)
  25     {
  26         fallback = f;
  27     }
  28
  29     public String get_raw(String key)
  30         throws EIllegalValue
  31     {
  32         String value = super.get_raw(key);
  33 //      System.err.println("FallbackPropertylist::get_raw(\""+key+"\") => \""+value+"\"");
  34
  35         if (value!=null)
  36             return value;
  37
  38         // we have no fallbacks ... jump out
  39         if (fallback==null)
  40             return null;
  41
  42 //      for (int x=0; x<fallback.length; x++)
  43 //      {
  44 //          if (fallback[x]!=null)
  45 //          {
  46 ///             value = fallback[x].get_raw(key);
  47 //              if (value!=null)
  48 //                  return value;
  49 //          }
  50 //      }
  51         return fallback.get_raw(key);
  52
  53 //      return null;
  54     }
  55
  56     public void setFallback(IPropertylist f)
  57     {
  58 //      fallback = new IPropertylist[1];
  59 //      fallback[0] = f;
  60         fallback = f;
  61     }
  62
  63     public String toString()
  64     {
  65         return "[PRIMARY]\n"+super.toString()+
  66             ((fallback==null) ? "" : "[FALLBACK]\n"+fallback.toString());
  67     }
  68
  69     public IPropertylist clone()
  70     {
  71 //      System.err.println("FallbackPropertylist::clone()");
  72 //      return new FallbackPropertylist(fallback[0]);
  73         return new FallbackPropertylist(fallback);
  74     }
  75 }