package org.opengroupware.jope.eocontrol;

import org.opengroupware.jope.foundation.NSKeyValueCoding;

public interface EOKeyValueCoding {

  public void takeStoredValueForKey(Object _value, String _key);
  public Object storedValueForKey(String _key);

  /* utility class (use those methods to query objects with KVC) */

  public class Utility {
    
    public void takeStoredValueForKey(Object _o, Object _value, String _key) {
      if (_o == null)
        return;
      
      if (_o instanceof EOKeyValueCoding)
        ((EOKeyValueCoding)_o).takeStoredValueForKey(_value, _key);
      else {
        EOKeyValueCoding.DefaultImplementation
          .takeStoredValueForKey(_o, _value, _key);
      }
    }
    
    public Object storedValueForKey(Object _o, String _k) {
      if (_o == null)
        return null;
      
      if (_o instanceof EOKeyValueCoding)
        return ((EOKeyValueCoding)_o).storedValueForKey(_k);

      return EOKeyValueCoding.DefaultImplementation.storedValueForKey(_o, _k);
    }
    
  }

  /* this can be used by Object subclasses which want to implement
   * NSKeyValueCoding
   */
  public class DefaultImplementation {
    
    public static void takeStoredValueForKey(Object _o, Object _v, String _k) {
      NSKeyValueCoding.DefaultImplementation.takeValueForKey(_o, _v, _k);
    }
    
    public static Object storedValueForKey(Object _o, String _key) {
      return NSKeyValueCoding.DefaultImplementation.valueForKey(_o, _key);
    }    
  }
}