code: public static boolean isAssignableFrom(MappedField destination,MappedField source)  {
  		return isAssignableFrom(destination.getValue(), source.getValue());
  	}
docs: this method verify that the instruction:
  <p><code> destination = source </code>
  <p>is permitted, checking their generics also
  
  @param destination of type {@link MappedField}
  @param source of type {@link MappedField}
  @return true if destination is assignable from source