code: @Override
  	public final boolean propertyExists(String name)
      {
          if (name == null || name.length() == 0)
              throw new IllegalArgumentException("Empty property name");
          
          assertDeserializationLevel(MessageSerializationLevel.ALL_HEADERS);
          return propertyMap != null ? propertyMap.containsKey(name) : false;
      }
docs: /* (non-Javadoc)
  @see javax.jms.Message#propertyExists(java.lang.String)