@Target(value={METHOD,TYPE})
@Retention(value=RUNTIME)
public @interface Prefix

Indicates the prefix to use when the token written by PlaceTokenizer.getToken(Place) is written to History.newItem(java.lang.String). com.google.gwt.place.rebind.PlaceHistoryMapperGenerator looks for this annotation on the factory methods that return a tokenizer, and on the tokenizer types themselves.