How to use enum with DropDownChoice

Application.properties

# for RockPaperScissors
RockPaperScissors.ROCK=\u30b0\u30fc
RockPaperScissors.PAPER=\u30d1\u30fc
RockPaperScissors.SCISSORS=\u30c1\u30e7\u30ad

RockPaperScissors.java

public enum RockPaperScissors {
    ROCK,PAPER,SCISSORS;
}

RockPaperScissorsDropDownChoice.java

public class RockPaperScissorsDropDownChoice
    extends DropDownChoice<RockPaperScissors> {

    public RockPaperScissorsDropDownChoice(String id) {
	super(id,
	      Arrays.asList(RockPaperScissors.values()),
	      new EnumChoiceRenderer<RockPaperScissors>());
    }
}