java.lang.Enum>

public enum Direction {

　　L, LU, U, RU, R, RD, D, LD, STOP, JUMP;

}

for(Direction d: Direction.values()) {

　　this.drawPaoTong(g, d);

}

for (int i = 0; i < Direction.values().length; i++) {

　　Direction.values()[i];

}

枚举随机遍历：Direction.values()[new Random().nextInt(Direction.values().length)];