Illegal forward reference and enums

problem ：

I'm programming a game in java which is made up of a grid of tiles. I'm using Java Write a game composed of tile grid .I wan't to be able to inuitively define the edges of the tiles and how they relate to each other, eg to get the opposite edge of a tile, I want to be able to just type TOP.opposite() . I don't want to be able to visually define the edges of tiles and how they relate to each other , for example , To obtain the opposite edges of the tiles , I want to be able to enter only TOP.opposite() .However, when using enums to define these edges I end up having to forward reference at least two of them in the contstructor: however , When enumerations are used to define these edges , I finally had to forward reference at least two of them in the constructor ：

public enum Edge {   TOP(Edge.BOTTOM), //illegal forward reference   BOTTOM(Edge.TOP),   LEFT(Edge.RIGHT), //illegal forward reference   RIGHT(Edge.LEFT);   private Edge opposite;   private Edge(Edge opp){      this.opposite = opp;   }   public Edge opposite(){      return this.opposite;   }}

Is there any way of getting round this problem using enums which is just as simple? Is there any way to solve this problem by using the same simple enumeration ？

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Solution ：

Reference resources ： https://stackoom.com/en/question/NpBd