Store a list of triplet with constant look up

Question

I would like to store a list of triplets of Enums- say List<<Enum1, Enum2, Enum3>> where I should be able to look up by any of the fields. What I mean is, say I store something like,

List<<Enum1, Enum2, Enum3>> list; 
list[0] = [ObjectOfEnum1, ObjectOfEnum2, ObjectOfEnum3]
list[1] = [ObjectOfEnum4, ObjectOfEnum5, ObjectOfEnum6]
list[2] = [ObjectOfEnum7, ObjectOfEnum8, ObjectOfEnum9]
list[3] = [ObjectOfEnum10, ObjectOfEnum11, ObjectOfEnum12]
.
.

I should be able to look up either by ObjectOfEnum5 to get list[1] or by ObjectOfEnum1 to get list[0]. I would like to get them in O(1). I am working with Java 8. Please point me to any data structure that could help me do this.

I can only think of having three Maps(each having a key of the different types of Enums) with the value of a tuple of the other 2. But this solution looks ugly. Please let me know if there is something I can use.