The problem here is that the hashCode of an array does not depend on the contents, but on the reference. That means that if you have two conjunction / disjunction keys that are equal, but the contained arrays are not the same objects, then the hashcode of the keys will be different.
The solution that probably takes the least effort is replacing the arrays with ArrayLists, which do base their hashCode on the content.
0
solved HashMap key generation based on hashing