For data Structures how would implement this method using Nodes instead of an int array?

/* Find if a key is present in the set. Returns true if the key is present, otherwise false.*/ public boolean find(int key) { // binary search int low = 0, high = size-1; while (low <= high) { int mid = (low + high) / 2; if (set[mid] == key) return true; if (key > set[mid]) low = mid + 1; else high = mid - 1; } return false; }