Count Special Triplets

class Solution {
    public int specialTriplets(int[] nums) {
        final int MOD = 1000000007;
        final int n = nums.length;

        HashMap<Integer, Integer> map1 = new HashMap<>();
        for(int num: nums) {
            map1.put(num, map1.getOrDefault(num, 0) + 1);
        }

        HashMap<Integer, Integer> map2 = new HashMap<>();

        long triplets = 0;

        for(int i=0; i<n; i++) {

            map1.put(nums[i], map1.get(nums[i]) - 1);

            long leftFreq = map2.getOrDefault(nums[i] * 2, 0);
            long rightFreq = map1.getOrDefault(nums[i] * 2, 0);

            long currTriplets = (leftFreq * rightFreq) % MOD;
            triplets = (triplets + currTriplets) % MOD;

            map2.put(nums[i], map2.getOrDefault(nums[i], 0) + 1);
        }

        return (int) triplets;
    }
}