rotting oranges

class Solution {
    int freshCount = 0;
    Queue<Pair> queue = new LinkedList<>();

    public int orangesRotting(int[][] grid) {

        for (int i = 0; i < grid.length; i++) {
            for (int j = 0; j < grid[i].length; j++) {
                if (grid[i][j] == 2) {
                    queue.offer(new Pair(i,j)); // Rotten oranges
                }
                if (grid[i][j] == 1) freshCount++;
            }
        }
        int count = 0;
        while (!queue.isEmpty()) {
            rotOranges(grid);
            count++;
        }
        if (freshCount > 0) return -1;
        return count == 0 ? count : count-1;
    }

    private void rotOranges(int[][] grid) {

        int size = queue.size();
        for (int i = 0; i < size; i++) {
            Pair indexes = queue.poll();

            List<Pair> nextRotten = getAlongSide(grid, indexes.i, indexes.j);
            for(Pair p: nextRotten) {

                grid[p.i][p.j] = 2;
                freshCount--;
                queue.offer(p);

            }
        }
    }

    public List<Pair> getAlongSide(int[][] grid, int i, int j) {
        List<Pair> result = new ArrayList<>();
        if (isSafeDown(grid, i, j)) result.add(new Pair(i+1, j));
        if (isSafeUp(grid, i, j)) result.add(new Pair(i-1, j));
        if (isSafeLeft(j, grid[i])) result.add(new Pair(i, j+1));
        if (isSafeRight(j, grid[i])) result.add(new Pair(i, j-1));
        return result;
    }

    private static boolean isSafeUp(int[][] grid, int i, int j) {
        return i - 1 >= 0 && grid[i - 1][j] == 1;
    }

    private static boolean isSafeRight(int j, int[] grid) {
        return j - 1 >= 0 && grid[j - 1] == 1;
    }

    private static boolean isSafeDown(int[][] grid, int i, int j) {
        return i + 1 < grid.length && grid[i + 1][j] == 1;
    }

    private static boolean isSafeLeft(int j, int[] grid) {
        return j + 1 < grid.length && grid[j + 1] == 1;
    }
}

class Pair {
    int i, j;
    public Pair(int i, int j) {
        this.i = i;
        this.j = j;
    }
}