My brain hurts...

CommandBinder.java

            ArrayList<String> serialized = new ArrayList<>();
            Map<String, Map<Player, HashMap<Material, Boolean>>> rows = table.rowMap();

            for (Map.Entry<String, Map<Player, HashMap<Material, Boolean>>> row : rows.entrySet()) {
                for (Map.Entry<Player, HashMap<Material, Boolean>> column : row.getValue().entrySet()) {
                    for (Map.Entry<Material, Boolean> secondColumn : column.getValue().entrySet()) {
                        serialized.add(serializer(row.getKey(), column.getKey(), secondColumn.getKey(), secondColumn.getValue()));
                    }
                }
            }