| // |
| // Copyright 2020 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| // |
| |
| package com.google.privacy.differentialprivacy.example; |
| |
| import static java.nio.charset.StandardCharsets.UTF_8; |
| import static com.google.common.collect.ImmutableSet.toImmutableSet; |
| |
| import com.google.common.base.Splitter; |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.io.Resources; |
| import java.io.File; |
| import java.io.IOException; |
| import java.io.PrintWriter; |
| import java.time.DayOfWeek; |
| import java.time.LocalTime; |
| import java.time.format.DateTimeFormatter; |
| import java.time.format.DateTimeFormatterBuilder; |
| import java.util.EnumMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Locale; |
| import java.util.Map; |
| |
| /** Reads visitors' data and prints statistics. */ |
| class IOUtils { |
| |
| private static final String CSV_ITEM_SEPARATOR = ","; |
| private static final DateTimeFormatter TIME_FORMATTER = |
| new DateTimeFormatterBuilder() |
| // case insensitive |
| .parseCaseInsensitive() |
| // pattern |
| .appendPattern("h:mm:ss a") |
| // set Locale that uses "AM" and "PM" |
| .toFormatter(Locale.ENGLISH); |
| private static final String CSV_HOUR_COUNT_WRITE_TEMPLATE = "%d,%d\n"; |
| private static final String CSV_DAY_COUNT_WRITE_TEMPLATE = "%s,%d\n"; |
| |
| private IOUtils() {} |
| |
| /** |
| * Reads daily visitors' data. |
| * {@see #convertCsvLineWithoutDayToList} for details on the format. |
| */ |
| static ImmutableSet<Visit> readDailyVisits(String file) { |
| try { |
| List<String> visitsAsText = |
| Resources.readLines(Resources.getResource(file), UTF_8); |
| |
| return visitsAsText.stream() |
| .skip(1) |
| .map(IOUtils::convertLineToVisit) |
| .collect(toImmutableSet()); |
| } catch (IOException e) { |
| throw new IllegalStateException(e); |
| } |
| } |
| |
| /** |
| * Converts a line of format "visitorId,entryTime, minutesSpent, moneySpent, day" to |
| * {@link Visit}. |
| */ |
| private static Visit convertLineToVisit(String visitAsText) { |
| Iterator<String> splitVisit = Splitter.on(CSV_ITEM_SEPARATOR).split(visitAsText).iterator(); |
| // element 0 |
| String visitorId = splitVisit.next(); |
| // element 1 |
| LocalTime timeEntered = LocalTime.parse(splitVisit.next(), TIME_FORMATTER); |
| // element 2 |
| int timeSpent = Integer.parseInt(splitVisit.next()); |
| // element 3 |
| int moneySpent = Integer.parseInt(splitVisit.next()); |
| // element 4 |
| DayOfWeek day = DayOfWeek.of(Integer.parseInt(splitVisit.next())); |
| |
| return Visit.create(visitorId, timeEntered, timeSpent, moneySpent, day); |
| } |
| |
| /** |
| * Reads daily visitors' data. Assumes that the input file is a .csv file of format "visitorId, |
| * entryTime, minutesSpent, moneySpent, day". |
| */ |
| static VisitsForWeek readWeeklyVisits(String file) { |
| VisitsForWeek result = new VisitsForWeek(); |
| |
| try { |
| List<String> visitsAsText = |
| Resources.readLines(Resources.getResource(file), UTF_8); |
| visitsAsText.stream() |
| .skip(1) |
| .forEach(v -> { |
| Visit visit = convertLineToVisit(v); |
| result.addVisit(visit); |
| }); |
| |
| } catch (IOException e) { |
| throw new IllegalStateException(e); |
| } |
| |
| return result; |
| } |
| |
| static void writeCountsPerHourOfDay(Map<Integer, Integer> counts, String file) { |
| try (PrintWriter pw = new PrintWriter(new File(file), UTF_8.name())) { |
| counts.forEach(( |
| hour, count) -> pw.write(String.format(CSV_HOUR_COUNT_WRITE_TEMPLATE, hour, count))); |
| } catch (IOException e) { |
| throw new IllegalStateException(e); |
| } |
| } |
| |
| static void writeCountsPerDayOfWeek(EnumMap<DayOfWeek, Integer> counts, String file) { |
| try (PrintWriter pw = new PrintWriter(new File(file), UTF_8.name())) { |
| counts.forEach( |
| (day, count) -> pw.write(String.format(CSV_DAY_COUNT_WRITE_TEMPLATE, day.name(), count))); |
| } catch (IOException e) { |
| throw new IllegalStateException(e); |
| } |
| } |
| } |