Week4. dotProduct + mass refactoring

Author: SkyrocketStan

Week4/src/EfficientRater.java

@@ -16,8 +16,8 @@ public EfficientRater(String id) {
     myRatings = new HashMap<>();
   }
 
-  public void addRating(String movieID, Rating rating) {
-    myRatings.put(movieID, rating);
+  public void addRating(String movieID, double rating) {
+    myRatings.put(movieID, new Rating(movieID, rating));
   }
 
   public boolean hasRating(String movieID) {
@@ -44,4 +44,8 @@ public int numRatings() {
   public ArrayList<String> getItemsRated() {
     return new ArrayList<>(myRatings.keySet());
   }
+
+  public HashMap<String, Rating> getMyRatings() {
+    return myRatings;
+  }
 }

Week4/src/FirstRatings.java

@@ -76,12 +76,12 @@ static ArrayList<Rater> loadRaters(String fileName) {
       if (!idsList.contains(rater_id)) {
         Rater rater = new EfficientRater(rater_id);
         ratersList.add(rater);
-        rater.addRating(movie_id, new Rating(movie_id, rating));
+        rater.addRating(movie_id, rating);
         idsList.add(rater_id);
       } else {
         for (Rater r : ratersList) {
           if (r.getID().equals(rater_id)) {
-            r.addRating(movie_id, new Rating(movie_id, rating));
+            r.addRating(movie_id, rating);
           }
         }
       }

Week4/src/FourthRatings.java

@@ -1,5 +1,6 @@
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashMap;
 
 /**
  * The week 4 class
@@ -23,7 +24,7 @@ private Double getAverageByID(String movieID, Integer minimalRaters) {
     return 0.0;
   }
 
-  private ArrayList<Rating> getAverageRatings(int minimalRaters) {
+  public ArrayList<Rating> getAverageRatings(int minimalRaters) {
     ArrayList<Rating> list = new ArrayList<>();
     ArrayList<String> allMoviesIDs = MovieDatabase.filterBy(new TrueFilter());
     for (String movieID : allMoviesIDs) {
@@ -35,8 +36,7 @@ private ArrayList<Rating> getAverageRatings(int minimalRaters) {
     return list;
   }
 
-  private ArrayList<Rating> getAverageRatingsByFilter(
-      Integer minimalRaters, Filter filterCriteria) {
+  public ArrayList<Rating> getAverageRatingsByFilter(Integer minimalRaters, Filter filterCriteria) {
     ArrayList<Rating> ratingsList = new ArrayList<>();
     ArrayList<String> allMoviesIDs = MovieDatabase.filterBy(filterCriteria);
     Rating rating;
@@ -50,4 +50,16 @@ private ArrayList<Rating> getAverageRatingsByFilter(
     Collections.sort(ratingsList);
     return ratingsList;
   }
+
+  private double dotProduct(Rater meRater, Rater otherRater) {
+    HashMap<String, Rating> myRatings = meRater.getMyRatings();
+    double result = 0.0;
+    for (String id : myRatings.keySet()) {
+      double scale = meRater.getRating(id) - 5;
+      if (otherRater.hasRating(id)) {
+        result += scale * (otherRater.getRating(id) - 5);
+      }
+    }
+    return result;
+  }
 }

Week4/src/MovieRunnerSimilarRatings.java

@@ -0,0 +1,66 @@
+import java.util.ArrayList;
+import java.util.Collections;
+
+/** @author Stanislav Rakitov */
+public class MovieRunnerSimilarRatings {
+
+  /**
+   * Print a list of movies and their average ratings sorted by averages
+   *
+   * @param minimalRatings int specified number of ratings
+   */
+  public void printAverageRatings(int minimalRatings) {
+    FourthRatings fourthRatings = new FourthRatings();
+    ArrayList<Rating> ratedList = fourthRatings.getAverageRatings(minimalRatings);
+
+    Collections.sort(ratedList);
+    // Print the number of raters after creating a ThirdsRating object.
+    System.out.printf("Total movies with %d ratings is %d\n", minimalRatings, ratedList.size());
+
+    // Print the number of movies in the database.
+    System.out.println("The number of movies in the database is " + MovieDatabase.size());
+
+    // You will call getAverageRatings with a minimal number of raters to return an ArrayList of
+    // type Rating.
+
+    ArrayList<Rating> averageRatings = fourthRatings.getAverageRatings(minimalRatings);
+
+    // Print out how many movies with ratings are returned,
+    // then sort them, and print out the rating and title of each movie
+    System.out.printf(
+        "How many movies with ratings %d are returned: %d%n",
+        minimalRatings, averageRatings.size());
+
+    printRatingsList(averageRatings);
+  }
+
+  public void printAverageRatingsByYearAfterAndGenre(int minimalRatings, int year, String genre) {
+    FourthRatings fourthRatings = new FourthRatings();
+    AllFilters filters = new AllFilters();
+    filters.addFilter(new GenreFilter(genre));
+    filters.addFilter(new YearAfterFilter(year));
+    System.out.println(fourthRatings.getAverageRatingsByFilter(minimalRatings, filters).size());
+
+    //    System.out.printf(
+    //        "Print movie(s) with at least %d rating in \"%s\" genre produced after year" + " of %d
+    // %n",
+    //        minimalRatings, genre, year);
+    //    printRatingsList(thirdRatings.getAverageRatingsByFilter(minimalRatings, filters));
+  }
+
+  private void printRatingsList(ArrayList<Rating> averageRatingList) {
+    System.out.printf("Found %d movie(s)%n", averageRatingList.size());
+    averageRatingList.stream()
+        .sorted()
+        .forEach(
+            rating -> {
+              String movieID = rating.getItem();
+              System.out.printf("%-4s %s%n", rating.getValue(), MovieDatabase.getTitle(movieID));
+              System.out.println("     Year: " + MovieDatabase.getYear(movieID));
+              System.out.println("     Time: " + MovieDatabase.getMinutes(movieID));
+              System.out.println("     Genre(s): " + MovieDatabase.getGenres(movieID));
+              System.out.println("     Director(s): " + MovieDatabase.getDirector(movieID));
+            });
+    System.out.println("-------");
+  }
+}

Week4/src/Rater.java

@@ -1,8 +1,9 @@
 import java.util.ArrayList;
+import java.util.HashMap;
 
 public interface Rater {
   //  void addRating(String item, double rating);
-  void addRating(String movieID, Rating rating);
+  void addRating(String movieID, double rating);
 
   boolean hasRating(String item);
 
@@ -13,4 +14,6 @@ public interface Rater {
   int numRatings();
 
   ArrayList<String> getItemsRated();
+
+  HashMap<String, Rating> getMyRatings();
 }