Movie recommender centli

.classpath

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" output="target/classes" path="src/main/java">
+		<attributes>
+			<attribute name="optional" value="true"/>
+			<attribute name="maven.pomderived" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="src" output="target/test-classes" path="src/test/java">
+		<attributes>
+			<attribute name="optional" value="true"/>
+			<attribute name="maven.pomderived" value="true"/>
+			<attribute name="test" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11">
+		<attributes>
+			<attribute name="maven.pomderived" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="con" path="org.eclipse.m2e.MAVEN2_CLASSPATH_CONTAINER">
+		<attributes>
+			<attribute name="maven.pomderived" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="src" path="target/generated-sources/annotations">
+		<attributes>
+			<attribute name="optional" value="true"/>
+			<attribute name="maven.pomderived" value="true"/>
+			<attribute name="ignore_optional_problems" value="true"/>
+			<attribute name="m2e-apt" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="src" output="target/test-classes" path="target/generated-test-sources/test-annotations">
+		<attributes>
+			<attribute name="optional" value="true"/>
+			<attribute name="maven.pomderived" value="true"/>
+			<attribute name="ignore_optional_problems" value="true"/>
+			<attribute name="m2e-apt" value="true"/>
+			<attribute name="test" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="output" path="target/classes"/>
+</classpath>

.project

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>big-data</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.m2e.core.maven2Builder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.m2e.core.maven2Nature</nature>
+	</natures>
+	<filteredResources>
+		<filter>
+			<id>1635192007554</id>
+			<name></name>
+			<type>30</type>
+			<matcher>
+				<id>org.eclipse.core.resources.regexFilterMatcher</id>
+				<arguments>node_modules|.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__</arguments>
+			</matcher>
+		</filter>
+	</filteredResources>
+</projectDescription>

.settings/org.eclipse.core.resources.prefs

@@ -0,0 +1,4 @@
+eclipse.preferences.version=1
+encoding//src/main/java=UTF-8
+encoding//src/test/java=UTF-8
+encoding/<project>=UTF-8

.settings/org.eclipse.jdt.apt.core.prefs

@@ -0,0 +1,2 @@
+eclipse.preferences.version=1
+org.eclipse.jdt.apt.aptEnabled=false

.settings/org.eclipse.jdt.core.prefs

@@ -0,0 +1,9 @@
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=11
+org.eclipse.jdt.core.compiler.compliance=11
+org.eclipse.jdt.core.compiler.problem.enablePreviewFeatures=disabled
+org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
+org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=ignore
+org.eclipse.jdt.core.compiler.processAnnotations=disabled
+org.eclipse.jdt.core.compiler.release=disabled
+org.eclipse.jdt.core.compiler.source=11

.settings/org.eclipse.m2e.core.prefs

@@ -0,0 +1,4 @@
+activeProfiles=
+eclipse.preferences.version=1
+resolveWorkspaceProjects=true
+version=1

pom.xml

@@ -12,6 +12,8 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <maven.compiler.target>11</maven.compiler.target>
+    <maven.compiler.source>11</maven.compiler.source>
   </properties>
 
   <dependencies>
@@ -26,5 +28,15 @@
           <version>4.7</version>
           <scope>test</scope>
       </dependency>
+      <dependency>
+          <groupId>org.slf4j</groupId>
+          <artifactId>slf4j-api</artifactId>
+          <version>1.7.32</version>
+      </dependency>
+      <dependency>
+          <groupId>org.slf4j</groupId>
+          <artifactId>slf4j-simple</artifactId>
+          <version>1.7.5</version>
+      </dependency>
   </dependencies>
 </project>

src/main/java/nearsoft/academy/bigdata/recommendation/MovieRecommender.java

@@ -0,0 +1,210 @@
+package nearsoft.academy.bigdata.recommendation;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.zip.GZIPInputStream;
+
+import org.apache.mahout.cf.taste.common.TasteException;
+import org.apache.mahout.cf.taste.impl.model.file.FileDataModel;
+import org.apache.mahout.cf.taste.impl.neighborhood.ThresholdUserNeighborhood;
+import org.apache.mahout.cf.taste.impl.recommender.GenericUserBasedRecommender;
+import org.apache.mahout.cf.taste.impl.similarity.PearsonCorrelationSimilarity;
+import org.apache.mahout.cf.taste.model.DataModel;
+import org.apache.mahout.cf.taste.neighborhood.UserNeighborhood;
+import org.apache.mahout.cf.taste.recommender.RecommendedItem;
+import org.apache.mahout.cf.taste.recommender.UserBasedRecommender;
+import org.apache.mahout.cf.taste.similarity.UserSimilarity;
+
+
+public class MovieRecommender {
+    private static String DATA_PATH = System.getProperty("user.dir") + "/src/main/data/";
+    private static String CSV_DATA_PATH = DATA_PATH + "/data.csv";
+    private static String USERS_INDEX_PATH = DATA_PATH + "users.csv";
+    private static String PRODUCTS_INDEX_PATH = DATA_PATH + "products.csv";
+
+    private static int NUM_OF_REGISTRABLE_ITEMS = 3;
+
+    private Map<String, Integer> products = new HashMap<String,Integer>();
+    private Map<Integer, String> productsReverse = new HashMap<Integer,String>();
+    private Map<String, Integer> users = new HashMap<String,Integer>();
+    private String dataFilePath;
+    private int totalUsers = 0;
+    private int totalProducts = 0;
+    private int totalReviews = 0;
+
+    private DataModel model;
+    private UserSimilarity similarity;
+    private UserNeighborhood neighborhood;
+    private UserBasedRecommender recommender;
+
+    public MovieRecommender(String dataFilePath) throws IOException, TasteException {
+        this.dataFilePath = dataFilePath;
+
+        try {
+            readFile();
+        } catch (IOException error) {
+            error.printStackTrace();
+        }
+
+
+        this.model = new FileDataModel(new File(CSV_DATA_PATH));
+        this.similarity = new PearsonCorrelationSimilarity(this.model);
+        this.neighborhood = new ThresholdUserNeighborhood(0.1, this.similarity, this.model);
+        this.recommender = new GenericUserBasedRecommender(this.model, this.neighborhood, this.similarity);
+
+        this.totalProducts = this.model.getNumItems();
+        this.totalUsers = this.model.getNumUsers();
+    }
+
+    private void readFile () throws IOException {
+        // Those methods allow us read the ".txt.gz" file without unzip it.
+        FileInputStream file = new FileInputStream(this.dataFilePath);
+        GZIPInputStream gzip = new GZIPInputStream(file);
+        InputStreamReader isr = new InputStreamReader(gzip);
+        BufferedReader br = new BufferedReader(isr);
+
+        List<String> dataParts = new ArrayList<String>();
+        String line;
+
+        FileWriter fileWriter = new FileWriter(CSV_DATA_PATH); // Create a csv file
+
+        while ((line = br.readLine()) != null) {
+            String[] registrables = {"product/productId:", "review/userId:", "review/score:"}; // Indicate only the data we need (user id, movie & score)
+
+            String[] parts = line.split(" ");
+
+            Boolean idRequiredField = Arrays.asList(registrables).contains(parts[0]);
+
+            if (idRequiredField) {
+                dataParts.add(parts[1]);
+            }
+
+            if (dataParts.size() == NUM_OF_REGISTRABLE_ITEMS) {
+                String userId = dataParts.get(1);
+                String productId = dataParts.get(0);
+                String score = dataParts.get(2);
+
+                int productIdxVal = (this.products.containsKey(productId) ? this.products.get(productId) : totalProducts);
+                int userIdxVal = (this.users.containsKey(userId) ? this.users.get(userId) : totalUsers);
+
+                String mixedData = userIdxVal + "," + productIdxVal + "," + score + "\n";
+                fileWriter.write(mixedData);
+
+                this.setOccurrences(productId, userId);
+
+                dataParts = new ArrayList<String>();
+            }
+        }
+
+        fileWriter.close();
+        br.close();
+    }
+
+    private void setOccurrences (String productId, String userId) {
+
+        this.totalReviews++; // Count reviews
+
+        // Count products
+        if (!this.products.containsKey(productId)) {
+            this.products.put(productId, totalProducts);
+            this.productsReverse.put(totalProducts, productId);
+
+            try {
+                FileWriter fr = new FileWriter(PRODUCTS_INDEX_PATH, true);
+                fr.write(productId + "," + totalProducts + "\n");
+                fr.close();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+            totalProducts++;
+        }
+
+
+        if (!this.users.containsKey(userId)) {// Count users
+            this.users.put(userId, totalUsers);
+
+            try {
+                FileWriter fr = new FileWriter(USERS_INDEX_PATH, true);
+                fr.write(userId + "," + totalUsers + "\n");
+                fr.close();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+            totalUsers++;
+        }
+    }
+
+    private void retrieveData () throws IOException {
+        this.model = new FileDataModel(new File(CSV_DATA_PATH));
+
+        BufferedReader productReader = new BufferedReader(new FileReader(PRODUCTS_INDEX_PATH));// Read products
+        String product;
+
+        while ((product = productReader.readLine()) != null) {
+            String[] productParts = product.split(",");
+            String productId = productParts[0];
+            int idx = Integer.parseInt(productParts[1]);
+
+            this.products.put(productId, idx);
+            this.productsReverse.put(idx, productId);
+        }
+        productReader.close();
+
+        BufferedReader usersReader = new BufferedReader(new FileReader(USERS_INDEX_PATH));// Read users
+        String user;
+
+        while ((user = usersReader.readLine()) != null) {
+            String[] userParts = user.split(",");
+            String userId = userParts[0];
+            int idx = Integer.parseInt(userParts[1]);
+
+            this.users.put(userId, idx);
+        }
+        usersReader.close();
+
+        BufferedReader reviewsReader = new BufferedReader(new FileReader(CSV_DATA_PATH));// Count reviews
+
+        while (reviewsReader.readLine() != null) {
+            this.totalReviews++;
+        }
+
+        reviewsReader.close();
+    }
+
+    public int getTotalReviews() {
+        return this.totalReviews;
+    }
+
+    public int getTotalProducts () {
+        return this.totalProducts;
+    }
+
+    public int getTotalUsers () {
+        return this.totalUsers;
+    }
+
+    public List<String> getRecommendationsForUser (String userID) throws TasteException {
+        List<String> recommendations = new ArrayList<String>();
+
+        long user = users.get(userID);
+
+        List<RecommendedItem> recommendationss = this.recommender.recommend(user, 3);
+
+        for (RecommendedItem recommendation : recommendationss) {
+            int idOfProduct = (int) recommendation.getItemID();
+            recommendations.add(productsReverse.get(idOfProduct));
+        }
+
+        return recommendations;
+    }
+}

src/test/java/nearsoft/academy/bigdata/recommendation/MovieRecommenderTest.java

@@ -13,9 +13,13 @@
 public class MovieRecommenderTest {
     @Test
     public void testDataInfo() throws IOException, TasteException {
-        //download movies.txt.gz from 
+        //download movies.txt.gz from:
         //    http://snap.stanford.edu/data/web-Movies.html
-        MovieRecommender recommender = new MovieRecommender("/path/to/movies.txt.gz");
+
+        // Obtain the current directory
+        String ROOT_PATH = System.getProperty("user.dir");
+
+        MovieRecommender recommender = new MovieRecommender(ROOT_PATH + "/src/main/data/movies.txt.gz");
         assertEquals(7911684, recommender.getTotalReviews());
         assertEquals(253059, recommender.getTotalProducts());
         assertEquals(889176, recommender.getTotalUsers());