calculating Moving averages - review fixes

algorithms-modules/algorithms-miscellaneous-9/pom.xml

@@ -3,19 +3,18 @@
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-
-    <artifactId>core-java-calculating-moving-averages</artifactId>
-    <name>core-java-calculating-moving-averages</name>
-    <packaging>war</packaging>
-
     <parent>
-        <groupId>com.baeldung.core-java-modules</groupId>
-        <artifactId>core-java-modules</artifactId>
-        <version>0.0.1-SNAPSHOT</version>
+        <groupId>com.baeldung</groupId>
+        <artifactId>algorithms-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
     </parent>
 
+    <artifactId>algorithms-miscellaneous-9</artifactId>
+
     <properties>
-        <commons-math3.version>3.6.1</commons-math3.version>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
     <dependencies>

algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/MovingAverageWithStreamBasedApproach.java

@@ -0,0 +1,18 @@
+package com.baeldung;
+
+import java.util.stream.DoubleStream;
+
+public class MovingAverageWithStreamBasedApproach {
+    private int windowSize;
+
+    public MovingAverageWithStreamBasedApproach(int windowSize) {
+        this.windowSize = windowSize;
+    }
+    public double calculateAverage(double[] data) {
+        return DoubleStream.of(data)
+                .skip(Math.max(0, data.length - windowSize))
+                .limit(Math.min(data.length, windowSize))
+                .summaryStatistics()
+                .getAverage();
+    }
+}

algorithms-modules/algorithms-miscellaneous-9/src/test/java/com/baeldung/ExponentialMovingAverageUnitTest.java

@@ -1,8 +1,7 @@
 package com.baeldung;
 
-import org.junit.Test;
-
 import static org.junit.Assert.assertEquals;
+import org.junit.Test;
 
 public class ExponentialMovingAverageUnitTest {
 

algorithms-modules/algorithms-miscellaneous-9/src/test/java/com/baeldung/MovingAverageByCircularBufferUnitTest.java

@@ -1,7 +1,6 @@
 package com.baeldung;
 
 import org.junit.Test;
-
 import static org.junit.Assert.assertEquals;
 
 public class MovingAverageByCircularBufferUnitTest {

algorithms-modules/algorithms-miscellaneous-9/src/test/java/com/baeldung/MovingAverageWithApacheCommonsMathUnitTest.java

@@ -1,7 +1,6 @@
 package com.baeldung;
 
 import org.junit.Test;
-
 import static org.junit.Assert.assertEquals;
 
 public class MovingAverageWithApacheCommonsMathUnitTest {

algorithms-modules/algorithms-miscellaneous-9/src/test/java/com/baeldung/MovingAverageWithStreamBasedApproachUnitTest.java

@@ -0,0 +1,38 @@
+package com.baeldung;
+
+import org.junit.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class MovingAverageWithStreamBasedApproachUnitTest {
+
+    @Test
+    public void whenEmptyDataIsPassed_shouldReturnZero() {
+        double[] data = {};
+        int windowSize = 3;
+        double expectedAverage = 0;
+        MovingAverageWithStreamBasedApproach calculator = new MovingAverageWithStreamBasedApproach(windowSize);
+        double actualAverage = calculator.calculateAverage(data);
+        assertEquals(expectedAverage, actualAverage);
+    }
+
+    @Test
+    public void whenValidDataIsPassed_shouldReturnCorrectAverage() {
+        double[] data = {10, 20, 30, 40, 50};
+        int windowSize = 3;
+        double expectedAverage = 40;
+        MovingAverageWithStreamBasedApproach calculator = new MovingAverageWithStreamBasedApproach(windowSize);
+        double actualAverage = calculator.calculateAverage(data);
+        assertEquals(expectedAverage, actualAverage);
+    }
+
+    @Test
+    public void whenValidDataIsPassedWithLongerWindowSize_shouldReturnCorrectAverage() {
+        double[] data = {10, 20, 30, 40, 50};
+        int windowSize = 5;
+        double expectedAverage = 30;
+        MovingAverageWithStreamBasedApproach calculator = new MovingAverageWithStreamBasedApproach(windowSize);
+        double actualAverage = calculator.calculateAverage(data);
+        assertEquals(expectedAverage, actualAverage);
+    }
+}

algorithms-modules/pom.xml

@@ -26,6 +26,7 @@
         <module>algorithms-searching</module>
         <module>algorithms-sorting</module>
         <module>algorithms-sorting-2</module>
+        <module>algorithms-miscellaneous-9</module>
     </modules>
 
     <properties>

core-java-modules/pom.xml

@@ -224,7 +224,6 @@
         <module>java-rmi</module>
         <module>java-spi</module>
         <module>java-websocket</module>
-        <module>core-java-calculating-moving-averages</module>
     </modules>
 
     <dependencies>