From 7c1065b494a05299addb9f0ada8fdba786ac91e4 Mon Sep 17 00:00:00 2001 From: panos-kakos <102670093+panos-kakos@users.noreply.github.com> Date: Fri, 10 Nov 2023 14:15:28 +0000 Subject: [PATCH] [JAVA-26439] Moved code related to "Guide to Stream.reduce()" to ebook module (#15170) --- .../streamreduce/application/Application.java | 62 ------------------- .../streamreduce/entities/Rating.java | 39 ------------ .../streamreduce/entities/Review.java | 28 --------- .../baeldung/streamreduce/entities/User.java | 30 --------- .../streamreduce/utilities/NumberUtils.java | 52 ---------------- .../streams/reduce/entities/User.java | 7 ++- .../reduce}/StreamReduceManualTest.java | 15 +++-- 7 files changed, 15 insertions(+), 218 deletions(-) delete mode 100644 core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/application/Application.java delete mode 100644 core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Rating.java delete mode 100644 core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Review.java delete mode 100644 core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/User.java delete mode 100644 core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/utilities/NumberUtils.java rename core-java-modules/{core-java-8/src/test/java/com/baeldung/streamreduce/tests => core-java-streams-simple/src/test/java/com/baeldung/streams/reduce}/StreamReduceManualTest.java (95%) diff --git a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/application/Application.java b/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/application/Application.java deleted file mode 100644 index 00fc45ccae..0000000000 --- a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/application/Application.java +++ /dev/null @@ -1,62 +0,0 @@ -package com.baeldung.streamreduce.application; - -import com.baeldung.streamreduce.entities.User; -import com.baeldung.streamreduce.utilities.NumberUtils; -import java.util.ArrayList; -import java.util.Arrays; -import java.util.List; - -public class Application { - - public static void main(String[] args) { - List numbers = Arrays.asList(1, 2, 3, 4, 5, 6); - int result1 = numbers.stream().reduce(0, (a, b) -> a + b); - System.out.println(result1); - - int result2 = numbers.stream().reduce(0, Integer::sum); - System.out.println(result2); - - List letters = Arrays.asList("a", "b", "c", "d", "e"); - String result3 = letters.stream().reduce("", (a, b) -> a + b); - System.out.println(result3); - - String result4 = letters.stream().reduce("", String::concat); - System.out.println(result4); - - String result5 = letters.stream().reduce("", (a, b) -> a.toUpperCase() + b.toUpperCase()); - System.out.println(result5); - - List users = Arrays.asList(new User("John", 30), new User("Julie", 35)); - int result6 = users.stream().reduce(0, (partialAgeResult, user) -> partialAgeResult + user.getAge(), Integer::sum); - System.out.println(result6); - - String result7 = letters.parallelStream().reduce("", String::concat); - System.out.println(result7); - - int result8 = users.parallelStream().reduce(0, (partialAgeResult, user) -> partialAgeResult + user.getAge(), Integer::sum); - System.out.println(result8); - - List userList = new ArrayList<>(); - for (int i = 0; i <= 1000000; i++) { - userList.add(new User("John" + i, i)); - } - - long t1 = System.currentTimeMillis(); - int result9 = userList.stream().reduce(0, (partialAgeResult, user) -> partialAgeResult + user.getAge(), Integer::sum); - long t2 = System.currentTimeMillis(); - System.out.println(result9); - System.out.println("Sequential stream time: " + (t2 - t1) + "ms"); - - long t3 = System.currentTimeMillis(); - int result10 = userList.parallelStream().reduce(0, (partialAgeResult, user) -> partialAgeResult + user.getAge(), Integer::sum); - long t4 = System.currentTimeMillis(); - System.out.println(result10); - System.out.println("Parallel stream time: " + (t4 - t3) + "ms"); - - int result11 = NumberUtils.divideListElements(numbers, 1); - System.out.println(result11); - - int result12 = NumberUtils.divideListElementsWithExtractedTryCatchBlock(numbers, 0); - System.out.println(result12); - } -} diff --git a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Rating.java b/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Rating.java deleted file mode 100644 index c4d0276256..0000000000 --- a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Rating.java +++ /dev/null @@ -1,39 +0,0 @@ -package com.baeldung.streamreduce.entities; - -import java.util.ArrayList; -import java.util.List; - -public class Rating { - - double points; - List reviews = new ArrayList<>(); - - public Rating() {} - - public void add(Review review) { - reviews.add(review); - computeRating(); - } - - private double computeRating() { - double totalPoints = reviews.stream().map(Review::getPoints).reduce(0, Integer::sum); - this.points = totalPoints / reviews.size(); - return this.points; - } - - public static Rating average(Rating r1, Rating r2) { - Rating combined = new Rating(); - combined.reviews = new ArrayList<>(r1.reviews); - combined.reviews.addAll(r2.reviews); - combined.computeRating(); - return combined; - } - - public double getPoints() { - return points; - } - - public List getReviews() { - return reviews; - } -} diff --git a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Review.java b/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Review.java deleted file mode 100644 index 03cde8a9c8..0000000000 --- a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/Review.java +++ /dev/null @@ -1,28 +0,0 @@ -package com.baeldung.streamreduce.entities; - -public class Review { - - int points; - String review; - - public Review(int points, String review) { - this.points = points; - this.review = review; - } - - public int getPoints() { - return points; - } - - public void setPoints(int points) { - this.points = points; - } - - public String getReview() { - return review; - } - - public void setReview(String review) { - this.review = review; - } -} diff --git a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/User.java b/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/User.java deleted file mode 100644 index 20c12d7920..0000000000 --- a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/entities/User.java +++ /dev/null @@ -1,30 +0,0 @@ -package com.baeldung.streamreduce.entities; - -public class User { - - private final String name; - private final int age; - private final Rating rating = new Rating(); - - public User(String name, int age) { - this.name = name; - this.age = age; - } - - public String getName() { - return name; - } - - public int getAge() { - return age; - } - - public Rating getRating() { - return rating; - } - - @Override - public String toString() { - return "User{" + "name=" + name + ", age=" + age + '}'; - } -} diff --git a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/utilities/NumberUtils.java b/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/utilities/NumberUtils.java deleted file mode 100644 index a2325cc701..0000000000 --- a/core-java-modules/core-java-8/src/main/java/com/baeldung/streamreduce/utilities/NumberUtils.java +++ /dev/null @@ -1,52 +0,0 @@ -package com.baeldung.streamreduce.utilities; - -import java.util.List; -import java.util.function.BiFunction; -import java.util.logging.Level; -import java.util.logging.Logger; - -public abstract class NumberUtils { - - private static final Logger LOGGER = Logger.getLogger(NumberUtils.class.getName()); - - public static int divideListElements(List values, Integer divider) { - return values.stream() - .reduce(0, (a, b) -> { - try { - return a / divider + b / divider; - } catch (ArithmeticException e) { - LOGGER.log(Level.INFO, "Arithmetic Exception: Division by Zero"); - } - return 0; - }); - } - - public static int divideListElementsWithExtractedTryCatchBlock(List values, int divider) { - return values.stream().reduce(0, (a, b) -> divide(a, divider) + divide(b, divider)); - } - - public static int divideListElementsWithApplyFunctionMethod(List values, int divider) { - BiFunction division = (a, b) -> a / b; - return values.stream().reduce(0, (a, b) -> applyFunction(division, a, divider) + applyFunction(division, b, divider)); - } - - private static int divide(int value, int factor) { - int result = 0; - try { - result = value / factor; - } catch (ArithmeticException e) { - LOGGER.log(Level.INFO, "Arithmetic Exception: Division by Zero"); - } - return result; - } - - private static int applyFunction(BiFunction function, int a, int b) { - try { - return function.apply(a, b); - } - catch(Exception e) { - LOGGER.log(Level.INFO, "Exception occurred!"); - } - return 0; - } -} diff --git a/core-java-modules/core-java-streams-simple/src/main/java/com/baeldung/streams/reduce/entities/User.java b/core-java-modules/core-java-streams-simple/src/main/java/com/baeldung/streams/reduce/entities/User.java index 610bd93b22..07c627005a 100644 --- a/core-java-modules/core-java-streams-simple/src/main/java/com/baeldung/streams/reduce/entities/User.java +++ b/core-java-modules/core-java-streams-simple/src/main/java/com/baeldung/streams/reduce/entities/User.java @@ -4,6 +4,7 @@ public class User { private final String name; private final int age; + private final Rating rating = new Rating(); public User(String name, int age) { this.name = name; @@ -17,7 +18,11 @@ public class User { public int getAge() { return age; } - + + public Rating getRating() { + return rating; + } + @Override public String toString() { return "User{" + "name=" + name + ", age=" + age + '}'; diff --git a/core-java-modules/core-java-8/src/test/java/com/baeldung/streamreduce/tests/StreamReduceManualTest.java b/core-java-modules/core-java-streams-simple/src/test/java/com/baeldung/streams/reduce/StreamReduceManualTest.java similarity index 95% rename from core-java-modules/core-java-8/src/test/java/com/baeldung/streamreduce/tests/StreamReduceManualTest.java rename to core-java-modules/core-java-streams-simple/src/test/java/com/baeldung/streams/reduce/StreamReduceManualTest.java index 602bdd069e..2931384c94 100644 --- a/core-java-modules/core-java-8/src/test/java/com/baeldung/streamreduce/tests/StreamReduceManualTest.java +++ b/core-java-modules/core-java-streams-simple/src/test/java/com/baeldung/streams/reduce/StreamReduceManualTest.java @@ -1,15 +1,18 @@ -package com.baeldung.streamreduce.tests; +package com.baeldung.streams.reduce; + +import static org.assertj.core.api.Assertions.assertThat; -import com.baeldung.streamreduce.entities.Rating; -import com.baeldung.streamreduce.entities.Review; -import com.baeldung.streamreduce.entities.User; -import com.baeldung.streamreduce.utilities.NumberUtils; import java.util.ArrayList; import java.util.Arrays; import java.util.List; -import static org.assertj.core.api.Assertions.assertThat; + import org.junit.Test; +import com.baeldung.streams.reduce.entities.Rating; +import com.baeldung.streams.reduce.entities.Review; +import com.baeldung.streams.reduce.entities.User; +import com.baeldung.streams.reduce.utilities.NumberUtils; + public class StreamReduceManualTest { @Test