[JAVA-12051] Moved code to core-java-streams-simple for ebook (#14889)

core-java-modules/core-java-16/README.md

@@ -4,5 +4,4 @@
 - [Guide to mapMulti in Stream API](https://www.baeldung.com/java-mapmulti)
 - [Collecting Stream Elements into a List in Java](https://www.baeldung.com/java-stream-to-list-collecting)
 - [New Features in Java 16](https://www.baeldung.com/java-16-new-features)
-- [Guide to Java 8 groupingBy Collector](https://www.baeldung.com/java-groupingby-collector)
 - [Value-Based Classes in Java](https://www.baeldung.com/java-value-based-classes)

core-java-modules/core-java-16/src/main/java/com/baeldung/java_16_features/groupingby/BlogPost.java

@@ -1,43 +0,0 @@
-package com.baeldung.java_16_features.groupingby;
-
-import java.util.IntSummaryStatistics;
-
-
-public class BlogPost {
-
-    private String title;
-    private String author;
-    private BlogPostType type;
-    private int likes;
-    record AuthPostTypesLikes(String author, BlogPostType type, int likes) {};
-    record PostCountTitlesLikesStats(long postCount, String titles, IntSummaryStatistics likesStats){};
-    record TitlesBoundedSumOfLikes(String titles, int boundedSumOfLikes) {};
-
-    public BlogPost(String title, String author, BlogPostType type, int likes) {
-        this.title = title;
-        this.author = author;
-        this.type = type;
-        this.likes = likes;
-    }
-
-    public String getTitle() {
-        return title;
-    }
-
-    public String getAuthor() {
-        return author;
-    }
-
-    public BlogPostType getType() {
-        return type;
-    }
-
-    public int getLikes() {
-        return likes;
-    }
-
-    @Override
-    public String toString() {
-        return "BlogPost{" + "title='" + title + '\'' + ", type=" + type + ", likes=" + likes + '}';
-    }
-}

core-java-modules/core-java-16/src/main/java/com/baeldung/java_16_features/groupingby/BlogPostType.java

@@ -1,5 +0,0 @@
-package com.baeldung.java_16_features.groupingby;
-
-public enum BlogPostType {
-    NEWS, REVIEW, GUIDE
-}

core-java-modules/core-java-16/src/main/java/com/baeldung/java_16_features/groupingby/Tuple.java

@@ -1,41 +0,0 @@
-package com.baeldung.java_16_features.groupingby;
-
-import java.util.Objects;
-
-public class Tuple {
-    private final BlogPostType type;
-    private final String author;
-
-    public Tuple(BlogPostType type, String author) {
-        this.type = type;
-        this.author = author;
-    }
-
-    public BlogPostType getType() {
-        return type;
-    }
-
-    public String getAuthor() {
-        return author;
-    }
-
-    @Override
-    public boolean equals(Object o) {
-        if (this == o)
-            return true;
-        if (o == null || getClass() != o.getClass())
-            return false;
-        Tuple tuple = (Tuple) o;
-        return type == tuple.type && author.equals(tuple.author);
-    }
-
-    @Override
-    public int hashCode() {
-        return Objects.hash(type, author);
-    }
-
-    @Override
-    public String toString() {
-        return "Tuple{" + "type=" + type + ", author='" + author + '\'' + '}';
-    }
-}