From 57b0983003677d9c7245938e83b466e9292c342e Mon Sep 17 00:00:00 2001
From: Struchkov Mark <mark@struchkov.dev>
Date: Sat, 2 Jul 2022 18:00:56 +0300
Subject: [PATCH] Problem Variant

---
 .../hibernate/nbfe/problem/ProblemMain.java   | 31 ++++++++++
 .../hibernate/nbfe/problem/domain/Post.java   | 57 +++++++++++++++++++
 .../nbfe/problem/domain/PostComment.java      | 24 ++++++++
 .../hibernate/nbfe/problem/domain/Tag.java    | 20 +++++++
 4 files changed, 132 insertions(+)
 create mode 100644 src/main/java/dev/struchkov/example/hibernate/nbfe/problem/ProblemMain.java
 create mode 100644 src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Post.java
 create mode 100644 src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/PostComment.java
 create mode 100644 src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Tag.java

diff --git a/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/ProblemMain.java b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/ProblemMain.java
new file mode 100644
index 0000000..5964c05
--- /dev/null
+++ b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/ProblemMain.java
@@ -0,0 +1,31 @@
+package dev.struchkov.example.hibernate.nbfe.problem;
+
+import dev.struchkov.example.hibernate.nbfe.problem.domain.Post;
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.EntityManagerFactory;
+import jakarta.persistence.Persistence;
+
+import java.util.List;
+
+public class ProblemMain {
+
+    public static void main(String[] args) {
+        final EntityManagerFactory emf = Persistence.createEntityManagerFactory("Blog");
+        final EntityManager entityManager = emf.createEntityManager();
+
+        final List<Post> posts = entityManager.createQuery(
+                        """
+                                SELECT p
+                                FROM Post p
+                                LEFT JOIN FETCH p.comments
+                                LEFT JOIN FETCH p.tags
+                                WHERE p.id BETWEEN :minId AND :maxId
+                                """, Post.class
+                )
+                .setParameter("minId", 1L)
+                .setParameter("maxId", 50L)
+                .getResultList();
+    }
+
+
+}
diff --git a/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Post.java b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Post.java
new file mode 100644
index 0000000..761ba30
--- /dev/null
+++ b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Post.java
@@ -0,0 +1,57 @@
+package dev.struchkov.example.hibernate.nbfe.problem.domain;
+
+import jakarta.persistence.CascadeType;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.JoinTable;
+import jakarta.persistence.ManyToMany;
+import jakarta.persistence.OneToMany;
+import lombok.Getter;
+import lombok.Setter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Entity
+@Getter
+@Setter
+public class Post {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String title;
+
+    @OneToMany(
+            mappedBy = "post",
+            cascade = CascadeType.ALL,
+            orphanRemoval = true
+    )
+    private List<PostComment> comments = new ArrayList<>();
+
+    @ManyToMany(
+            cascade = {
+                    CascadeType.PERSIST,
+                    CascadeType.MERGE
+            }
+    )
+    @JoinTable(
+            name = "post_tag",
+            joinColumns = @JoinColumn(name = "post_id"),
+            inverseJoinColumns = @JoinColumn(name = "tag_id")
+    )
+    private List<Tag> tags = new ArrayList<>();
+
+    public void addComment(PostComment postComment) {
+        postComment.setPost(this);
+        comments.add(postComment);
+    }
+
+    public void addTag(Tag tag) {
+        tags.add(tag);
+    }
+
+}
diff --git a/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/PostComment.java b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/PostComment.java
new file mode 100644
index 0000000..5e67aca
--- /dev/null
+++ b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/PostComment.java
@@ -0,0 +1,24 @@
+package dev.struchkov.example.hibernate.nbfe.problem.domain;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import lombok.Getter;
+import lombok.Setter;
+
+@Entity
+@Getter
+@Setter
+public class PostComment {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    @ManyToOne
+    private Post post;
+
+    private String review;
+
+}
diff --git a/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Tag.java b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Tag.java
new file mode 100644
index 0000000..b321125
--- /dev/null
+++ b/src/main/java/dev/struchkov/example/hibernate/nbfe/problem/domain/Tag.java
@@ -0,0 +1,20 @@
+package dev.struchkov.example.hibernate.nbfe.problem.domain;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import lombok.Getter;
+import lombok.Setter;
+
+@Entity
+@Getter
+@Setter
+public class Tag {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String name;
+
+}