From 69be42810394a67831c0fae190fd541ae5633863 Mon Sep 17 00:00:00 2001
From: Mladen Savic <mladensavic94@gmail.com>
Date: Thu, 29 Jul 2021 15:41:01 +0200
Subject: [PATCH] EntityNotFoundException in Hibernate

---
 .../entitynotfoundexception/Category.java     | 42 +++++++++++++++++
 .../entitynotfoundexception/Item.java         | 44 ++++++++++++++++++
 .../entitynotfoundexception/User.java         | 28 ++++++++++++
 .../main/resources/META-INF/persistence.xml   | 18 ++++++++
 ...ntityNotFoundExceptionIntegrationTest.java | 45 +++++++++++++++++++
 5 files changed, 177 insertions(+)
 create mode 100644 persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Category.java
 create mode 100644 persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Item.java
 create mode 100644 persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/User.java
 create mode 100644 persistence-modules/hibernate-jpa/src/test/java/com/baeldung/hibernate/entitynotfoundexception/EntityNotFoundExceptionIntegrationTest.java

diff --git a/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Category.java b/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Category.java
new file mode 100644
index 0000000000..25d31d50c7
--- /dev/null
+++ b/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Category.java
@@ -0,0 +1,42 @@
+package com.baeldung.hibernate.entitynotfoundexception;
+
+import javax.persistence.*;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+@Entity
+public class Category implements Serializable {
+
+    @Id
+    @Column(unique = true, nullable = false)
+    private long id;
+    private String name;
+    @OneToMany
+    @JoinColumn(name = "category_id", foreignKey = @ForeignKey(ConstraintMode.NO_CONSTRAINT))
+    private List<Item> items = new ArrayList<>();
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public List<Item> getItems() {
+        return items;
+    }
+
+    public void setItems(List<Item> items) {
+        this.items = items;
+    }
+}
diff --git a/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Item.java b/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Item.java
new file mode 100644
index 0000000000..ee6f677d7d
--- /dev/null
+++ b/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/Item.java
@@ -0,0 +1,44 @@
+package com.baeldung.hibernate.entitynotfoundexception;
+
+import org.hibernate.annotations.NotFound;
+import org.hibernate.annotations.NotFoundAction;
+
+import javax.persistence.*;
+import java.io.Serializable;
+
+@Entity
+public class Item implements Serializable {
+
+    @Id
+    @Column(unique = true, nullable = false)
+    private long id;
+    private String name;
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "category_id", foreignKey = @ForeignKey(ConstraintMode.NO_CONSTRAINT))
+    @NotFound(action = NotFoundAction.IGNORE)
+    private Category category;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Category getCategory() {
+        return category;
+    }
+
+    public void setCategory(Category category) {
+        this.category = category;
+    }
+}
diff --git a/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/User.java b/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/User.java
new file mode 100644
index 0000000000..d89047195c
--- /dev/null
+++ b/persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/entitynotfoundexception/User.java
@@ -0,0 +1,28 @@
+package com.baeldung.hibernate.entitynotfoundexception;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+
+@Entity
+public class User {
+
+    @Id
+    private long id;
+    private String name;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}
diff --git a/persistence-modules/hibernate-jpa/src/main/resources/META-INF/persistence.xml b/persistence-modules/hibernate-jpa/src/main/resources/META-INF/persistence.xml
index 3482414b9d..29cd4faf05 100644
--- a/persistence-modules/hibernate-jpa/src/main/resources/META-INF/persistence.xml
+++ b/persistence-modules/hibernate-jpa/src/main/resources/META-INF/persistence.xml
@@ -119,4 +119,22 @@
             <property name="javax.persistence.jdbc.password" value=""/>
         </properties>
     </persistence-unit>
+
+    <persistence-unit name="com.baeldung.hibernate.entitynotfoundexception.h2_persistence_unit">
+        <description>EntityManager EntityNotFoundException persistence unit</description>
+        <class>com.baeldung.hibernate.entitynotfoundexception.Category</class>
+        <class>com.baeldung.hibernate.entitynotfoundexception.Item</class>
+        <class>com.baeldung.hibernate.entitynotfoundexception.User</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.generate_statistics" value="false"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
+            <property name="javax.persistence.jdbc.driver" value="org.h2.Driver"/>
+            <property name="javax.persistence.jdbc.url" value="jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1"/>
+            <property name="javax.persistence.jdbc.user" value="sa"/>
+            <property name="javax.persistence.jdbc.password" value=""/>
+        </properties>
+    </persistence-unit>
 </persistence> 
\ No newline at end of file
diff --git a/persistence-modules/hibernate-jpa/src/test/java/com/baeldung/hibernate/entitynotfoundexception/EntityNotFoundExceptionIntegrationTest.java b/persistence-modules/hibernate-jpa/src/test/java/com/baeldung/hibernate/entitynotfoundexception/EntityNotFoundExceptionIntegrationTest.java
new file mode 100644
index 0000000000..bcb4e3eb95
--- /dev/null
+++ b/persistence-modules/hibernate-jpa/src/test/java/com/baeldung/hibernate/entitynotfoundexception/EntityNotFoundExceptionIntegrationTest.java
@@ -0,0 +1,45 @@
+package com.baeldung.hibernate.entitynotfoundexception;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityNotFoundException;
+import javax.persistence.Persistence;
+import java.io.IOException;
+
+public class EntityNotFoundExceptionIntegrationTest {
+
+    private static EntityManager entityManager;
+
+    @Before
+    public void setUp() throws IOException {
+        EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("com.baeldung.hibernate.entitynotfoundexception.h2_persistence_unit");
+        entityManager = entityManagerFactory.createEntityManager();
+        entityManager.getTransaction().begin();
+
+    }
+
+
+    @Test(expected = EntityNotFoundException.class)
+    public void givenNonExistingUserId_whenGetReferenceIsUsed_thenExceptionIsThrown() {
+        User user = entityManager.getReference(User.class, 1L);
+        user.getName();
+    }
+
+    @Test(expected = EntityNotFoundException.class)
+    public void givenItem_whenManyToOneEntityIsMissing_thenExceptionIsThrown() {
+        entityManager.createNativeQuery("Insert into Item (category_id, name, id) values (1, 'test', 1)").executeUpdate();
+        entityManager.flush();
+        Item item = entityManager.find(Item.class, 1L);
+        item.getCategory().getName();
+    }
+
+    @After
+    public void tearDown() {
+        entityManager.close();
+    }
+
+}