HHH-7045 Test entity as map key with equals/hashCode based on unique key

Author: beikov

hibernate-core/src/test/java/org/hibernate/orm/test/collection/map/EntityMapKeyWithUniqueKeyEqualsHashCodeTest.java

@@ -0,0 +1,119 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.collection.map;
+
+import jakarta.persistence.CascadeType;
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.MapKeyJoinColumn;
+import jakarta.persistence.OneToMany;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.Jira;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+@DomainModel(
+		annotatedClasses = {
+				EntityMapKeyWithUniqueKeyEqualsHashCodeTest.ContainerEntity.class, EntityMapKeyWithUniqueKeyEqualsHashCodeTest.KeyEntity.class, EntityMapKeyWithUniqueKeyEqualsHashCodeTest.ValueEntity.class
+		}
+)
+@SessionFactory
+@Jira("https://hibernate.atlassian.net/browse/HHH-7045")
+public class EntityMapKeyWithUniqueKeyEqualsHashCodeTest {
+
+	@Test
+	public void test(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					ContainerEntity ce = new ContainerEntity();
+					ce.id = 1L;
+					KeyEntity k1 = new KeyEntity();
+					k1.id = 1L;
+					k1.handle = "k1";
+					KeyEntity k2 = new KeyEntity();
+					k2.id = 2L;
+					k2.handle = "k2";
+					ValueEntity v1 = new ValueEntity();
+					v1.id = 1L;
+					v1.key = k1;
+					v1.container = ce;
+					ce.values.put( k1, v1 );
+					ValueEntity v2 = new ValueEntity();
+					v2.id = 2L;
+					v2.key = k2;
+					v2.container = ce;
+					ce.values.put( k2, v2 );
+					session.persist( ce );
+
+				}
+		);
+		scope.inTransaction(
+				session -> {
+					ContainerEntity ce = session.find( ContainerEntity.class, 1L );
+					assertEquals( 2, ce.values.size() );
+				}
+		);
+
+	}
+
+	@Entity(name = "ContainerEntity")
+	public static class ContainerEntity {
+		@Id
+		public Long id;
+		@OneToMany(mappedBy = "container", cascade = CascadeType.ALL)
+		@MapKeyJoinColumn(name = "key_id")
+		public Map<KeyEntity, ValueEntity> values = new HashMap<>();
+	}
+
+	@Entity(name = "KeyEntity")
+	public static class KeyEntity {
+		@Id
+		public Long id;
+		@Column(nullable = false, unique = true)
+		public String handle;
+
+		@Override
+		public boolean equals(Object o) {
+			return o instanceof KeyEntity oke
+				&& Objects.equals( handle, oke.handle );
+		}
+
+		@Override
+		public int hashCode() {
+			return Objects.hashCode( handle );
+		}
+	}
+
+	@Entity(name = "ValueEntity")
+	public static class ValueEntity {
+		@Id
+		public Long id;
+		@ManyToOne(cascade = CascadeType.ALL)
+		public KeyEntity key;
+		@ManyToOne(cascade = CascadeType.ALL)
+		public ContainerEntity container;
+
+		@Override
+		public boolean equals(Object o) {
+			return o instanceof ValueEntity ove
+				&& Objects.equals( key, ove.key );
+		}
+
+		@Override
+		public int hashCode() {
+			return Objects.hashCode( key );
+		}
+	}
+
+}