JPA single-table 继承映射和到子 类 的两个关系失败并出现意外结果 (Hibernate)
JPA single-table inheritance mapping and two relationships to sub classes fails with unexpected result (Hibernate )
我们有一个简单的单一 table 映射，一艘附有图像和文档（均为附件的子 类）的船：
@Entity
@Table(name = "SHIPS")
public class Ship implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "ID")
private Long id;
@Basic(optional = false)
@Column(name = "NAME")
private String name;
@OneToMany(mappedBy = "ship", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
// @Where(clause = "DISCR = 'I'")
private List<Image> images = new ArrayList<>();
@OneToMany(mappedBy = "ship", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
// @Where(clause = "DISCR = 'D'")
private List<Document> documents = new ArrayList<>();
public Ship() {}
public Ship(Long id, String name) {
this.id = id;
this.name = 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;
}
public List<Image> getImages() {
return images;
}
public void setImages(List<Image> images) {
this.images = images;
}
public List<Document> getDocuments() {
return documents;
}
public void setDocuments(List<Document> documents) {
this.documents = documents;
}
}
@Entity
@Table(name = "ATTACHMENTS")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "DISCR")
public abstract class BaseAttachment implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "ID")
protected Long id;
@Basic(optional = false)
@Column(name = "DISCR", insertable = false, updatable = false)
protected String discr;
@Basic(optional = false)
@Column(name = "FILE_NAME")
protected String fileName;
// @Lob
// @Basic(optional = false)
// @Column(name = "ORIGINAL_DATA")
// protected byte[] originalData;
@ManyToOne(optional = false, fetch = FetchType.LAZY)
@JoinColumn(name = "SHIP_ID", referencedColumnName = "ID")
protected Ship ship;
public BaseAttachment() {}
public BaseAttachment(Long id, String fileName) {
this.id = id;
this.fileName = fileName;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getDiscr() {
return discr;
}
public void setDiscr(String discr) {
this.discr = discr;
}
public String getFileName() {
return fileName;
}
public void setFileName(String fileName) {
this.fileName = fileName;
}
// public byte[] getOriginalData() {
// return originalData;
// }
//
// public void setOriginalData(byte[] originalData) {
// this.originalData = originalData;
// }
public Ship getShip() {
return ship;
}
public void setShip(Ship ship) {
this.ship = ship;
}
}
@Entity
@DiscriminatorValue("I")
public class Image extends BaseAttachment {
private static final long serialVersionUID = 1L;
@Column(name = "ALTERNATIVE_TEXT")
private String alternativeText;
public Image() {}
public Image(Long id, String fileName) {
super(id, fileName);
}
public String getAlternativeText() {
return alternativeText;
}
public void setAlternativeText(String alternativeText) {
this.alternativeText = alternativeText;
}
}
@Entity
@DiscriminatorValue("D")
public class Document extends BaseAttachment {
private static final long serialVersionUID = 1L;
public Document() {}
public Document(Long id, String fileName) {
super(id, fileName);
}
}
我为 Hibernate 创建了一个测试用例：
@TestForIssue( jiraKey = "HHH-99999")
public class TwoRelationshipsToSubclassTest extends BaseEntityManagerFunctionalTestCase {
@Override
public Class<?>[] getAnnotatedClasses() {
return new Class<?>[]{Ship.class, BaseAttachment.class, Image.class, Document.class};
}
@Override
protected void addConfigOptions(Map options) {
options.put( AvailableSettings.USE_SECOND_LEVEL_CACHE, "false" );
options.put( AvailableSettings.SHOW_SQL, "true" );
options.put( AvailableSettings.FORMAT_SQL, "true" );
options.put( AvailableSettings.ENABLE_LAZY_LOAD_NO_TRANS, "true" );
}
@Before
public void prepare() {
doInJPA( this::entityManagerFactory, em -> {
Ship ship = new Ship(1L, "Titanic");
// images
Image image1 = new Image(1L, "abc.png");
image1.setShip(ship);
Image image2 = new Image(2L, "def.jpg");
image2.setShip(ship);
// documents
Document document1 = new Document(3L, "ghi.docx");
document1.setShip(ship);
Document document2 = new Document(4L, "jkl.pdf");
document2.setShip(ship);
Document document3 = new Document(5L, "mno.txt");
document3.setShip(ship);
// images relationship
ship.getImages().add(image1);
ship.getImages().add(image2);
// documents relationship
ship.getDocuments().add(document1);
ship.getDocuments().add(document2);
ship.getDocuments().add(document3);
// persist
em.persist( ship );
});
}
/**
* Use --debug to see the SQL being run + the sysouts.
*/
@Test
public void test() {
doInJPA( this::entityManagerFactory, em -> {
Ship ship = em.find( Ship.class, 1L );
Assert.assertNotNull("Ship not found!", ship);
List<Image> images = ship.getImages();
Assert.assertEquals(2, images.size());
List<Document> documents = ship.getDocuments();
Assert.assertEquals(3, documents.size());
} );
}
}
失败：
expected:<2> but was:<5>
Expected :2
Actual :5
<Click to see difference>
java.lang.AssertionError: expected:<2> but was:<5>
at org.junit.Assert.fail(Assert.java:88)
at org.junit.Assert.failNotEquals(Assert.java:834)
at org.junit.Assert.assertEquals(Assert.java:645)
at org.junit.Assert.assertEquals(Assert.java:631)
at org.hibernate.jpa.test.inheritance.singletable.TwoRelationshipsToSubclassTest.lambda$test(TwoRelationshipsToSubclassTest.java:68)
at org.hibernate.testing.transaction.TransactionUtil.doInJPA(TransactionUtil.java:206)
at org.hibernate.testing.transaction.TransactionUtil.doInJPA(TransactionUtil.java:247)
at org.hibernate.jpa.test.inheritance.singletable.TwoRelationshipsToSubclassTest.test(TwoRelationshipsToSubclassTest.java:64)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.junit.runners.model.FrameworkMethod.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.hibernate.testing.junit4.ExtendedFrameworkMethod.invokeExplosively(ExtendedFrameworkMethod.java:45)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:298)
at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:292)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.lang.Thread.run(Thread.java:832)
org.hibernate.jpa.test.inheritance.singletable.TwoRelationshipsToSubclassTest > test FAILED
java.lang.AssertionError at TwoRelationshipsToSubclassTest.java:68
1 test completed, 1 failed
> Task :hibernate-core:test FAILED
> Task :hibernate-core:buildDashboard UP-TO-DATE
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':hibernate-core:test'.
> There were failing tests. See the report at: file:///C:/projects/hibernate-orm/hibernate-core/target/reports/tests/test/index.html
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
这里发生的是获取所有类型的子类实例（大小 5），这是错误的（应该是 2 个图像和 3 个文档）。
此测试在所有 Hibernate 5.x 分支、5.3、5.4、5.5 和 5.6 中均失败。在 Hibernate 6.0.0.RC1 上，此测试运行良好（如我所料）。
问题（S）：
这是否符合 JPA 规范？这是 Hibernate 5.x 中的错误吗？
有谁知道是哪一期HHH-??????为 Hibernate 修复了这个 6.x?
注意：我们目前必须添加专有 @Where(clause = "DISCR = 'D'") 和 @Where(clause = "DISCR = 'I'") 来解决这个问题。
这是所有 Hibernate 5.x 版本中的错误。
I don’t know which HHH fixed this or if we even tagged a commit properly. We just figured that this was wrong in Hibernate 5.x so we fixed it at some point.
看这里：
我们有一个简单的单一 table 映射，一艘附有图像和文档（均为附件的子 类）的船：
@Entity
@Table(name = "SHIPS")
public class Ship implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "ID")
private Long id;
@Basic(optional = false)
@Column(name = "NAME")
private String name;
@OneToMany(mappedBy = "ship", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
// @Where(clause = "DISCR = 'I'")
private List<Image> images = new ArrayList<>();
@OneToMany(mappedBy = "ship", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
// @Where(clause = "DISCR = 'D'")
private List<Document> documents = new ArrayList<>();
public Ship() {}
public Ship(Long id, String name) {
this.id = id;
this.name = 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;
}
public List<Image> getImages() {
return images;
}
public void setImages(List<Image> images) {
this.images = images;
}
public List<Document> getDocuments() {
return documents;
}
public void setDocuments(List<Document> documents) {
this.documents = documents;
}
}
@Entity
@Table(name = "ATTACHMENTS")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "DISCR")
public abstract class BaseAttachment implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "ID")
protected Long id;
@Basic(optional = false)
@Column(name = "DISCR", insertable = false, updatable = false)
protected String discr;
@Basic(optional = false)
@Column(name = "FILE_NAME")
protected String fileName;
// @Lob
// @Basic(optional = false)
// @Column(name = "ORIGINAL_DATA")
// protected byte[] originalData;
@ManyToOne(optional = false, fetch = FetchType.LAZY)
@JoinColumn(name = "SHIP_ID", referencedColumnName = "ID")
protected Ship ship;
public BaseAttachment() {}
public BaseAttachment(Long id, String fileName) {
this.id = id;
this.fileName = fileName;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getDiscr() {
return discr;
}
public void setDiscr(String discr) {
this.discr = discr;
}
public String getFileName() {
return fileName;
}
public void setFileName(String fileName) {
this.fileName = fileName;
}
// public byte[] getOriginalData() {
// return originalData;
// }
//
// public void setOriginalData(byte[] originalData) {
// this.originalData = originalData;
// }
public Ship getShip() {
return ship;
}
public void setShip(Ship ship) {
this.ship = ship;
}
}
@Entity
@DiscriminatorValue("I")
public class Image extends BaseAttachment {
private static final long serialVersionUID = 1L;
@Column(name = "ALTERNATIVE_TEXT")
private String alternativeText;
public Image() {}
public Image(Long id, String fileName) {
super(id, fileName);
}
public String getAlternativeText() {
return alternativeText;
}
public void setAlternativeText(String alternativeText) {
this.alternativeText = alternativeText;
}
}
@Entity
@DiscriminatorValue("D")
public class Document extends BaseAttachment {
private static final long serialVersionUID = 1L;
public Document() {}
public Document(Long id, String fileName) {
super(id, fileName);
}
}
我为 Hibernate 创建了一个测试用例：
@TestForIssue( jiraKey = "HHH-99999")
public class TwoRelationshipsToSubclassTest extends BaseEntityManagerFunctionalTestCase {
@Override
public Class<?>[] getAnnotatedClasses() {
return new Class<?>[]{Ship.class, BaseAttachment.class, Image.class, Document.class};
}
@Override
protected void addConfigOptions(Map options) {
options.put( AvailableSettings.USE_SECOND_LEVEL_CACHE, "false" );
options.put( AvailableSettings.SHOW_SQL, "true" );
options.put( AvailableSettings.FORMAT_SQL, "true" );
options.put( AvailableSettings.ENABLE_LAZY_LOAD_NO_TRANS, "true" );
}
@Before
public void prepare() {
doInJPA( this::entityManagerFactory, em -> {
Ship ship = new Ship(1L, "Titanic");
// images
Image image1 = new Image(1L, "abc.png");
image1.setShip(ship);
Image image2 = new Image(2L, "def.jpg");
image2.setShip(ship);
// documents
Document document1 = new Document(3L, "ghi.docx");
document1.setShip(ship);
Document document2 = new Document(4L, "jkl.pdf");
document2.setShip(ship);
Document document3 = new Document(5L, "mno.txt");
document3.setShip(ship);
// images relationship
ship.getImages().add(image1);
ship.getImages().add(image2);
// documents relationship
ship.getDocuments().add(document1);
ship.getDocuments().add(document2);
ship.getDocuments().add(document3);
// persist
em.persist( ship );
});
}
/**
* Use --debug to see the SQL being run + the sysouts.
*/
@Test
public void test() {
doInJPA( this::entityManagerFactory, em -> {
Ship ship = em.find( Ship.class, 1L );
Assert.assertNotNull("Ship not found!", ship);
List<Image> images = ship.getImages();
Assert.assertEquals(2, images.size());
List<Document> documents = ship.getDocuments();
Assert.assertEquals(3, documents.size());
} );
}
}
失败：
expected:<2> but was:<5>
Expected :2
Actual :5
<Click to see difference>
java.lang.AssertionError: expected:<2> but was:<5>
at org.junit.Assert.fail(Assert.java:88)
at org.junit.Assert.failNotEquals(Assert.java:834)
at org.junit.Assert.assertEquals(Assert.java:645)
at org.junit.Assert.assertEquals(Assert.java:631)
at org.hibernate.jpa.test.inheritance.singletable.TwoRelationshipsToSubclassTest.lambda$test(TwoRelationshipsToSubclassTest.java:68)
at org.hibernate.testing.transaction.TransactionUtil.doInJPA(TransactionUtil.java:206)
at org.hibernate.testing.transaction.TransactionUtil.doInJPA(TransactionUtil.java:247)
at org.hibernate.jpa.test.inheritance.singletable.TwoRelationshipsToSubclassTest.test(TwoRelationshipsToSubclassTest.java:64)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.junit.runners.model.FrameworkMethod.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.hibernate.testing.junit4.ExtendedFrameworkMethod.invokeExplosively(ExtendedFrameworkMethod.java:45)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:298)
at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:292)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.lang.Thread.run(Thread.java:832)
org.hibernate.jpa.test.inheritance.singletable.TwoRelationshipsToSubclassTest > test FAILED
java.lang.AssertionError at TwoRelationshipsToSubclassTest.java:68
1 test completed, 1 failed
> Task :hibernate-core:test FAILED
> Task :hibernate-core:buildDashboard UP-TO-DATE
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':hibernate-core:test'.
> There were failing tests. See the report at: file:///C:/projects/hibernate-orm/hibernate-core/target/reports/tests/test/index.html
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
这里发生的是获取所有类型的子类实例（大小 5），这是错误的（应该是 2 个图像和 3 个文档）。
此测试在所有 Hibernate 5.x 分支、5.3、5.4、5.5 和 5.6 中均失败。在 Hibernate 6.0.0.RC1 上，此测试运行良好（如我所料）。
问题（S）：
这是否符合 JPA 规范？这是 Hibernate 5.x 中的错误吗？
有谁知道是哪一期HHH-??????为 Hibernate 修复了这个 6.x?
注意：我们目前必须添加专有 @Where(clause = "DISCR = 'D'") 和 @Where(clause = "DISCR = 'I'") 来解决这个问题。
这是所有 Hibernate 5.x 版本中的错误。
I don’t know which HHH fixed this or if we even tagged a commit properly. We just figured that this was wrong in Hibernate 5.x so we fixed it at some point.
看这里：