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Finds Hibernate bugs that fail silently, and shows them as warnings in your code.

In some cases Hibernate doesn't work correctly, but doesn't show any error either. For example, a field may be null when it shouldn't be, or some data may not be saved. Bugs like these are hard to find. This plugin finds some of these cases while you type, and tells you how to fix them.

It adds these inspections, under Settings > Editor > Inspections > Hibernate inspections:

• Persisted class is final: an entity class declared as final. • Final method of a persisted class uses direct field access: a final method that reads or writes a field of an entity. • Embeddable subclasses embeddable: an @Embeddable class that extends another @Embeddable class (only a problem before Hibernate 6.6).

Works with jakarta.persistence (Hibernate 6 and newer) and javax.persistence (Hibernate 5 and older) annotations. Only classes that use annotations are checked, not XML mappings.

Persisted class is final

To load data only when it's needed ("lazy loading"), Hibernate creates a subclass of your entity, called a proxy. It can't create a subclass of a final class, so Hibernate can't load it lazily, which can make your app slower.

How to fix it: remove final from the class (press Alt+Enter on the warning, and choose Remove 'final' modifier). Records are not reported.

Final method of a persisted class uses direct field access

This is almost always a bug, and it fails silently. The proxy that Hibernate creates is a subclass of your class, and its fields are always empty. The proxy can't override a final method, so when you call that method on a proxy, it reads the proxy's empty fields. You get null, 0 or false instead of the real value, and no error.

@Entity public class Cat { private String name; public final String getName() { return name; } // Warning }

How to fix it: remove final from the method (Alt+Enter), or don't use fields directly in final methods. Static methods and static fields are not reported.

A final getId() that reads the id from the proxy is a valid exception. To turn off the warning for one method, add @SuppressWarnings("AccessingFieldFromAFinalMethodOfPersistedClass") to it.

Embeddable subclasses embeddable

Before version 6.6, Hibernate doesn't support an @Embeddable class that extends another @Embeddable class. It saves only some of the fields, and may silently set the embedded object to null when loading. Hibernate 6.6 and newer support it, so if your project uses Hibernate 6.6 or newer, this warning is not shown.

More information

• Full documentation and source code • Report a bug or suggest a new inspection

Created by Marcelo Glasberg: glasberg.dev, GitHub, LinkedIn, Stack Overflow.