如何使用 H2 数据库获取 DataIntegrityViolationException 上的constraintName？

Question

I'm using PostgreSQL on production and H2 on development.

I handle DataIntegrityViolationException in a SpringBoot ControllerAdvice and I want to get the name of the constraint that drives to this exception.

My table is defined like that :

@Table(name = "user", uniqueConstraints = {
    @UniqueConstraint(name = "users_unique_email_idx", columnNames = {"email"})
})
class User ...

When I use PostgreSQL it works perfectly. I get the cause of exception which is a ConstraintViolationException and then get the constraint name. Something like that :

((ConstraintViolationException)ex.getCause()).getConstraintName()

But using H2 Database I can't find a way to get the constraintName. The DataIntegrityViolationException doesn't contain the ConstraintViolationException or the constraintName. With H2 the error message is empty :

DataIntegrityViolationException:
  could not execute statement; SQL [n/a]; constraint [null];
Caused by:
  JdbcSQLException: Violation dindex unique ou clé primaire: {0}
  Unique index or primary key violation: {0}; SQL statement:

Note : In my H2 INFORMATION_SCHEMA.CONSTRAINTS table my constraint on email field exists and has the good name ( users_unique_email_idx )

Is it a limitation of H2 Database ?
How can I enable constraint name in H2 ?

Thanks !

Answer 1

Answer is Hibernate translate PostgreSQL contraints exception base on database messages.
In class org.hibernate.dialect.PostgreSQL81Dialect we can find a object TemplatedViolatedConstraintNameExtracter that checks if the message from database contains string violates unique constraint . if you changed the language for database, hibernate cannot translate the exception because it is based on English. This is the reason why Hibernate cannot find the constraint name. There are 2 solutions:

1. Change environment variables LC_MESSAGES to English. messages from PostgreSQL will be presented in English.
2. Extend PostgreSQL dialect class (there are few classes depends on PostgreSQL version) and override getViolatedConstraintNameExtracter . Create your own ViolatedConstraintNameExtracter object than will translate your language.

In H2 Database case check according to above.