lors de
em = JavaPersistenceUtil.getEmf().createEntityManager();

J'ai l'erreur

10:03:31,679 INFO [SettingsFactory] RDBMS: HSQL Database Engine, version: 1.8.0
10:03:31,679 INFO [SettingsFactory] JDBC driver: HSQL Database Engine Driver, version: 1.8.0
10:03:31,679 DEBUG [NewPooledConnection] A Throwable occurred while trying to reset the typeMap property of our Connection to Collections.EMPTY_MAP!
java.sql.SQLException: This function is not supported

D'autre part j'ai vu dans la javadoc de org.hsqldb.jdbc
public void setTypeMap(java.util.Map map)
throws java.sql.SQLException
HSQLDB 1.7.2 does not support this feature. Calling this method always throws a SQLException, stating that the function is not supported.