How to specify the encoding in Spring Data JPA?

data is displayed as ??? instead of Russian letters. Here is the file application.propertie s:

spring.datasource.url: jdbc: firebirdsql: // localhost: 3050 / D: /DB/mybase.gdb spring. masterkey spring.jpa.hibernate.ddl-auto: update spring.jpa.show-sql: true spring.jpa.properties.hibernate.format_sql: true spring.datasource.connectionProperties: useUnicode = true; characterEncoding = UTF-8;