Generate SQL from ChangeLog using API and being Offline

1. Database database = DatabaseFactory.getInstance()
2.   .findCorrectDatabaseImplementation(new OfflineConnection("offline:oracle"));
3. Liquibase liquibase = new Liquibase("changeLog.xml", resourceAccessor, database);
4. liquibase.update(new Contexts(), writer);

But I get on the very first line:

1. liquibase.exception.UnexpectedLiquibaseException: java.lang.NoSuchMethodException: liquibase.database.OfflineConnection.getWrappedConnection()
2.     at liquibase.database.core.OracleDatabase.setConnection(OracleDatabase.java:62)
3.     at liquibase.database.DatabaseFactory.findCorrectDatabaseImplementation(DatabaseFactory.java:123)

What I did miss? Where could I find an example of code to do that?

Thanks for your help,

Gérald